Clinical trials data
Cognitive tests in mild cognitive impairment trials: 859 registered studies
Every registered mild cognitive impairment study on ClinicalTrials.gov that names a cognitive test in an outcome measure: the tests used most, how often as a primary outcome, which tests go together, how large the studies are and when they measure the outcome.
- Registered mild cognitive impairment studies name a cognitive test in an outcome
- 859
- Led by industry
- 64
The tests mild cognitive impairment trials use most
The Trail Making Test leads: 213 of the 859 studies name it, 25%. Next comes Verbal Learning (183). As a primary outcome, Verbal Learning leads with 101 studies.
- 1
Trail Making Test213 studies, 82 as a primary outcome
- 2
Verbal Learning183 studies, 101 as a primary outcome
- 3
Verbal Fluency177 studies, 70 as a primary outcome
- 4
Digit Span Test169 studies, 77 as a primary outcome
- 5
Stroop Color-Word Test126 studies, 50 as a primary outcome
- 6
Category Fluency92 studies, 39 as a primary outcome
- 7
Symbol Coding84 studies, 38 as a primary outcome
- 8
Short Story Recall74 studies, 35 as a primary outcome
- 9
Picture Naming Test71 studies, 23 as a primary outcome
- 10
Selective Reminding Task48 studies, 25 as a primary outcome
- 11
N-Back Task42 studies, 18 as a primary outcome
- 12
Clock Drawing Task41 studies, 20 as a primary outcome
- 13
Complex Figure Copy and Recall31 studies, 11 as a primary outcome
- 14
Task Switching Test22 studies, 12 as a primary outcome
- 15
Continuous Performance Test17 studies, 11 as a primary outcome
- 16
Face-name Memory Task16 studies, 11 as a primary outcome
- 17
Go/No-Go Task16 studies, 4 as a primary outcome
- 18
Card Sorting Test (Berg)15 studies, 8 as a primary outcome
- 19
Delayed Recall Module14 studies, 7 as a primary outcome
- 20
Mnemonic Similarity Task13 studies, 7 as a primary outcome
- 21
Corsi Block-Tapping Test13 studies, 6 as a primary outcome
- 22
Matrix Reasoning13 studies, 5 as a primary outcome
- 23
Arithmetic Fluency Task11 studies, 7 as a primary outcome
- 24
Paired Associate Learning11 studies, 2 as a primary outcome
- 25
Word Pair Learning10 studies, 7 as a primary outcome
A test as a primary outcomeOnly in secondary or other outcomes
30% of mild cognitive impairment studies name only instruments outside the library, such as clinician-administered screening scales. They count in every figure on this page and are not listed. The explorer below holds all 86 tests.
Tests used together
- Digit Span Test and Trail Making Test95 studies name both
- Trail Making Test and Verbal Fluency86 studies name both
- Trail Making Test and Verbal Learning84 studies name both
- Verbal Fluency and Verbal Learning69 studies name both
- Digit Span Test and Verbal Fluency67 studies name both
- Stroop Color-Word Test and Trail Making Test64 studies name both
- Digit Span Test and Verbal Learning59 studies name both
- Category Fluency and Trail Making Test51 studies name both
- Category Fluency and Verbal Fluency48 studies name both
- Stroop Color-Word Test and Verbal Fluency48 studies name both
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 | 1 |
| 2003 | 1 | 1 |
| 2004 | 0 | 0 |
| 2005 | 1 | 0 |
| 2006 | 3 | 2 |
| 2007 | 0 | 0 |
| 2008 | 8 | 5 |
| 2009 | 5 | 3 |
| 2010 | 13 | 7 |
| 2011 | 18 | 9 |
| 2012 | 21 | 12 |
| 2013 | 10 | 6 |
| 2014 | 18 | 10 |
| 2015 | 34 | 22 |
| 2016 | 30 | 17 |
| 2017 | 33 | 18 |
| 2018 | 43 | 32 |
| 2019 | 54 | 33 |
| 2020 | 54 | 35 |
| 2021 | 67 | 44 |
| 2022 | 67 | 39 |
| 2023 | 81 | 42 |
| 2024 | 102 | 71 |
| 2025 | 100 | 53 |
| 2026 | 94 | 46 |
Phases and sponsors
By phase
- Early phase 16 studies, 5 as a primary outcome
- Phase 116 studies, 6 as a primary outcome
- Phase 1/213 studies, 7 as a primary outcome
- Phase 278 studies, 36 as a primary outcome
- Phase 2/35 studies, 5 as a primary outcome
- Phase 312 studies, 7 as a primary outcome
- Phase 424 studies, 9 as a primary outcome
- Not applicable593 studies, 378 as a primary outcome
- Observational112 studies, 55 as a primary outcome
Sponsors and study types
Lead sponsor: industry 64, NIH 2, universities, hospitals and others 793. Interventional 747, observational 112.
