Research data · 2026 report
How behavioral test papers changed in ten years
In 2021 to 2025, more papers that mention a behavioral test used mice than rats, the reverse of 2011 to 2015.
Each finding counts animal research papers that mention one of 90 behavioral tests in their title or abstract, as PubMed listed them on November 8, 2026.
Mice overtook rats in 2020
Mice have led every year since.
Papers that mention a behavioral test, mice and rats, 2001 to 2025
When PubMed's indexing names a paper's species, we use it. Otherwise PubTator 3, NCBI's text-mining service, has to find a species in the title or abstract, or the paper is not counted.
- Mouse
- Rat
Show the counts for each year and species
| Year | Mouse | Rat |
|---|---|---|
| 2001 | 700 | 1,516 |
| 2002 | 732 | 1,559 |
| 2003 | 856 | 1,687 |
| 2004 | 949 | 1,809 |
| 2005 | 1,020 | 1,955 |
| 2006 | 1,150 | 1,949 |
| 2007 | 1,222 | 2,044 |
| 2008 | 1,426 | 2,226 |
| 2009 | 1,501 | 2,197 |
| 2010 | 1,648 | 2,335 |
| 2011 | 1,849 | 2,605 |
| 2012 | 2,091 | 2,729 |
| 2013 | 2,329 | 2,954 |
| 2014 | 2,310 | 3,030 |
| 2015 | 2,349 | 2,928 |
| 2016 | 2,542 | 2,911 |
| 2017 | 2,624 | 2,931 |
| 2018 | 2,747 | 2,937 |
| 2019 | 2,859 | 2,954 |
| 2020 | 3,043 | 3,005 |
| 2021 | 3,353 | 2,998 |
| 2022 | 3,142 | 2,791 |
| 2023 | 2,996 | 2,444 |
| 2024 | 3,209 | 2,548 |
| 2025 | 3,862 | 2,799 |
Zebrafish papers grew fastest of any species
Zebrafish were used in 234 of the 245 papers from 2021 to 2025 that mention the novel tank test, and that test's papers grew to 5.3 times as many as in 2011 to 2015.
Papers that mention a test, by species
- 2011 to 2015
- 2021 to 2025, a rise
- 2021 to 2025, a fall
A change of less than 5% either way counts as about the same.
The tests that grew the most
Among tests with 100 or more papers from 2021 to 2025, these grew the most compared with 2011 to 2015.
- 2011 to 2015
- 2021 to 2025, a rise
- 2021 to 2025, a fall
The tests that fell the most
Among tests with 100 or more papers in 2011 to 2015, these fell the most by 2021 to 2025.
- 2011 to 2015
- 2021 to 2025, a rise
- 2021 to 2025, a fall
A larger share used both sexes
Among the subject headings PubMed gives a paper are the tags Male and Female, for the sex of the animals studied. Each bar splits the tagged papers into both sexes, males only and females only.
Papers that mention a test, in each period
- Both sexes
- Males only
- Females only
These shares leave out papers whose subject headings carry no sex tag, and papers with no subject headings. Of the papers from 2021 to 2025 with subject headings, 9,084, or 35%, carried no sex tag. In 2011 to 2015 that share was half as large, so the rise from 18% to 24% using both sexes may not compare exactly.
The tests that moved most toward both sexes
Each row is one of the 37 tests with 100 or more tagged papers in both periods. It shows the share that used both sexes in 2011 to 2015, then in 2021 to 2025.
Papers by year, with 2026 so far
Papers that mention a test grew to 1.2 times as many: 32,277 in 2021 to 2025, up from 26,411 in 2011 to 2015.
Animal research papers that mention a behavioral test, by year, 2001 to 2026
The 2026 bar counts papers added to PubMed by November 8, 2026.
- Papers in a full year
- 2026 so far
Show the counts for each year
| Year | Papers |
|---|---|
| 2001 | 2,404 |
| 2002 | 2,552 |
| 2003 | 2,746 |
| 2004 | 2,952 |
| 2005 | 3,189 |
| 2006 | 3,357 |
| 2007 | 3,469 |
| 2008 | 3,881 |
| 2009 | 3,948 |
| 2010 | 4,183 |
| 2011 | 4,606 |
| 2012 | 5,076 |
| 2013 | 5,516 |
| 2014 | 5,631 |
| 2015 | 5,582 |
| 2016 | 5,758 |
| 2017 | 5,880 |
| 2018 | 6,100 |
| 2019 | 6,182 |
| 2020 | 6,461 |
| 2021 | 6,786 |
| 2022 | 6,374 |
| 2023 | 5,863 |
| 2024 | 6,139 |
| 2025 | 7,115 |
| 2026 (part year) | 6,543 |
Papers that mention a test fell from 6,786 in 2021 to 5,863 in 2023, then rose to 7,115 in 2025. Part of this dip may come from PubMed's indexing rather than from fewer studies. A paper PubMed has not indexed counts here only if PubTator 3 finds its species. Papers that PubMed indexed under the subject heading Animals also fell and rose, from 200,221 in 2021 to 156,447 in 2023 and 235,479 in 2025.
More from the same papers
- 11,697 of the 32,277 papers from 2021 to 2025 mention two or more tests Build a test battery
- 5,033 of the 32,277 papers from 2021 to 2025 were NIH-funded NIH funding behind the papers
- 24 of the 5,392 papers from 2021 to 2025 that mention the Morris water maze are meta-analyses, the most of any test The animals' sex, meta-analyses and retractions
