Clinical trials data
Stroop Color-Word Test in healthy volunteer trials: 98 registered studies
Every registered healthy volunteers study on ClinicalTrials.gov that names the Stroop Color-Word Test in an outcome measure: how often it is a primary outcome, the tests named with it, how large the studies are and when they measure it.
- Registered healthy volunteers studies name it in an outcome measure
- 98
- Name it in a primary outcome, 49%
- 48 of 98
Tests named in the same studies
- 1
Trail Making Test31 studies, 16 as a primary outcome
- 2
Digit Span Test20 studies, 10 as a primary outcome
- 3
Card Sorting Test (Berg)12 studies, 5 as a primary outcome
- 4
Verbal Fluency9 studies, 1 as a primary outcome
- 5
Symbol Coding8 studies, 2 as a primary outcome
- 6
Go/No-Go Task7 studies, 4 as a primary outcome
- 7
Task Switching Test6 studies, 4 as a primary outcome
- 8
Eriksen Flanker Task6 studies, 3 as a primary outcome
- 9
N-Back Task6 studies, 3 as a primary outcome
- 10
Verbal Learning5 studies, 2 as a primary outcome
A test as a primary outcomeOnly in secondary or other outcomes
Studies by start year
A test as a primary outcomeOnly in secondary or other outcomes
Show as a table
| Start year | Studies | A test as a primary outcome |
|---|---|---|
| 2000 | 0 | 0 |
| 2001 | 0 | 0 |
| 2002 | 1 | 0 |
| 2003 | 0 | 0 |
| 2004 | 0 | 0 |
| 2005 | 0 | 0 |
| 2006 | 1 | 1 |
| 2007 | 0 | 0 |
| 2008 | 0 | 0 |
| 2009 | 0 | 0 |
| 2010 | 2 | 1 |
| 2011 | 2 | 0 |
| 2012 | 2 | 1 |
| 2013 | 1 | 0 |
| 2014 | 1 | 1 |
| 2015 | 7 | 2 |
| 2016 | 2 | 1 |
| 2017 | 3 | 0 |
| 2018 | 9 | 5 |
| 2019 | 5 | 2 |
| 2020 | 4 | 1 |
| 2021 | 8 | 4 |
| 2022 | 10 | 7 |
| 2023 | 9 | 5 |
| 2024 | 10 | 5 |
| 2025 | 13 | 7 |
| 2026 | 8 | 5 |
Phases and study sizes
By phase
- Phase 15 studies, 0 as a primary outcome
- Phase 1/21 studies, 0 as a primary outcome
- Phase 22 studies, 1 as a primary outcome
- Phase 33 studies, 2 as a primary outcome
- Phase 42 studies, 0 as a primary outcome
- Not applicable80 studies, 43 as a primary outcome
- Observational5 studies, 2 as a primary outcome
Participants per study
- Not applicable60 median, 36 to 85
Show as a table
| Phase | Studies with a size | Median | Middle half |
|---|---|---|---|
| Not applicable | 80 | 60 | 36 to 85 |
When healthy volunteer trials measure it
Latest time point of each outcome
- Within a day22 outcomes, 10 as a primary outcome
- Up to 4 weeks26 outcomes, 17 as a primary outcome
- 1 to 3 months24 outcomes, 9 as a primary outcome
- 3 to 6 months11 outcomes, 5 as a primary outcome
- 6 to 12 months3 outcomes, 1 as a primary outcome
- 1 to 2 years1 outcomes, 0 as a primary outcome
- Over 2 years1 outcomes, 0 as a primary outcome
- No duration given10 outcomes, 6 as a primary outcome
A test as a primary outcomeOnly in secondary or other outcomes
88 of the 98 outcome measures give a duration. A single visit counts as within a day.
Status, results, interventions and countries
Status
- Recruiting10 studies, 7 as a primary outcome
- Not yet recruiting5 studies, 4 as a primary outcome
- Active, not recruiting6 studies, 2 as a primary outcome
- Completed62 studies, 28 as a primary outcome
- Stopped early2 studies, 1 as a primary outcome
- Status unknown13 studies, 6 as a primary outcome
What they test
- Behavioral29 studies, 19 as a primary outcome
- Drug11 studies, 2 as a primary outcome
- Device8 studies, 4 as a primary outcome
- Dietary supplement14 studies, 8 as a primary outcome
- Diagnostic test1 studies, 0 as a primary outcome
- Other39 studies, 18 as a primary outcome
Intervention types as registered. A study can list several; observational studies often list none.