Status, results, interventions and countries
Status
- Recruiting182 studies, 100 as a primary outcome
- Not yet recruiting80 studies, 44 as a primary outcome
- Active, not recruiting32 studies, 19 as a primary outcome
- Completed365 studies, 225 as a primary outcome
- Stopped early44 studies, 24 as a primary outcome
- Status unknown156 studies, 96 as a primary outcome
What they test
- Behavioral267 studies, 175 as a primary outcome
- Drug135 studies, 60 as a primary outcome
- Device200 studies, 124 as a primary outcome
- Dietary supplement49 studies, 29 as a primary outcome
- Procedure18 studies, 9 as a primary outcome
- Diagnostic test22 studies, 7 as a primary outcome
- Biological9 studies, 4 as a primary outcome
- Radiation3 studies, 2 as a primary outcome
- Combination product11 studies, 8 as a primary outcome
- Genetic2 studies, 1 as a primary outcome
- Other233 studies, 146 as a primary outcome
- None given52 studies, 25 as a primary outcome
Intervention types as registered. A study can list several; observational studies often list none.
Where their sites are
- United States273 studies, 166 as a primary outcome
- China74 studies, 44 as a primary outcome
- Italy48 studies, 26 as a primary outcome
- Canada47 studies, 19 as a primary outcome
- Taiwan45 studies, 33 as a primary outcome
- Hong Kong44 studies, 29 as a primary outcome
- Spain43 studies, 21 as a primary outcome
- South Korea28 studies, 15 as a primary outcome
- Switzerland24 studies, 10 as a primary outcome
- United Kingdom22 studies, 7 as a primary outcome
- Germany21 studies, 8 as a primary outcome
- Singapore16 studies, 9 as a primary outcome
59 countries in all. A study with sites in several counts in each; 68 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 mild cognitive impairment studies: 161 of 365, 44%
Every completed study with a cognitive outcome: 3,626 of 7,953, 46%
| Results | Completed mild cognitive impairment studies | Every completed study |
|---|---|---|
| Results on ClinicalTrials.gov and a paper | 38, 10% | 776, 10% |
| Results on ClinicalTrials.gov only | 57, 16% | 1,139, 14% |
| A results paper only | 66, 18% | 1,711, 22% |
| Neither | 204, 56% | 4,327, 54% |
How many participants they enroll
- Phase 128 median, 18 to 39
- Phase 1/225 median, 20 to 64
- Phase 279 median, 46 to 149
- Phase 3206 median, 61 to 348
- Phase 486 median, 35 to 161
- Not applicable64 median, 40 to 120
- Observational180 median, 81 to 725
Show as a table
| Phase | Studies with a size | Median | Middle half |
|---|---|---|---|
| Phase 1 | 14 | 28 | 18 to 39 |
| Phase 1/2 | 13 | 25 | 20 to 64 |
| Phase 2 | 74 | 79 | 46 to 149 |
| Phase 3 | 12 | 206 | 61 to 348 |
| Phase 4 | 23 | 86 | 35 to 161 |
| Not applicable | 587 | 64 | 40 to 120 |
| Observational | 111 | 180 | 81 to 725 |
When the cognitive outcome is measured
Latest time point of each outcome
- Within a day101 outcomes, 50 as a primary outcome
- Up to 4 weeks180 outcomes, 66 as a primary outcome
- 1 to 3 months427 outcomes, 235 as a primary outcome
- 3 to 6 months344 outcomes, 160 as a primary outcome
- 6 to 12 months318 outcomes, 93 as a primary outcome
- 1 to 2 years135 outcomes, 65 as a primary outcome
- Over 2 years84 outcomes, 24 as a primary outcome
- No duration given111 outcomes, 58 as a primary outcome
A test as a primary outcomeOnly in secondary or other outcomes
1,589 of the 1,700 outcome measures give a duration. A single visit counts as within a day.
