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What is a DOI? | Finding and Using Digital Object Identifiers

Published on December 19, 2018 by Courtney Gahan . Revised on February 24, 2023 by Raimo Streefkerk.

A DOI (Digital Object Identifier) is a unique and never-changing string assigned to online (journal) articles , books , and other works. DOIs make it easier to retrieve works, which is why citation styles, like APA and MLA Style , recommend including them in citations.

You may find DOIs formatted in various ways:

• doi:10.1080/02626667.2018.1560449
• https://doi.org/10.1111/hex.12487
• https://dx.doi.org/10.1080/02626667.2018.1560449
• https://doi.org/10.1016/j.jpsychires.2017.11.014

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Table of contents

How to find a doi, apa style guidelines for using dois, mla style guidelines for using dois, chicago style guidelines for using dois, frequently asked questions about dois.

The DOI will usually be clearly visible when you open a journal article on a database.

Examples of where to find DOIs

• Taylor and Francis Online
• SAGE journals

Note: JSTOR uses a different format, but their “stable URL” functions in the same way as a DOI.

What to do when you cannot find the DOI

If you cannot find the DOI for a journal article, you can also check Crossref . Simply paste the relevant information into the “Search Metadata” box to find the DOI. If the DOI does not exist here, the article most likely does not have one; in this case, use a URL instead.

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APA Style guidelines state that DOIs should be included whenever they’re available. In practice, almost all journal articles and most academic books have a DOI assigned to them.

You can find the DOI on the first page of the article or copyright page of a book. Omit the DOI from the APA citation if you cannot find it.

Formatting DOIs in APA Style

DOIs are included at the end of the APA reference entry . In the 6th edition of the APA publication manual, DOIs can be preceded by the label “doi:” or formatted as URLs. In the 7th edition , DOIs should be formatted as URLs with ‘https://doi.org/’ preceding the DOI.

• APA 6th edition: doi: 10.1177/0269881118806297 or https://doi.org/ 10.1177/0269881118806297
• APA 7th edition: https://doi.org/ 10.1177/0269881118806297

APA citation examples with DOI

• Fardouly, J., & Vartanian, L. R. (2016). Social media and body image concerns: Current research and future directions. Current Opinion in Psychology , 9 , 1–5. https://doi.org/10.1016/j.copsyc.2015.09.005
• Sustersic, M., Gauchet, A., Foote, A., & Bosson, J.-L. (2016). How best to use and evaluate Patient Information Leaflets given during a consultation: a systematic review of literature reviews. Health Expectations , 20 (4), 531–542. https://doi.org/10.1111/hex.12487

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MLA recommends using the format doi:10.1177/0269881118806297.

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In Chicago style , the format https://doi.org/10.1177/0269881118806297 is preferred.

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A DOI is a unique identifier for a digital document. DOIs are important in academic citation because they are more permanent than URLs, ensuring that your reader can reliably locate the source.

Journal articles and ebooks can often be found on multiple different websites and databases. The URL of the page where an article is hosted can be changed or removed over time, but a DOI is linked to the specific document and never changes.

The DOI is usually clearly visible when you open a journal article on an academic database. It is often listed near the publication date, and includes “doi.org” or “DOI:”. If the database has a “cite this article” button, this should also produce a citation with the DOI included.

If you can’t find the DOI, you can search on Crossref using information like the author, the article title, and the journal name.

Include the DOI at the very end of the APA reference entry . If you’re using the 6th edition APA guidelines, the DOI is preceded by the label “doi:”. In the 7th edition , the DOI is preceded by ‘https://doi.org/’.

• 6th edition: doi: 10.1177/0894439316660340
• 7th edition: https://doi.org/ 10.1177/0894439316660340

APA citation example (7th edition)

Hawi, N. S., & Samaha, M. (2016). The relations among social media addiction, self-esteem, and life satisfaction in university students. Social Science Computer Review , 35 (5), 576–586. https://doi.org/10.1177/0894439316660340

In an APA journal citation , if a DOI (digital object identifier) is available for an article, always include it.

If an article has no DOI, and you accessed it through a database or in print, just omit the DOI.

If an article has no DOI, and you accessed it through a website other than a database (for example, the journal’s own website), include a URL linking to the article.

In MLA style citations , format a DOI as a link, including “https://doi.org/” at the start and then the unique numerical code of the article.

DOIs are used mainly when citing journal articles in MLA .

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Gahan, C. (2023, February 24). What is a DOI? | Finding and Using Digital Object Identifiers. Scribbr. Retrieved July 17, 2024, from https://www.scribbr.com/citing-sources/what-is-a-doi/

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How to find an article's DOI to include in a citation

A DOI (Digital Object Identifier) is a unique identifier that identifies digital objects. The object may change physical locations, but the DOI assigned to that object will never change. Journal publishers often assign DOIs to electronic copies of individual articles in their journals. Because the DOI insures findability for the e-journal article, many citation styles (APA, MLA, Chicago Manual of Style, Turabian, etc.) require the use of a DOI in a citation for e-journal content. Below are some methods that can be used to obtain DOIs:

• Go to http://www.crossref.org/ and follow the instructions provided there to search for a DOI using the article title and author's last name. If this method doesn't yield a DOI, don't assume that a DOI doesn't exist. Follow up with the next two options.  
• If a journal publisher uses DOIs, they will usually print the DOI somewhere on the first page of the article. Open the full-text source and look for the DOI on the article's first page, usually in the header or footer.  
• Some online resources, such as EBSCO databases, will supply DOIs in their citation formatter. View the full citation to see if a DOI is included.

DOI Pro Tip:

• Some articles won't have a DOI. The International DOI Foundation was created in 1998 but not all publishers immediately started assigning DOIs. The publisher Elsevier, for example, appears to have started using DOIs on all of their journal articles around 2003. So unless a publisher has retrospectively assigned DOIs to articles, articles published prior to 1998 are less likely to have DOIs. So, if you have tried all the suggestions above, but you still cannot find the DOI, it may be that your article does not have one.

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DOI Help: Digital Object Identifiers (DOIs)

Introduction.

For APA 7, you need to provide the digital object identifier (DOI) number for articles and ebooks when available. If an item does not have a DOI, the citation will look like the citation for a print resource. You no longer need to locate a journal homepage as part of your citation. 

The goal of this guide is to help you find the DOI for your reference citations. Specifically, this guide will cover:

• what DOIs are
• how to find DOIs

This guide will not cover how to correctly cite articles using APA style. For help with citation questions, please contact the Writing Center or refer to the Writing Center's resources on their website:

• Writing Center: Reference List: Electronic Source References
• Writing Center: Reference List: Common Reference List Examples

What is a Digital Object Identifier (DOI)?

What is a doi.

Digital Object Identifiers, commonly shortened to DOIs, were invented to give each electronic, or digital, item a unique, persistent identifier. Any digital object can be assigned a DOI number, for example:

• academic journal articles 
• research reports 
• governmental reports
• conference proceedings
• media 

Who assigns DOIs?

The DOI creation process is governed and managed by the International DOI Foundation . DOI Registration agencies under the International DOI Foundation provide services and registration of DOI numbers. They are typically focused on specific geographic areas or types of content. For example, EIDR provides DOI numbers for movie and television content.

Crossref is one of the registration agencies for the International DOI Foundation. It assigns DOIs to scholarly research publications. These publications include journal articles, books, and conference proceedings.

What do DOIs look like?

All DOIs start with the number 10 followed by a period. This is an example:

10.1111/dome.12082

In APA 7, you format the DOIs as a URL, with "https://doi.org/" before the number. For example:

https://doi.org/ 10.1111/dome.12082

Things to know

There are a couple of important things to know about DOIs.