Where their sites are
- United States17 studies, 7 as a primary outcome
- Türkiye14 studies, 9 as a primary outcome
- Taiwan5 studies, 3 as a primary outcome
- Belgium4 studies, 4 as a primary outcome
- Spain4 studies, 2 as a primary outcome
- Switzerland4 studies, 1 as a primary outcome
- Australia3 studies, 0 as a primary outcome
- Canada3 studies, 1 as a primary outcome
- France3 studies, 0 as a primary outcome
- Italy3 studies, 1 as a primary outcome
- Portugal3 studies, 2 as a primary outcome
- United Kingdom3 studies, 0 as a primary outcome
32 countries in all. A study with sites in several counts in each; 8 list no site.
Reported results
Completed studies with results posted on ClinicalTrials.gov, a results paper the registry links to the study, or both.
Completed healthy volunteers studies that name the Stroop Color-Word Test: 16 of 62, 26%
Every completed study with a cognitive outcome: 3,626 of 7,953, 46%
| Results | Completed healthy volunteers studies that name the Stroop Color-Word Test | Every completed study |
|---|---|---|
| Results on ClinicalTrials.gov and a paper | 0, 0% | 776, 10% |
| Results on ClinicalTrials.gov only | 2, 3% | 1,139, 14% |
| A results paper only | 14, 23% | 1,711, 22% |
| Neither | 46, 74% | 4,327, 54% |
The 98 studies
98 studies match. 48 name the Stroop Color-Word Test in a primary outcome. Median size 60 participants. Median time to the primary outcome: 4 weeks.
Loading 98 studies; the filters turn on when they arrive.
2026 is partly planned starts.
Show as a table
| Start year | Studies | As a primary outcome |
|---|---|---|
| 2000 | 0 | 0 |
| 2001 | 0 | 0 |
| 2002 | 1 | 0 |
| 2003 | 0 | 0 |
| 2004 | 0 | 0 |
| 2005 | 0 | 0 |
| 2006 | 1 | 1 |
| 2007 | 0 | 0 |
| 2008 | 0 | 0 |
| 2009 | 0 | 0 |
| 2010 | 2 | 1 |
| 2011 | 2 | 0 |
| 2012 | 2 | 1 |
| 2013 | 1 | 0 |
| 2014 | 1 | 1 |
| 2015 | 7 | 2 |
| 2016 | 2 | 1 |
| 2017 | 3 | 0 |
| 2018 | 9 | 5 |
| 2019 | 5 | 2 |
| 2020 | 4 | 1 |
| 2021 | 8 | 4 |
| 2022 | 10 | 7 |
| 2023 | 9 | 5 |
| 2024 | 10 | 5 |
| 2025 | 13 | 7 |
| 2026 | 8 | 5 |
Library tests named most
Largest condition groups
Phases
Participants
Lead sponsor: industry 9, NIH 1, other 88. Interventional 93, observational 5.
As a primary outcomeSecondary or other outcomeThe Stroop Color-Word Test
The studies, newest registration first
Each number opens the study's record on ClinicalTrials.gov.
| Study | Start | Phase | Conditions | Participants | Lead sponsor | Status | Library tests named, with the latest time point |
|---|---|---|---|---|---|---|---|
| NCT07897175 | Start2026 | PhaseNot applicable | ConditionsHealthy volunteers | Participants54 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07879703 | Start2018 | PhaseNot applicable | ConditionsHealthy volunteers | Participants120 | Lead sponsorOther | StatusCompleted | Library tests named
|
| NCT07809412 | Start2025 | PhaseNot applicable | ConditionsHealthy volunteers | Participants20 | Lead sponsorOther | StatusCompleted | Library tests named
|
| NCT07706283 | Start2025 | PhaseNot applicable | ConditionsHealthy volunteers, Sleep and sleep disorders, Pain and fatigue | Participants81 | Lead sponsorOther | StatusCompleted | Library tests named
|
| NCT07698652 | Start2026 | PhaseNot applicable | ConditionsHealthy volunteers | Participants60 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07650006 | Start2026 | PhaseNot applicable | ConditionsHealthy volunteers | Participants30 | Lead sponsorOther | StatusCompleted | Library tests named
|
| NCT07625371 | Start2024 | PhaseNot applicable | ConditionsHealthy volunteers, Aging, frailty and exercise | Participants40 | Lead sponsorOther | StatusCompleted | Library tests named
|
| NCT07611422 | Start2026 | PhaseNot applicable | ConditionsHealthy volunteers | Participants120 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07572240 | Start2026 | PhaseNot applicable | ConditionsHealthy volunteers | Participants72 | Lead sponsorIndustry | StatusActive, not recruiting | Library tests named
|
| NCT07556250 | Start2026 | PhaseNot applicable | ConditionsHealthy volunteers | Participants225 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07548541 | Start2025 | PhaseNot applicable | ConditionsHealthy volunteers | Participants18 | Lead sponsorOther | StatusCompleted | Library tests named
|
| NCT07462715 | Start2026 | PhasePhase 4 | ConditionsHealthy volunteers | Participants100 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07443904 | Start2026 | PhaseNot applicable | ConditionsHealthy volunteers | Participants297 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07434830 | Start2025 | PhaseObservational | ConditionsHealthy volunteers | Participants119 | Lead sponsorOther | StatusCompleted | Library tests named
|