Median time to the primary outcome, by test
| Test | Primary outcomes | Median |
|---|---|---|
| Verbal Learning | 95 | 4 months |
| Trail Making Test | 75 | 13 weeks |
| Digit Span Test | 69 | 13 weeks |
| Verbal Fluency | 65 | 5 months |
| Stroop Color-Word Test | 46 | 13 weeks |
| Category Fluency | 35 | 6 months |
| Symbol Coding | 35 | 6 months |
| Short Story Recall | 33 | 6 months |
| Picture Naming Test | 23 | 6 months |
| Selective Reminding Task | 22 | 6 months |
Explore the mild cognitive impairment studies
598 studies match. 334 name a library test in a primary outcome. Median size 66 participants. Median time to the primary outcome: 13 weeks.
Loading 598 studies; the filters turn on when they arrive.
2026 is partly planned starts. Not shown: 1 planned to start after 2026.
Show as a table
| Start year | Studies | As a primary outcome |
|---|---|---|
| 2000 | 0 | 0 |
| 2001 | 0 | 0 |
| 2002 | 1 | 1 |
| 2003 | 1 | 1 |
| 2004 | 0 | 0 |
| 2005 | 1 | 0 |
| 2006 | 2 | 2 |
| 2007 | 0 | 0 |
| 2008 | 8 | 5 |
| 2009 | 5 | 3 |
| 2010 | 11 | 7 |
| 2011 | 14 | 6 |
| 2012 | 20 | 11 |
| 2013 | 9 | 5 |
| 2014 | 11 | 9 |
| 2015 | 23 | 14 |
| 2016 | 22 | 14 |
| 2017 | 26 | 13 |
| 2018 | 34 | 22 |
| 2019 | 44 | 26 |
| 2020 | 39 | 21 |
| 2021 | 52 | 34 |
| 2022 | 42 | 21 |
| 2023 | 57 | 29 |
| 2024 | 66 | 41 |
| 2025 | 57 | 23 |
| 2026 | 52 | 26 |
Library tests named most
Largest condition groups
Phases
Participants
Lead sponsor: industry 46, NIH 1, other 551. Interventional 543, observational 55.
As a primary outcomeSecondary or other outcome
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 |
|---|---|---|---|---|---|---|---|
| NCT07885085 | Start2027 | PhaseObservational | ConditionsMild cognitive impairment, Substance use and addiction, Delirium, surgery and intensive care, Pain and fatigue | Participants552 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07883148 | Start2024 | PhaseNot applicable | ConditionsDementia and Alzheimer's, Mild cognitive impairment | Participants52 | Lead sponsorOther | StatusCompleted | Library tests named
|
| NCT07882901 | Start2026 | PhasePhase 2 | ConditionsMild cognitive impairment | Participants44 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07865260 | Start2026 | PhaseNot applicable | ConditionsMild cognitive impairment, Stroke, Parkinson's disease | Participants80 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07863518 | Start2024 | PhaseNot applicable | ConditionsMild cognitive impairment | Participants61 | Lead sponsorOther | StatusCompleted | Library tests named
|
| NCT07856043 | Start2026 | PhasePhase 1 | ConditionsDementia and Alzheimer's, Mild cognitive impairment, Cardiovascular disease | Participants18 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07842146 | Start2026 | PhaseNot applicable | ConditionsDementia and Alzheimer's, Mild cognitive impairment | Participants60 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07827963 | Start2026 | PhaseObservational | ConditionsMild cognitive impairment, Parkinson's disease | Participants80 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07824128 | Start2026 | PhaseNot applicable | ConditionsDementia and Alzheimer's, Mild cognitive impairment, Parkinson's disease | Participants120 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07799584 | Start2026 | PhaseNot applicable | ConditionsMild cognitive impairment | Participants120 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07786116 | Start2025 | PhaseNot applicable | ConditionsDementia and Alzheimer's, Mild cognitive impairment, Parkinson's disease, Sleep and sleep disorders | Participants215 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07775079 | Start2026 | PhaseNot applicable | ConditionsMild cognitive impairment | Participants96 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07766993 | Start2026 | PhaseNot applicable | ConditionsDementia and Alzheimer's, Mild cognitive impairment | Participants100 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07764250 | Start2026 | PhaseNot applicable | ConditionsMild cognitive impairment | Participants96 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07752316 | Start2024 | PhaseNot applicable | ConditionsMild cognitive impairment | Participants30 | Lead sponsorOther | StatusCompleted | Library tests named