• Not every article or resources has a DOI .
• Both peer-reviewed and non-peer-reviewed articles can have DOIs.
• Quick Answer: What is peer review?

Look at the article

The first place to look for a DOI is the article itself. Many publishers will include the DOI somewhere on the first page of the article. Here are a few examples:

Journal of Social Issues, Vol. 71, No. 3, 2015, pp. 441-452 doi: 10.1111/josi.12122

DOI: 10.111/dome.12082 Digest of Middle East Student - Volume 25, Number 1 - Pages 36-51 © 2016 Policy Studies Organization. Published by Wiley Periodicals, Inc.  

Look at information about the article

Library databases include information about an article. If an article has a DOI, you may find it listed in the information about the article.

Different databases call these article information sections different things. They may be called Detailed Record, Abstract, Abstract/Details, or you may need to click on the article title to see more information about the article. 

If you don't see the DOI on the article itself, look around the page in the database to see if the DOI is listed.

Search Crossref

You can look for a DOI using the Crossref website. Crossref is one of the organizations that assigns DOIs, with a focus on research articles. If Crossref doesn't have a DOI for an article, you can safely assume that the article doesn't have one. 

Follow these steps to search Crossref for an article's DOI: 

• Go to the Crossref.org website .

• Press the Enter key to run your search.

Note: The actual DOI begins with 10. For APA 7, include "https://doi.org/" in front of the number. To learn more about what form of the DOI to use in a reference citation, please see these Quick Answers from the Writing Center:

• Quick Answer: Should I include a hyperlink in a DOI?
• Quick Answer: Can I use the DOI format provided by library databases?

Searches in Crossref always bring back results, even if the article you are looking for isn't there. If you don't see your article in the first page of results, here are a few things to try.

• For example:  "Storytelling for social change" AND Winskell
• Use the  Year  limiter in the left column to limit results to only the year in which your item was published.

If you still don't find the article you are looking for in Crossref, you can safely assume that it does not have a DOI.

More information

• DOI, Other URL, or No Retrieval Information? clickable flowchart
• Quick Answer: How do I cite an article with a DOI?
• Quick Answer: How do I cite an article without a DOI?
• Quick Answer: How do I find an article by DOI using Google Scholar?
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How to find a DOI?

Location of DOIs

How to include a doi in your citation, frequently asked questions about finding dois, related articles.

A digital object identifier , or DOI, refers to a handle that recognizes a unique object in the digital world. This label is assigned by the International Organization for Standardization (ISO) to different types of scholarly material, such as papers, journal articles, books, data sets, reports, government publications, and even videos.

A DOI should always be easily available in any source. Usually, you will find it on the first page, either in the header or somewhere close to the title.

Alternatively, you can also find it in the "About this article" or "Cite this article" sections.

If the DOI isn’t available, you can look it up on CrossRef.org by using the “Search Metadata” option. You just have to type in the source's title or author, and it will direct you to its DOI.

The correct format for adding a DOI to your citations will depend on the citation style you use. Here is a list of citation examples with DOIs in major formatting styles:

Hofman, C. A., & Rick, T. C. (2018). Ancient Biological Invasions and Island Ecosystems: Tracking Translocations of Wild Plants and Animals. Journal of Archeological Research , 26 (1), 65–115. https://doi.org/10.1007/s10814-017-9105-3

Hofman, Courtney A., and Torben C. Rick. “Ancient Biological Invasions and Island Ecosystems: Tracking Translocations of Wild Plants and Animals.”  Journal of Archaeological Research , vol. 26, no. 1, 2018, pp. 65–115, doi:10.1007/s10814-017-9105-3.

Hofman, Courtney A., and Torben C. Rick. 2018. “Ancient Biological Invasions and Island Ecosystems: Tracking Translocations of Wild Plants and Animals.”  Journal of Archaeological Research  26 (1): 65–115. https://doi.org/10.1007/s10814-017-9105-3.

The preferred format of a DOI in a citation is using https://doi.org/ followed by the alphanumeric string. It also depends on the style; as you can see that MLA prefers using doi:xxx. Make sure to double-check the citation style you use before adding the DOI.

Tip: Instead of manually adding citations with DOIs to your documents, which is error-prone and strenuous, consider using a reference manager like Paperpile to format and organize your citations. Paperpile allows you to save and organize your citations for later use and cite them in thousands of citation styles directly in Google Docs, Microsoft Word, or LaTeX, including the DOI:

The preferred format of a DOI in a citation is using https://doi.org/ followed by the alphanumeric string. Of course, it depends on the style, as MLA prefers using doi:xxx. Make sure to double check the citation style you use before adding the DOI.

The International Organization for Standardization (ISO) is responsible for assigning DOIs to different types of scholarly material, such as papers, journal articles, books, data sets, reports, government publications, and even videos.

URLs and DOIs are not the same. A DOI is a unique alphanumeric identifier that labels digital material and pinpoints its location on the internet, whereas a URL is a digital locator.

DOIs were invented for a reason. These alphanumeric identifiers allow readers to locate specific material in the digital world. They also add credibility to your sources.

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What is a DOI (digital object identifier)?

A DOI is a character string that can be assigned to an online article, book, or other source. If the location of the source changes, the DOI remains stable, which allows readers to locate the source. When you use the APA citation style, you should always include the DOI if one has been assigned to the source you are citing.

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Digital Object Identifiers Digital Object Identifiers

A Digital Object Identifier (DOI) is a number used to identify an electronic journal article or other online intellectual property. Because DOIs remain stable even if an article’s host publication changes platforms, names, or publishers, they provide permanent and reliable links for citation, sharing, and discovery. When properly implemented in citations and references, DOIs can provide readers and researchers instant access to the sources they’re looking for.

DOIs are designated and administered by the  CrossRef  organization, which is operated by the independent, nonprofit Publishers International Linking Association (PILA). Since their first implementation in 1999, DOIs have quickly become the backbone of CrossRef’s mandate to provide a “digital switchboard” that links all scholarly information in electronic form. Implementing DOIs for your journals and other online publications is an effective and respected way to increase access and exposure.

Citing with DOIs

In order for the digital switchboard to work, DOIs in URL format need to be included in citations and references. In fact, CrossRef requires journals that use DOIs for their own articles to include DOIs in their footnotes and bibliographies. This requirement applies only to content published after the publisher or journal has joined CrossRef. Below are common examples.

Chicago Manual of Style:

Kossinets, Gueorgi, and Duncan J. Watts. “Origins of Homophily in an Evolving Social Network.”  American Journal of Sociology  115 (2009): 405–50. Accessed February 28, 2010. https://doi.org/10.1086/599247.

Wooldridge, M.B., & Shapka, J. (2012). Playing with technology: Mother-toddler interaction scores lower during play with electronic toys.  Journal of Applied Developmental Psychology, 33 (5), 211-218. https://doi.org/10.1016/j.appdev.2012.05.005

Note that the full URL, not simply the digits of the DOI, should be included in the reference. Most style guides now recommend inclusion of DOIs in citations wherever they’re available, and authors should be instructed to follow this recommendation. If your journal is a member of CrossRef, then by extension, authors are members as well. Ultimately, however, it is the editors’ responsibility to ensure that DOIs are included in references and citations to any article that has a DOI. Fortunately, CrossRef provides strong tools to help authors and editors to meet these requirements.

Adding DOIs to Journals in Digital Commons

If a Digital Commons journal would like to include DOIs with its content, please ask your consultant about the latest options.