| NCT07424365 | Start2025 | PhaseNot applicable | ConditionsMild cognitive impairment, Parkinson's disease, Healthy volunteers | Participants80 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07335848 | Start2023 | PhaseNot applicable | ConditionsHealthy volunteers | Participants36 | Lead sponsorOther | StatusCompleted | Library tests named
|
| NCT07267845 | Start2025 | PhaseNot applicable | ConditionsHealthy volunteers | Participants80 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07225413 | Start2022 | PhaseNot applicable | ConditionsHealthy volunteers | Participants27 | Lead sponsorOther | StatusCompleted | Library tests named
|
| NCT07211269 | Start2025 | PhaseNot applicable | ConditionsHealthy volunteers | Participants40 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07189130 | Start2025 | PhaseNot applicable | ConditionsHealthy volunteers, Aging, frailty and exercise | Participants24 | Lead sponsorOther | StatusActive, not recruiting | Library tests named
|
| NCT07144930 | Start2025 | PhaseNot applicable | ConditionsStroke, Healthy volunteers | Participants210 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07134517 | Start2025 | PhaseNot applicable | ConditionsHealthy volunteers | Participants42 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07130825 | Start2025 | PhaseNot applicable | ConditionsHealthy volunteers | Participants60 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07119762 | Start2025 | PhaseNot applicable | ConditionsHealthy volunteers | Participants67 | Lead sponsorOther | StatusCompleted | Library tests named
|
| NCT07119684 | Start2024 | PhaseNot applicable | ConditionsHealthy volunteers | Participants35 | Lead sponsorOther | StatusCompleted | Library tests named
|
Questions, answered from the data
How many healthy volunteer trials use the Stroop Color-Word Test?
98 registered healthy volunteers studies on ClinicalTrials.gov name it in an outcome measure, 48 of them in a primary outcome: 15% of the condition's 656 studies with a cognitive outcome, against 12% of all of them. It is the test healthy volunteer trials name most.
Which tests do healthy volunteer trials use with the Stroop Color-Word Test?
The Trail Making Test (31 studies), the Digit Span Test (20 studies) and the Card Sorting Test (Berg) (12 studies).
When do healthy volunteer trials measure the Stroop Color-Word Test?
Half of the primary outcomes that name the Stroop Color-Word Test are measured within 4 weeks of the start, and the middle half from 3 days to 8 weeks. 42 primary outcomes give a duration.
How many completed healthy volunteer trials that use the Stroop Color-Word Test have reported results?
16 of the 62 completed studies that name it, 26%, have reported results: 2 posted them on ClinicalTrials.gov, 14 have a results paper linked to the registry record, and 0 did both. The other 46 show neither. Of all completed studies with a cognitive outcome, 46% have reported results.
How the studies are counted
For each test family, the census runs ClinicalTrials.gov's own outcome search for the family's names and reads every study first posted by the day the family was counted. These studies were read on 10 November 2026. A study counts once on a page, however many tests it names. Counts for a test cover every version of the task under any of its names, so a page can count studies that used a commercial version.
The census adds two things to each record and changes nothing in it: which outcome list names the test (primary, then secondary, then other), and the condition groups, matched on the study's condition names and MeSH terms. A study can fall in several groups; one whose only condition is cognitive impairment or decline falls in “Cognitive impairment and decline”. Studies that name only instruments outside the library count in every total and share but are not listed.
A second read on 10 November 2026 added each study's overall status, whether results are posted, its intervention types, the countries of its sites and the time frame of the outcome that names each test. A time frame counts by the latest time point it names: “Baseline, 12 and 24 weeks” is 24 weeks, a single visit is within a day, and one that names no duration, such as “end of treatment”, is left out of the timings.
A third read on 10 November 2026 added the papers the registry links to each study: those its sponsor lists as reporting results, and those PubMed links to it through the study's NCT number. A study has a results paper when one of them came out in or after the month of its primary completion and PubMed does not class it as a protocol, review or comment. A paper that never gives the NCT number is not linked, so some studies counted as reporting neither did publish.
Source: ClinicalTrials.gov, a database of the U.S. National Library of Medicine, which does not endorse these pages. Every study line is in the data release 2.1.0, and the explorer's own file is clinical-trials-studies.json.
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