|
| NCT07735910 | Start2026 | PhaseNot applicable | ConditionsMild cognitive impairment, Depression and bipolar disorder, Sleep and sleep disorders, Anxiety, PTSD and OCD | Participants60 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07733726 | Start2025 | PhaseNot applicable | ConditionsMild cognitive impairment, Aging, frailty and exercise | Participants66 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07731334 | Start2026 | PhaseNot applicable | ConditionsDementia and Alzheimer's, Mild cognitive impairment | Participants384 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07718945 | Start2024 | PhaseNot applicable | ConditionsMild cognitive impairment | Participants55 | Lead sponsorOther | StatusCompleted | Library tests named
|
| NCT07688382 | Start2026 | PhaseNot applicable | ConditionsMild cognitive impairment | Participants70 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07672977 | Start2025 | PhaseNot applicable | ConditionsDementia and Alzheimer's, Mild cognitive impairment | Participants30 | Lead sponsorIndustry | StatusRecruiting | Library tests named
|
| NCT07667478 | Start2026 | PhaseNot applicable | ConditionsDementia and Alzheimer's, Mild cognitive impairment | Participants40 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07656389 | Start2026 | PhaseObservational | ConditionsMild cognitive impairment, Aging, frailty and exercise | Participants192 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07652775 | Start2026 | PhaseNot applicable | ConditionsMild cognitive impairment, Depression and bipolar disorder | Participants45 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07651787 | Start2025 | PhaseNot applicable | ConditionsDementia and Alzheimer's, Mild cognitive impairment | Participants40 | Lead sponsorOther | StatusRecruiting | Library tests named
|
Questions, answered from the data
Which cognitive test do mild cognitive impairment trials use most?
The Trail Making Test: 213 of the 859 registered studies name it in an outcome measure, 25%. Next come Verbal Learning (183) and Verbal Fluency (177).
Which cognitive test do mild cognitive impairment trials use most as a primary outcome?
Verbal Learning, named in a primary outcome by 101 studies. 508 of the 859 studies, 59%, name a cognitive test in a primary outcome.
How many participants does a phase 2 mild cognitive impairment trial enroll?
Half of the phase 2 mild cognitive impairment studies enroll 79 participants or fewer, and the middle half enroll 46 to 149. 74 of them give a size.
How long after the start do mild cognitive impairment trials measure a cognitive outcome?
Half of the primary outcomes that name a library test are measured within 13 weeks of the start, and the middle half from 8 weeks to 7 months. 693 primary outcomes give a duration.
Which cognitive tests do mild cognitive impairment trials use together?
The Digit Span Test with the Trail Making Test most often: 95 studies name both. Next, the Trail Making Test with Verbal Fluency (86).
How many completed mild cognitive impairment trials have reported results?
161 of the 365 completed mild cognitive impairment studies, 44%, have reported results: 95 posted them on ClinicalTrials.gov, 104 have a results paper linked to the registry record, and 38 did both. The other 204 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.
Plan the cognitive outcomes of a mild cognitive impairment trial
Choose tests with a record in registered trials, and run them in a browser at every site, on the same version each visit.