CrossRef offers a wealth of information and technical resources on DOIs. We particularly recommend the following:

• See the CrossRef DOI Display Guidelines ( https://www.crossref.org/display-guidelines/ ) for more details, examples, and instructions on displaying your own content’s DOIs and citing DOIs in your footnotes and references
• The Simple Text Query Form retrieves DOIs for single bibliographic entries or a complete reference list:  https://doi.crossref.org/simpleTextQuery

Resource for transforming Digital Commons XML to Crossref XML:

• Mortimore, Jeffrey M., “XSL File for Transformation of bepress Digital Commons Issue-Level Journal XML to Crossref 4.4.2 XML” (2020).  Faculty Datasets . 7.  https://digitalcommons.georgiasouthern.edu/data/7 )

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What is a DOI and how do I use them in citations?

A DOI, or Digital Object Identifier, is a string of numbers, letters and symbols used to uniquely identify an article or document, and to provide it with a permanent web address (URL).

A DOI will help your reader easily locate a document from your citation. Think of it like a Social Security number for the article you're citing — it will always refer to that article, and only that one. While a web address (URL) might change, the DOI will never change.

Where can I find a DOI?

• In most scholarly journal articles, the DOI will be printed with the article itself, usually on the first page somewhere: below the title or in the header or footer.
• If the DOI isn't included in the article, look it up on the website  CrossRef.org  (use the "Search Metadata" option) to check for an assigned DOI.

How can I use a DOI to find the article it refers to?

• If your DOI starts with http:// or https:// , simply paste it into your web browser. This will usually lead you to a journal publisher's page for the article.
• You can turn any DOI starting with 10 into a URL by adding http://doi.org/ before the DOI. For example, 10.3352/jeehp.2013.10.3 becomes  https://doi.org/10.3352/jeehp.2013.10.3
• If you're off campus when you do this, you'll need to use this URL prefix in front of the DOI to gain access to UIC's full text journal subscriptions: https://proxy.cc.uic.edu/login?url=https://doi.org/ . For example:  https://proxy.cc.uic.edu/login?url=http://doi.org/10.3352/jeehp.2013.10.3

Psst! It's not a bad i dea to check the DOIs in your references list this way to make sure they lead to the correct articles!

How do I cite a journal article with a DOI in...

Apa format.

• Author, A. A., & Author, B. B. (Date of publication). Title of article. Title of Journal, volume number, page range. https://doi.org/10.0000/0000
• Author, A. A., & Author, B. B. (Date of publication). Title of article. Title of Journal, volume number, page range.
• If your article includes both a DOI and a URL, include only the DOI.
• See these and other examples in the Purdue OWL: APA Formatting and Style Guide .

AMA/JAMA format?

• 1. Author AA, Author BB. Title of article. Name of Jrnl. Year;vol(issue):inclusive pages. doi:10.0000000/000000000000

MLA format?

• Author LastName, FirstName, and FirstName LastName. "Article Title." Journal Name , vol. #, no. #, date, pp. ##-##. Name of Database , doi: 10.0000/000000000.
• It's a good idea to check with your instructor whether they want you to include the date you accessed the article, although this is not required by MLA.
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• created: May 27, 2021
• updated: Aug 19, 2021
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ISBN, ISSN, DOI: what they are and how to find them

Isbn-issn-doi-what-they-are-and-how-to-find-them.

June 17, 2022

Discover some of the unique content identifiers that are used for published content at Wiley including ISBN, ISSN, and DOI. For articles or chapters, DOI is our preferred identifier when available.

• ISBN stands for International Standard Book Number and is used for books.
• ISBNs may be 10 or 13 digits.
• On a physical book, you may find the ISBN next to the barcode. You will also find it on the copyright page. In an ebook, the ISBN is available in the copyright information. ISBNs can also be found in our  book product catalog on Wiley.com .
• Print and digital formats carry different ISBNs. ISBNs are a standard defined by the International Standards Organization and are issued through national agencies. 
• ISSN stands for International Standard Serial Number and is used for journals, magazines, and other serial publications.
• It is made up of two sets of four digits with a dash between them (0000-0000).
• You can find the ISSN in the copyright information of a print journal, or on the journal homepage of a digital journal. Print and digital formats carry different ISSNs.
• Globally, ISSNs are managed by the intergovernmental organization the ISSN International Centre.  
• DOI stands for Digital Object Identifier . It is a unique identifier for digital content, used across the industry and managed by the not-for-profit organization CrossRef .
• Both book and journal content use DOI. Unlike ISBN and ISSN, which identify content at the book or journal level, a DOI may identify an individual chapter or article.
• A DOI may be formatted as a URL string, or it may be a standalone cataloging number. On Wiley Online Library, a DOI may be found at the top of an article or chapter record, beneath the byline.

If you have a question about a specific piece of Wiley content, you may be asked to provide a unique content identifier to help our team locate the content in our records. We hope this guide enables you to do so quickly and efficiently. 

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What is a digital object identifier, or DOI?

Go to 7th edition guidelines

A digital object identifier (DOI) is a unique alphanumeric string assigned by a registration agency (the International DOI Foundation) to identify content and provide a persistent link to its location on the internet. The publisher assigns a DOI when your article is published and made available electronically.

All DOI numbers begin with a 10 and contain a prefix and a suffix separated by a slash. The prefix is a unique number of four or more digits assigned to organizations; the suffix is assigned by the publisher and was designed to be flexible with publisher identification standards.

We recommend that when DOIs are available, you include them for both print and electronic sources. The DOI is typically located on the first page of the electronic journal article, near the copyright notice. The DOI can also be found on the database landing page for the article.

For more on DOIs, see the DOI category of the APA Style Blog .

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DOI (Digital Object Identifiers)

Search by doi, what's a doi, related resources.

Type or paste an article's DOI into this search box. Our linking system will find which library databases have the article in full-text, and link to Interlibrary Loan if full-text is unavailable.

"DOI" stands for Digital Object Identifier .  It identifies an article, book, or other resource with a permanent and unique combination of numbers and letters.

Example: 10.3928/00220124-20191115-03

Read more at DOI.org

• CrossRef DOI Lookup Need a DOI for a reference list? Find a DOI when you know other citation information
• Citation Resources Guide Citation formats and tools
• Last Updated: Aug 8, 2022 4:13 PM
• URL: https://libguides.sjf.edu/doi

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CrossRef – the DOI search tool

Looking for the DOIs (Digital Object Identifiers) for your citations?  Crossref offers a DOI search for journal articles, books, and chapters.  Simply cut and paste the reference list into their search box.  The form will take any reference style, although it works most reliably with standard styles.

DOIs are used to provide a stable source for information about a digital object, including where they  can be found on the Internet. Information about a digital object may change over time, including where to find it, but its DOI name does not change.

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How can I get the DOI of a paper from its title?

Is there a way to get the DOI (Document Object Identifier) of a research paper when its title is available?

I am preparing a reference database I could not get the URL of all the references. So, I tried to search online but could not get to anything. I will appreciate if anyone uses such tool/website or has any idea.

EDIT I am sorry but my problem is little bigger. I need to automatically (not manually) get them from the websites. Of course, I do not want to do it for more than 50 papers if that is legal/allowed.

• reference-managers

• solutions can be found on stackoverflow and scicomp.SE . And its fit on this site has been addressed on meta.academia.se –  David LeBauer Commented Aug 2, 2012 at 15:51
• 3 By the way, unfortunately you should expect that no technique will be completely reliable, which is why we need DOIs in the first place. –  Anonymous Mathematician Commented Oct 28, 2012 at 14:27

8 Answers 8

Reposted from StackOverflow :

Here are three options CSV upload to crossref.org CrossRef allows you to upload the linked csv directly, and then performs a text query here: http://www.crossref.org/stqUpload/ However, only 18 of the 250 queries (~7%) returned a doi. XML Query Based on the answer on SO by Brian Diggs , here an attempt that does 95% of the work - toward writing the xml-based query, it still has a few bugs that require some deletion using sed . But the biggest problem that my "session timed out" when the query was submitted. the xml syntax includes an option to use fuzzy matching. the doiquery.xml contains the template text in @Brians answer; the citations.csv is linked above. (using R, a sample csv can be found on I have posted the first few lines of the table on google docs , or the csv version (not all records have a doi)) library(XML) doiquery.xml <- xmlTreeParse('doiquery.xml') query <- doiquery.xml$doc$children$query_batch[["body"]] citations <- read.csv("citations.csv") new.query <- function(citation, query = query){ xmlValue(query[["author"]]) <- as.character(citation$author) xmlValue(query[["year"]]) <- as.character(citation$year) xmlValue(query[["article_title"]][["text"]]) <- citation$title xmlValue(query[["journal_title"]]) <- citation$journal return(query) } for (i in 1:nrow(citations)){ q <- addChildren(q, add.query(citations[i,])) } axml <- addChildren(doiquery.xml$doc$children$query_batch, q ) saveXML(axml, file = 'foo.xml') CSV to XML Converter Creativyst software provides a web based CSV to XML converter. Steps: Enter columnames in ElementID's field, "document" in DocID field "query" in RowID field Copy / paste csv in "Input CSV file". Click Convert Also, see this related question: https://stackoverflow.com/questions/9880808/shell-script-to-parse-csv-to-an-xml-query

• 1 This crossref page allows to directly input text query instead of uploading filey. To check for only a few papers, this is convenient. –  Cyriac Antony Commented Sep 20, 2021 at 6:54

So you can do this easily using e.g. Web of Science, and probably other bibliographic databases available through your library.

If that isn't an option, a little google search lead me to the DOI website FAQ , and question 3 is yours. There are 8 registration agencies for DOI, and no single way to search across DOI using document metadata. I tested the free crossref service and it was unable to find one of my articles because that journal doesn't use the crossref agency. One of the other agencies has that information, but you might have to search all of them to find it.

Finally, I tried Google Scholar, which will work if the article in question has reference information available online. That depends on the publisher.

• I also had the same problem with crossref that I tried before posting this question –  Stat-R Commented Jun 26, 2012 at 16:37
• I think Papers or Mendeley mentioned by @aeismail are the way to go - they claim to collect metadata automatically. –  atiretoo Commented Jun 26, 2012 at 16:40

The R package fulltext allows you to search DOI's given a title:

[1] "10.1371/journal.pone.0081457" "10.1371/journal.pone.0030492" "10.1371/journal.pone.0049220"

Resources like Web of Knowledge should have information on the DOI's for any titles that have them available (which should be "all of them" for anything that's been published in the last few years).

Tools like Papers or Mendeley should also be able to "harvest" DOI's for published papers.

• In response to your edit: both Papers and Mendeley should be able to retrieve the metadata for you using the title, unless the paper has just been released (as it might take a while to be archived by various search engines). –  aeismail Commented Jun 26, 2012 at 20:56
• 1 I tried but with no success. I will be grateful if you or someone can tell me a website where we can also fetch/download the link to the documents/references. I will do my search again and not use the existing reference file –  Stat-R Commented Jun 26, 2012 at 21:37

Easier, code-free:

At this time, on the CrossRef homepage , there is a text-input field "Metadata search". It says:

Search CrossRef's database of 71 million records for authors, titles, DOIs, ORCIDs, ISSNs, FundRefs, license URIs, etc. You can even paste entire references into the search box and discover their DOIs.

I have tried it out only for one DOI of which I happen to know that a record exists in the crossref database.

You can also use the CrossRef search site and paste the title of the paper there.

Update in 2022: Easiest for me was using the website, where you can just copy and paste your references: https://search.crossref.org/references

I also looked at a few python libraries to interact with the crossref REST API, e.g.,

https://pypi.org/project/habanero/

https://gitlab.com/crossref/crossref_commons_py

The libraries were easy to use in general, but it was not straight forward how to get the DOI based on a title and there were not really any good examples for this task.

As J. Schneider mentions , you can use "works" field query from crossref api. ( take a look at Richard Feynman example ). It returns a JSON file. You can extract DOI from it.

• As it’s currently written, your answer is unclear. Please edit to add additional details that will help others understand how this addresses the question asked. You can find more information on how to write good answers in the help center . –  Community Bot Commented Jul 5, 2022 at 13:57

As the author of pysotsog I am recommending that library. It searches wikidata at this time and will use other bibliographic databases such as crossref, dblp, library catalogs and so on in the future it's intended to use general search engines as well. The concept is to be a specific search engine for scientific content see sotsog search strategy .

Here is a command line example for the title "We Need a Magna Carta for the Internet" by Tim Berners-Lee with the DOI doi=10.1111/NPQU.11475.

In simple cases like the one above you can directly search wikidata and use the wikibase-cli command line tools for it by searching for the DOI property.

First step - find the paper wikidata entry with a full text search

Query the DOI

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What are DOIs and PMIDs

Find an article using doi or pmid.

DOI stands for Document Object Identifier . This is a unique identifier that is assigned to an online journal article, online book or online book chapter. Most publishers assign these to their online content. A DOI can take you directly to an online resource, but the Library does not always have access at a publisher site. The DOI lookup links to any online access we have.

PMID is a unique identifier used in the PubMed database and can be used to look up abstracts in PubMed. The PMID lookup links to online access through the Library.

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DOI citation generator

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What is a DOI citation generator and how can it help you?

Getting citations and reference lists correctly done can be very confusing and time-consuming.

The good news is that our DOI citation generator can do it automatically for you and it is FREE to use! 🎉

Not convinced yet? Here are 5 reasons why you are going to love the BibGuru DOI citation maker :

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With BibGuru we have made a citation tool that truly helps students to focus on the content of their work instead of worrying about how to get their reference list correctly done.

Those days of wasting time entering data manually or losing grades on incorrect bibliographies are finally gone!

If you need to know more about DOI citations check out our How do I cite in DOI style? section.

Why, when, and what do I have to cite?

Why The broad scientific knowledge we have today is the accomplishment of many researchers over time. To put your own contribution in context , it is important to cite the work of the researchers who influenced you. Cited sources can provide key background information, support or dispute your thesis, or offer important definitions and data. Citing also shows that you have personally read the work.

When In addition to crediting the ideas of others that you used to build your own argument, you need to provide documentation for all facts and figures that are not common knowledge. Common knowledge is knowledge that is known by everyone, or nearly everyone, and can basically concern any subject. An example for common knowledge would be "There are seven days in a week".

What The number of sources you cite in your work depends on the intent of the paper. In most cases, you will need to cite one or two of the most representative sources for each key point. However, if you are working on a review article, the aim is to present to the readers everything that has been written on a topic, so you will need to include a more exhaustive list of citations.

How do I cite with a DOI?

How you cite with a DOI depends on the citation style you use. APA, MLA and all big citation styles include a DOI. BibGuru makes citing with a DOI as easy as it gets. Simply copy and paste the DOI into the Article search field and BibGuru will find your source and give you the correct citation with your DOI in the style you prefer.

DOI stands for digital object identifier and is a string of numbers, letters and symbols used to uniquely identify an article and document and link it to the web. A DOI of an object will never change, which makes it a permanent identification.

How you cite a DOI depends on the citation style you use. Many citation styles, including APA or MLA ask you to include the DOI at the end of your citation in the bibliography. You don't need to worry how to cite a DOI with the BibGuru DOI citation generator in any style - we will do it in the correct way for you.

If you cite in the APA style, include the DOI for all works that have one. If you find an article on the "open web" (such as finding it on Google), and it doesn't have a DOI, you need the full URL of the article.

DOI and ISBN (International Standard Book Number) are two different identification numbers and are totally unrelated.

A DOI is used to permanently identify an electronic article or book and link it to the web. Beware that not all electronic materials will have a DOI. As it is a fairly new concept, books and articles published prior to 2000 are less likely to have a DOI.

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GI indicates gastrointestinal.

Whiskers indicate 95% CIs. GI indicates gastrointestinal.

eTable 1. Categorization of Cancers Within SEER*Stat (Version 8.4.0.1)

eTable 2. Baseline Characteristics of Early-Onset Cancers From 2010 to 2019 a

eTable 3. Incidence of Early-Onset Gastrointestinal Cancers From 2010 and 2019

eTable 4A. Incidence of Early-Onset Gastrointestinal Cancer From 2010 and 2019, Stratified by Sex

eTable 4B. Incidence of Early-Onset Gastrointestinal Cancer From 2010 and 2019, Stratified by Age Group

eTable 4C. Incidence of Early-Onset Gastrointestinal Cancer From 2010 and 2019, Stratified by Race

eTable 5. Incidence of Early-Onset Obesity-Related Cancer From 2010 and 2019

eFigure 1. Incident Early-Onset Cancers From 2010 and 2019

eFigure 2. Age-Standardized Incidence Rate of Early-Onset Cancers From 2010 to 2019, by Race and Ethnicity, Sex, and Age Group

eFigure 3. Annual Percentage Change of Cancers From 2010 to 2019, by Organ System

eFigure 4. Annual Percentage Change of Gastrointestinal Cancers From 2010 to 2019

eFigure 5. Annual Percentage Change of Obesity-Related Cancers, by Age Group

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Koh B , Tan DJH , Ng CH, et al. Patterns in Cancer Incidence Among People Younger Than 50 Years in the US, 2010 to 2019. JAMA Netw Open. 2023;6(8):e2328171. doi:10.1001/jamanetworkopen.2023.28171

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Patterns in Cancer Incidence Among People Younger Than 50 Years in the US, 2010 to 2019

• 1 Yong Loo Lin School of Medicine, National University of Singapore, Singapore
• 2 Division of Gastroenterology and Hepatology, Department of Medicine, National University Hospital, Singapore
• 3 National University Centre for Organ Transplantation, National University Health System, Singapore
• 4 Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, University Surgical Cluster, National University Hospital, Singapore
• 5 Cancer Science Institute of Singapore, National University of Singapore, Singapore
• 6 Department of Medicine, Division of Gastroenterology and Hepatology, University of Arizona College of Medicine, Phoenix
• 7 AW Morrow Gastroenterology and Liver Centre, Royal Prince Alfred Hospital, Sydney, Australia
• 8 Ark Surgical Practice, Mount Elizabeth Hospital, Singapore, Singapore
• 9 Division of Cancer Control and Population Sciences, UPMC Hillman Cancer Center, Pittsburgh, Pennsylvania
• 10 Department of Epidemiology, School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania
• 11 Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, Germany
• 12 Division of Gastroenterology, University of California at San Diego, La Jolla

Question   What are the patterns in the incidence of cancers in people younger than 50 years (ie, early-onset cancers)?

Findings   In this cohort study of 562 145 people with early-onset cancer in the US from 2010 to 2019, the incidence rates of early-onset cancers increased substantially over the study period. Gastrointestinal cancers had the fastest-growing incidence rates among all early-onset cancers.

Meaning   These data may be useful for the development of surveillance strategies and funding priorities.

Importance   Emerging data suggest that the incidence of early-onset cancers, defined as cancers diagnosed in people younger than 50 years, is increasing, but updated data are limited.

Objective   To characterize the patterns in the incidence of early-onset cancers in the US from 2010 to 2019 and provide granular data on the cancers with the fastest-growing incidence rates.

Design, Setting, and Participants   This population-based cohort study analyzed data from 17 National Cancer Institute Surveillance, Epidemiology, and End Results registries from January 1, 2010, to December 31, 2019. Age-standardized incidence rates per 100 000 people were extracted for early-onset cancers, with rates age adjusted to the US standard population. A total of 562 145 patients with early-onset cancer between 2010 and 2019 were identified and included. Data were analyzed from October 16, 2022, to May 23, 2023.

Main Outcomes and Measures   Primary outcomes were incidence rates and descriptive epidemiological data for people younger than 50 years with cancer. The annual percentage change (APC) of the age-standardized incidence rate was estimated using the Joinpoint regression program.

Results   Among 562 145 patients (324 138 [57.7%] aged 40-49 years; 351 120 [62.5%] female) with early-onset cancer, 4565 (0.8%) were American Indian or Alaska Native, 54 876 (9.8%) were Asian or Pacific Islander, 61 048 (10.9%) were Black, 118 099 (21.0%) were Hispanic, 314 610 (56.0%) were White, and 8947 (1.6%) were of unknown race and/or ethnicity. From 2010 to 2019, the age-standardized incidence rate of early-onset cancers increased overall (APC, 0.28%; 95% CI, 0.09%-0.47%; P  = .01) and in female individuals (APC, 0.67%; 95% CI, 0.39%-0.94%; P  = .001) but decreased in male individuals (APC, −0.37%; 95% CI, −0.51% to −0.22%; P  < .001). In contrast, the age-standardized incidence rate of cancers in individuals aged 50 years and older decreased over the study period (APC, −0.87%; 95% CI, −1.06% to −0.67%; P  < .001). In 2019, the highest number of incident cases of early-onset cancer were in the breast (n = 12 649). From 2010 to 2019, gastrointestinal cancers had the fastest-growing incidence rates among all early-onset cancer groups (APC, 2.16%; 95% CI, 1.66%-2.67%; P  < .001). Among gastrointestinal cancers, those with the fastest-growing incidence rates were in the appendix (APC, 15.61%; 95% CI, 9.21%-22.38%; P  < .001), intrahepatic bile duct (APC, 8.12%; 95% CI, 4.94%-11.39%; P  < .001), and pancreas (APC, 2.53%; 95% CI, 1.69%-3.38%; P  < .001).

Conclusions and Relevance   In this cohort study, the incidence rates of early-onset cancer increased from 2010 to 2019. Although breast cancer had the highest number of incident cases, gastrointestinal cancers had the fastest-growing incidence rates among all early-onset cancers. These data may be useful for the development of surveillance strategies and funding priorities.

Cancer has traditionally been considered a disease of older individuals (defined as adults 50 years and older), 1 but recent data suggest a marked increase in the incidence of cancer of various organs among patients younger than 50 years, collectively known as early-onset cancer. 2 , 3 These cancers affect a variety of organ systems, including the breast, colon and/or rectum, pancreas, head and neck, kidney, and reproductive organs. 2 , 4 - 8 The increase in early-onset cancers is likely associated with the increasing incidence of obesity as well as changes in environmental exposures, such as smoke and gasoline, 9 sleep patterns, physical activity, microbiota, and transient exposure to carcinogenic compounds. 10 - 14

Early-onset cancer is associated with substantial mortality and morbidity. 10 , 15 - 18 Recent efforts have evaluated the incidence patterns of specific types of early-onset cancers. 19 - 23 However, an updated comprehensive overview of recent patterns of early-onset cancer in the US that is not limited to specific organ systems has not been reported. 24 This study used population-based data from the National Cancer Institute Surveillance, Epidemiology, and End Results (SEER) program to characterize temporal patterns in the incidence of early-onset cancers in the US from 2010 to 2019. The primary objective was to characterize the temporal patterns in early-onset cancer overall and by organ system. The secondary objective was to assess temporal patterns in early-onset cancer stratified by sex, age group, and race and ethnicity.

This cohort study was conducted in accordance with the Declaration of Helsinki. 25 The study was exempt from institutional review board review because no confidential patient information was involved per the 2018 Revised Common Rule (45 CFR §46). 26 This study followed the Strengthening the Reporting of Observational Studies in Epidemiology ( STROBE ) reporting guideline for cohort studies.

The National Cancer Institute SEER program collects population-based data on cancer incidence in the US. The SEER database is a network of tumor registries from various geographically distinct regions within the country and contains representative data for the racial and ethnic diversity present within the US. 27 The data in the SEER registry are sourced annually from the US Census Bureau, and the registry is estimated to cover approximately 26.5% of the population in the US. 28 In this study, data from 17 SEER registries (hereinafter, SEER 17 database) were used to estimate the number of incident cancer cases from January 1, 2010, to December 31, 2019, as well as the cross-sectional incidence rates and the 10-year mean annual percentage change (APC) in incidence rates. Race and ethnicity categories were determined per the SEER coding manual, which was predominantly based on self-reported data. Data were analyzed from October 16, 2022, to May 23, 2023.

Demographic data were obtained using SEER*Stat software, version 8.4.0.1 (National Cancer Institute), 29 from incident cases of cancer diagnosed between 2010 and 2019 and collected from the SEER 17 database. Population data were segregated based on age, race and ethnicity, and sex available within SEER*Stat. Incidence rates were calculated using SEER*Stat and were age standardized to the 2000 US standard population. 30 Tiwari et al 31 modification was applied for more efficient calculation of CIs for rates and rate ratios. All cases of cancer were classified according to the World Health Organization 2008 definitions, which were based on the International Classification of Diseases for Oncology , third edition. 32 Cancers were grouped according to organ systems (eTable 1 in Supplement 1 ). The APC of incidence rates was quantified using the Joinpoint regression program, version 5.0.2 (National Cancer Institute). 33 Temporal patterns from 2010 to 2019 were evaluated to identify changes that may have occurred over the study period. Rates and APCs across the strata of sex (male or female), race and ethnicity (Hispanic, non-Hispanic American Indian or Alaska Native, non-Hispanic Asian or Pacific Islander, non-Hispanic Black, non-Hispanic White, or unknown race and/or ethnicity), and age group (0-19 years, 20-29 years, 30-39 years, or 40-49 years) were evaluated to identify populations at risk of developing cancer. Analysis of American Indian or Alaska Native populations was restricted to areas with health care services provided by the Indian Health Services for improved accuracy of racial classification. 34 As a result, 960 persons from outside of purchased or referred care delivery areas were excluded from the analysis. The Monte Carlo permutation method was used to test for significance, 33 and 2-sided P  < .05 was considered statistically significant.

Between 2010 and 2019, a total of 562 145 patients with early-onset cancer (324 138 [57.7%] aged 40-49 years; 351 120 [62.5%] female and 211 025 [37.5%] male) were identified over 2 102 085 738 person-years of observation. A total of 4565 patients (0.8%) were American Indian or Alaska Native, 54 876 (9.8%) were Asian or Pacific Islander, 61 048 (10.9%) were Black, 118 099 (21.0%) were Hispanic, 314 610 (56.0%) were White, and 8947 (1.6%) were of unknown race and/or ethnicity (eTable 2 in Supplement 1 ).

The number of incident early-onset cancers was 56 051 in 2010 and 56 468 in 2019, representing an increase of 0.74% during the study period. The number of incident early-onset cancers in male individuals was 21 818 in 2010 and 20 747 in 2019, representing a decrease of 4.91%; the number of incident early-onset cancers in female individuals was 34 233 in 2010 and 35 721 in 2019, representing an increase of 4.35% ( Figure 1 A). By race and ethnicity, the number of incident early-onset cancers in 2010 was 351 among American Indian or Alaska Native people, 4723 among Asian or Pacific Islander people, 6245 among Black people, 10 326 among Hispanic people, and 33 578 among White people; the number of incident early-onset cancers in 2019 was 359 among American Indian or Alaska Native people, 6246 among Asian or Pacific Islander people, 5953 among Black people, 13 177 among Hispanic people, and 29 481 among White people ( Figure 1 B). These values represented an increase of 2.28% among American Indian or Alaska Native people, 32.25% among Asian or Pacific Islander people, and 27.61% among Hispanic people but a decrease of 4.68% among Black people and 12.20% among White people. When stratified by specific age groups, the number of incident early-onset cancers in 2019 was 3983 among individuals aged 0 to 19 years, 5899 among individuals aged 20 to 29 years, 14 762 among individuals aged 30 to 39 years, and 31 824 among individuals aged 40 to 49 years.

The incidence rate of early-onset cancer was 99.96 cases per 100 000 individuals in 2010 and 102.97 cases per 100 000 individuals in 2019. The overall incidence of early-onset cancer increased (APC, 0.28%; 95% CI, 0.09%-0.47%; P  = .01) ( Figure 2 A; Table 1 ). In contrast, the incidence of cancer among individuals 50 years and older decreased over the same period (APC, −0.87%; 95% CI, −1.06% to −0.67%; P  < .001). During the study period, the age-standardized incidence rates of early-onset cancer increased in female individuals (APC, 0.67%; 95% CI, 0.39%-0.94%; P  = .001) but decreased in male individuals (APC, −0.37%; 95% CI, −0.51% to −0.22%; P  < .001) (eFigure 2 in Supplement 1 ). The mean APCs increased in American Indian or Alaska Native people (1.97%; 95% CI, 0.69%-3.27%; P  < .001), Asian or Pacific Islander people (0.97%; 95% CI, 0.58%-1.35%; P  = .007), and Hispanic people (1.43%; 95% CI, 1.05%-1.81%; P  < .001); were stable in White people (0.04%; 95% CI, −0.24% to 0.31%; P  = .77); and decreased in Black people (−0.47%; 95% CI, −0.77% to −0.17%; P  = .007). By age group, the incidence of early-onset cancers increased in individuals aged 30-39 years (APC, 0.91%; 95% CI, 0.44%-1.39%; P  = .002) but remained stable in other age groups. The incident rates among populations 50 years and older decreased, with mean APCs of −0.48% (95% CI, −0.69% to −0.26%; P  = .001) among those aged 50 to 59 years, −0.75% (95% CI, −1.15% to −0.35%; P  = .003) among those aged 60 to 69 years, −1.01% (95% CI, −1.28% to −0.74%; P  < .001) among those aged 70 to 79 years, and −1.16% (95% CI, −1.29% to −1.03%; P  < .001) among those 80 years and older ( Figure 2 B).

The incidence rates and APCs of the individual cancers are summarized in Table 2 . In 2019, the individual cancers with the highest number of incident early-onset cases were cancers of the breast (n = 12 649), thyroid (n = 5869), and colon and/or rectum (n = 4097). From 2010 to 2019, the cancers with the greatest increase in incident cases were in the appendix (251.89%), intrahepatic bile duct (142.22%), and uterus (76.47%). During the study period, the greatest increase in incidence rates occurred in cancers of the appendix (APC, 15.61%; 95% CI, 9.21%-22.38%; P  < .001), intrahepatic bile duct (APC, 8.12%; 95% CI, 4.94%-11.39%; P  < .001), and other digestive organs (APC, 6.63%; 95% CI, 1.58%-11.93%; P  = .02). The greatest decrease in incidence rates of individual early-onset cancers occurred for cancer in the floor of the mouth (APC, −7.58%; 95% CI, −9.59% to −5.52%; P  < .001), acute monocytic leukemia (APC, −6.51%; 95% CI, −8.86% to −4.11%; P  < .001), and prostate cancer (APC, −6.12%; 95% CI, −8.16% to −4.04%; P  < .001).

The number of incident cases of early-onset cancer in 2010 and 2019 by organ system is shown in Figure 1 C and Table 3 . In 2019, the highest number of incident cases of early-onset cancer were in cancers of the breast (n = 12 649), gastrointestinal system (n = 7383), and hematological system (n = 6960). From 2010 to 2019, the greatest increases in the number of incident cases of early-onset cancer occurred in the gastrointestinal system (14.80%; from 6431 cases to 7383 cases), breast (7.70%; from 11 745 cases to 12 649 cases), and endocrine system (8.69%; from 5659 cases to 6151 cases). The mean APCs of early-onset cancer from 2010 to 2019 by organ system are shown in Figure 2 C and Table 3 . From 2010 to 2019, the greatest increases in incidence rates of early-onset cancers occurred in cancers of the gastrointestinal system (APC, 2.16%; 95% CI, 1.66%-2.67%; P  < .001), urinary system (APC, 1.34%; 95% CI, 0.61%-2.07%; P  = .003), and female reproductive system (APC, 0.93%; 95% CI, 0.32%-1.55%; P  = .008) (eFigure 3 in Supplement 1 ). In contrast, the greatest decreases in incidence rates of early-onset cancers occurred in cancers of the respiratory system (APC, −4.57%; 95% CI, −5.30% to −3.83%; P  < .001), male reproductive system (APC, −1.75%; 95% CI, −2.40% to −1.10%; P  < .001), and brain and nervous system (APC, −0.99%; 95% CI, −1.67% to −0.32%; P  = .01).

Because gastrointestinal cancers had the fastest-growing incidence rates among the organ systems, we further explored the incidence patterns among individual gastrointestinal cancers to identify the specific organs contributing to this pattern. The number of incident cases of early-onset gastrointestinal cancers in 2010 and 2019, by individual organ sites, are shown in eFigure 1 in Supplement 1 , and the incidence rates and patterns of early-onset gastrointestinal cancers are shown in eTable 3 in Supplement 1 . In 2019, the highest number of incident cases of early-onset gastrointestinal cancers occurred in the colon and/or rectum (n = 4097), stomach (n = 773), and pancreas (n = 701). From 2010 to 2019, the greatest increases in the number of incident cases of early-onset cancer were in the appendix (251.89%; from 185 cases to 651 cases), intrahepatic bile duct (142.22%; from 45 cases to 109 cases), and pancreas (18.21%; from 593 cases to 701 cases). The greatest increase in the incidence rates of early-onset gastrointestinal cancers was in the appendix (APC, 15.61%; 95% CI, 9.21%-22.38%; P  < .001), intrahepatic bile duct (APC, 8.12%; 95% CI, 4.94%-11.39%; P  < .001), and pancreas (APC, 2.53%; 95% CI, 1.69%-3.38%; P  < .001) (eTable 3 in Supplement 1 ). In contrast, the incidence rates of cancers of the liver and esophagus decreased, with APCs of −4.67% (95% CI, −5.70% to −3.63%; P  < .001) for liver cancer and −0.94% (95% CI, −2.56% to 0.71%; P  = .22) for esophageal cancer.

The number of incident cases and the incidence rates of early-onset gastrointestinal cancers by sex, age group, and race and ethnicity are shown in eTable 4A to 4C in Supplement 1 . Among both male and female individuals, the incidence rates of cancers of the appendix and intrahepatic bile duct increased significantly from 2010 to 2019, while the incidence rates of stomach cancers increased only in female individuals, and the incidence rates of gallbladder cancers increased only in male individuals.

By age, the greatest increase in incidence rates of early-onset gastrointestinal cancers occurred in those aged 30 to 39 years, with significant increases in cancers of the esophagus (APC, 6.86%; 95% CI, 1.77%-12.21%; P  = .01), small intestine (APC, 4.24%; 95% CI, 1.75%-6.78%; P  = .004), appendix (APC, 16.20%; 95% CI, 9.81%-22.96%; P  < .001), pancreas (APC, 4.47%; 95% CI, 1.23%-7.80%; P  = .01), and intrahepatic bile duct (APC, 8.88%; 95% CI, 2.56%-15.59%; P  = .01) (eTable 4B and eFigure 4 in Supplement 1 ).

By race and ethnicity, Hispanic people experienced the greatest increase in incidence rates of gastrointestinal cancers (APC, 3.08%; 95% CI, 2.09%-4.08%; P  < .001) followed by American Indian or Alaska Native people (APC, 2.83%; 95% CI, 0.51%-5.19%; P  = .02) and White people (APC, 2.45%; 95% CI, 1.75%-3.15%; P  < .001) (eTable 4C in Supplement 1 ). There were no significant increases in early-onset gastrointestinal cancers by specific sites among American Indian or Alaska Native people. Asian or Pacific Islander people experienced significant increases in the incidence of early-onset appendiceal cancers. Hispanic people had significant increases in stomach, appendiceal, colorectal, pancreatic, and intrahepatic bile duct cancers. Among Black people, the incidence of appendiceal and biliary cancer significantly increased. White people experienced significant increases in the incidence of appendiceal and intrahepatic bile duct cancers.

We next evaluated patterns in the APCs of early-onset cancer among 12 cancers identified as related to obesity by the Centers for Disease Control and Prevention 35 - 37 to assess the association between increasing obesity rates and the incidence of early-onset cancer (eFigure 5 and eTable 5 in Supplement 1 ). From 2010 to 2019, the APC of obesity-related early-onset cancer was 1.00% (95% CI, 0.69%-1.31%; P  < .001). The fastest-growing incidence rates of obesity-related cancers were in the pancreas (APC, 2.53%; 95% CI, 1.69%-3.38%; P  < .001), gallbladder (APC, 2.36%; 95% CI, −1.60% to 6.48%; P  = .21), and uterus (APC, 2.22%; 95% CI, 1.59%-2.85%; P  < .001). Conversely, the fastest-decreasing incidence rates among obesity-related cancers were in the liver (APC, 4.67%; 95% CI, −5.70% to −3.63%; P  < .001), ovary (APC, −1.03%; 95% CI, −2.15% to 0.10%; P  = .07), and esophagus (APC, −0.94%; 95% CI, −2.56% to 0.71%; P  = .22).

In this nationwide cohort study, we found that in 2019, a total of 56 468 early-onset cancers were diagnosed in the US. The overall incidence rate of early-onset cancers increased from 2010 to 2019, while the incidence rate of cancers declined among individuals 50 years and older. During the study period, the incidence rates of early-onset cancers increased in female individuals but declined in male individuals; this increase among female individuals was mainly due to cancers of the uterus and breast. By race and ethnicity, there was an increased incidence of early-onset cancer in American Indian or Alaska Native people, Asian or Pacific Islander people, and Hispanic people. However, the incidence of early-onset cancers remained stable among White people and declined among Black people. By age group, the incidence rate of early-onset cancers increased in individuals aged 30 to 39 years and remained stable in other age groups younger than 50 years.

In 2019, breast cancer had the highest number of incident early-onset cases. By organ system, gastrointestinal cancers had the fastest-growing incidence rates of early-onset cancer, followed by cancers of the urinary system and the female reproductive system. Among gastrointestinal cancers in 2019, the most common types of incident early-onset cancers were in the colon and/or rectum, stomach, and pancreas. During the study period, the gastrointestinal early-onset cancers with the fastest-growing incidence rates were in the appendix, intrahepatic bile duct, and pancreas.

These findings built upon previous US studies that provided data on patterns of early-onset cancer until 2014 24 and 2015. 27 These data are also consistent with a recent Global Burden of Disease Study, 3 which estimated that the highest age-standardized incident rates of early-onset cancer occurred in countries with a high sociodemographic index, such as those in North America. The current study expands on these data by providing granular updated patterns through 2019 by organ system, sex, and race and ethnicity. Several studies 7 , 22 , 38 - 46 have described an increase in specific early-onset cancers, such as those of the colon and/or rectum, breast, kidney, stomach, uterus, endometrium, and pancreas. However, there are limited data that provide a comprehensive updated overview of the latest patterns in early-onset cancer in the US, both overall and by organ system, and the current study fills this knowledge gap.

This nationwide study provides updated evidence that the incidence of early-onset cancers in the US is increasing and highlights several disparities. The increase in early-onset cancer disproportionately occurred among female individuals, American Indian or Alaska Native individuals, Asian or Pacific Islander individuals, and individuals aged 30 to 39 years. Further research is required to fully elucidate the reasons for these disparities. There is a need to inform health care professionals about the increasing incidence of early-onset cancer, and investigations for possible tumors need to be considered when clinically appropriate, even in patients younger than 50 years. These data will be useful for public health specialists and health care policy makers and serve as a call to action for further research into the various environmental factors that may be associated with this concerning pattern.

This study has strengths, including a large sample, data updated through 2019, and detailed subgroup analyses by organ system and individual cancer sites.

The study also has limitations. The generalizability of these findings to populations outside of the US may be unclear. There may have been misclassification, or there could have been underreporting or underdiagnosis among underserved populations, such as Black individuals; hence, these results require cautious interpretation. We recognize that although the Centers for Disease Control and Prevention included ovarian cancer in the group of cancers related to obesity, data regarding the association of body mass index with ovarian cancer are conflicting, with an individual participant data meta-analysis only finding an association between body mass index and ovarian cancer among people who had never used hormonal therapy. 34 , 47

This nationwide cohort study found that the incidence of early-onset cancers continued to increase in the US from 2010 to 2019. While breast cancer had the highest number of incident cases, gastrointestinal cancers had the fastest-growing incidence rates among all early-onset cancers. These data may have implications for the development of surveillance strategies and funding priorities.

Accepted for Publication: June 26, 2023.

Published: August 16, 2023. doi:10.1001/jamanetworkopen.2023.28171

Open Access: This is an open access article distributed under the terms of the CC-BY License . © 2023 Koh B et al. JAMA Network Open .

Corresponding Authors: Daniel Q. Huang, MBBS, MMED, Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, National University Health System, 1E Kent Ridge Rd, Singapore 119228, Singapore ( [email protected] ); Cheng Han Ng, MBBS, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 10 Medical Dr, Singapore 117597, Singapore ( [email protected] ).

Author Contributions: Mr Koh and Dr Huang had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: B. Koh, Ng, Lim, J. Koh, Syn, Wijarnpreecha, Chong, Muthiah, Yeoh, Loomba, Huang.

Acquisition, analysis, or interpretation of data: B. Koh, Tan, Ng, Fu, Zeng, Yong, Meng, Liu, Luu, Vogel, Singh, Huang.

Drafting of the manuscript: B. Koh, Ng, Fu, Lim, Zeng, J. Koh, Loomba, Huang.

Critical review of the manuscript for important intellectual content: B. Koh, Tan, Ng, Yong, Syn, Meng, Wijarnpreecha, Liu, Chong, Muthiah, Luu, Vogel, Singh, Yeoh, Loomba, Huang.

Statistical analysis: B. Koh, Tan, Ng, Fu, Yong, J. Koh, Luu, Huang.

Obtained funding: Ng, Huang.

Administrative, technical, or material support: Tan, Lim, Zeng, Yong, J. Koh, Muthiah, Huang.

Supervision: Syn, Wijarnpreecha, Liu, Chong, Muthiah, Loomba, Huang.

Conflict of Interest Disclosures: Mr Ng reported receiving personal fees from Boxer Capital outside the submitted work. Dr Muthiah reported receiving grants from the National Medical Research Council (Singapore) during the conduct of the study. Dr Vogel reported receiving personal fees from AstraZeneca, BeiGene, Boehringer Mannheim, Bristol Myers Squibb, Eisai Co, Incyte, MSD, Pierre Fabre, and Roche outside the submitted work. Dr Singh reported receiving grants from AbbVie and Pfizer and personal fees from Pfizer outside the submitted work. Dr Yeoh reported serving as a member of the MiRXES Scientific Advisory Board outside the submitted work. Dr Loomba reported receiving grants from Arrowhead Pharmaceuticals, AstraZeneca, Boehringer Ingelheim, Bristol Myers Squibb, Eli Lilly and Company, Galectin Therapeutics, Galmed Pharmaceuticals, Gilead Sciences, Hanmi Pharmaceutical Co, Intercept Pharmaceuticals, Inventiva, Ionis Pharmaceuticals, Janssen Pharmaceuticals, Madrigal Pharmaceuticals, Merck & Co, NGM Biopharmaceuticals, Novo Nordisk, Pfizer, Sonic Incytes, and Terns Pharmaceuticals and serving as a consultant for 89bio, Aardvark Therapeutics, Altimmune, Alnylam/Regeneron, Amgen, Arrowhead Pharmaceuticals, AstraZeneca, Bristol Myers Squibb, CohBar, Eli Lilly and Company, Galmed Pharmaceuticals, Gilead Sciences, Glympse Bio, Hightide Therapeutics, Inipharm, Intercept Pharmaceuticals, Inventiva, Ionis Pharmaceuticals, Janssen Pharmaceuticals, Madrigal Pharmaceuticals, Metacrine, NGM Biopharmaceuticals, Novartis, Novo Nordisk, Merck & Co, Pfizer, Sagimet Biosciences, Theratechnologies, Terns Pharmaceuticals, and Viking Therapeutics during the conduct of the study; owning stock options in 89bio and Sagimet Biosciences and being a cofounder of LipoNexus outside the submitted work. Dr Huang reported receiving personal fees from Gilead Sciences outside the submitted work. No other disclosures were reported.

Funding/Support: This study was supported by grants 5UL1TR001442 from the National Center for Advancing Translational Sciences (Dr Loomba); U01DK061734, U01DK130190, R01DK106419, R01DK121378, R01DK124318, and P30DK120515 from the National Institute of Diabetes and Digestive and Kidney Diseases (Dr Loomba); and MOH-000595-01 from the National Medical Research Council of the Singapore Ministry of Health under its NMRC Research Training Fellowship (Dr Huang).

Role of the Funder/Sponsor: The funding organizations had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Data Sharing Statement: See Supplement 2 .

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Computer Science > Artificial Intelligence

Title: vision language models are blind.

Abstract: Large language models with vision capabilities (VLMs), e.g., GPT-4o and Gemini 1.5 Pro are powering countless image-text applications and scoring high on many vision-understanding benchmarks. We propose BlindTest, a suite of 7 visual tasks absurdly easy to humans such as identifying (a) whether two circles overlap; (b) whether two lines intersect; (c) which letter is being circled in a word; and (d) counting the number of circles in a Olympic-like logo. Surprisingly, four state-of-the-art VLMs are, on average, only 56.20% accurate on our benchmark, with \newsonnet being the best (73.77% accuracy). On BlindTest, VLMs struggle with tasks that requires precise spatial information and counting (from 0 to 10), sometimes providing an impression of a person with myopia seeing fine details as blurry and making educated guesses. Code is available at: this https URL

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