Clinical trials data
Cognitive tests in hearing loss trials: 247 registered studies
Every registered hearing loss 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 hearing loss studies name a cognitive test in an outcome
- 247
- Led by industry
- 93
The tests hearing loss trials use most
The Trail Making Test leads: 17 of the 247 studies name it, 7%. Next comes the Digit Span Test (14). As a primary outcome, the Trail Making Test leads with 8 studies.
- 1
Trail Making Test17 studies, 8 as a primary outcome
- 2
Digit Span Test14 studies, 7 as a primary outcome
- 3
Spectral Ripple Task9 studies, 5 as a primary outcome
- 4
Vocabulary Test9 studies, 3 as a primary outcome
- 5
Stroop Color-Word Test8 studies, 3 as a primary outcome
- 6
Symbol Coding7 studies, 4 as a primary outcome
- 7
Digits-in-Noise Task7 studies, 2 as a primary outcome
- 8
Task Switching Test7 studies, 2 as a primary outcome
- 9
Pitch Discrimination Task6 studies, 5 as a primary outcome
- 10
Reading Span Task5 studies, 3 as a primary outcome
- 11
Verbal Learning5 studies, 2 as a primary outcome
- 12
Category Fluency4 studies, 3 as a primary outcome
- 13
Short Story Recall4 studies, 3 as a primary outcome
- 14
Vocal Emotion Task4 studies, 2 as a primary outcome
- 15
Matrix Reasoning4 studies, 1 as a primary outcome
- 16
Gap Detection Task3 studies, 3 as a primary outcome
- 17
Delayed Recall Module3 studies, 2 as a primary outcome
- 18
N-Back Task3 studies, 2 as a primary outcome
- 19
Picture Naming Test3 studies, 2 as a primary outcome
- 20
Verbal Fluency3 studies, 2 as a primary outcome
- 21
Complex Figure Copy and Recall2 studies, 1 as a primary outcome
- 22
Eriksen Flanker Task2 studies, 0 as a primary outcome
- 23
Go/No-Go Task2 studies, 0 as a primary outcome
- 24
Hidden Path Learning2 studies, 0 as a primary outcome
- 25
Oddball Target Detection2 studies, 0 as a primary outcome
A test as a primary outcomeOnly in secondary or other outcomes
66% of hearing loss 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 51 tests.
Tests used together
- Digit Span Test and Trail Making Test9 studies name both
- Task Switching Test and Trail Making Test6 studies name both
- Symbol Coding and Trail Making Test5 studies name both
- Category Fluency and Short Story Recall4 studies name both
- Category Fluency and Trail Making Test4 studies name both
- Short Story Recall and Trail Making Test4 studies name both
- Category Fluency and Digit Span Test3 studies name both
- Category Fluency and Picture Naming Test3 studies name both
- Category Fluency and Symbol Coding3 studies name both
- Delayed Recall Module and Trail Making Test3 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 | 0 | 0 |
| 2003 | 0 | 0 |
| 2004 | 2 | 2 |
| 2005 | 0 | 0 |
| 2006 | 2 | 2 |
| 2007 | 1 | 0 |
| 2008 | 2 | 1 |
| 2009 | 2 | 2 |
| 2010 | 0 | 0 |
| 2011 | 1 | 0 |
| 2012 | 4 | 1 |
| 2013 | 6 | 3 |
| 2014 | 8 | 2 |
| 2015 | 7 | 2 |
| 2016 | 6 | 2 |
| 2017 | 14 | 9 |
| 2018 | 13 | 7 |
| 2019 | 17 | 11 |
| 2020 | 16 | 8 |
| 2021 | 21 | 11 |
| 2022 | 34 | 20 |
| 2023 | 23 | 15 |
| 2024 | 22 | 18 |
| 2025 | 24 | 10 |
| 2026 | 17 | 6 |
Phases and sponsors
By phase
- Early phase 11 studies, 1 as a primary outcome
- Phase 14 studies, 0 as a primary outcome
- Phase 1/25 studies, 0 as a primary outcome
- Phase 212 studies, 4 as a primary outcome
- Phase 32 studies, 2 as a primary outcome
- Phase 41 studies, 1 as a primary outcome
- Not applicable173 studies, 97 as a primary outcome
- Observational49 studies, 28 as a primary outcome
Sponsors and study types
Lead sponsor: industry 93, NIH 0, universities, hospitals and others 154. Interventional 198, observational 49.
Status, results, interventions and countries
Status
- Recruiting45 studies, 25 as a primary outcome
- Not yet recruiting15 studies, 6 as a primary outcome
- Active, not recruiting8 studies, 6 as a primary outcome
- Completed126 studies, 70 as a primary outcome
- Stopped early20 studies, 9 as a primary outcome
- Status unknown33 studies, 17 as a primary outcome
What they test
- Behavioral45 studies, 32 as a primary outcome
- Drug25 studies, 5 as a primary outcome
- Device123 studies, 61 as a primary outcome
- Dietary supplement1 studies, 1 as a primary outcome
- Procedure4 studies, 1 as a primary outcome
- Diagnostic test17 studies, 8 as a primary outcome
- Genetic2 studies, 1 as a primary outcome
- Other41 studies, 23 as a primary outcome
- None given12 studies, 11 as a primary outcome
Intervention types as registered. A study can list several; observational studies often list none.
Where their sites are
- United States114 studies, 69 as a primary outcome
- France21 studies, 7 as a primary outcome
- Canada19 studies, 12 as a primary outcome
- United Kingdom13 studies, 5 as a primary outcome
- Belgium12 studies, 4 as a primary outcome
- Germany12 studies, 9 as a primary outcome
- Switzerland11 studies, 3 as a primary outcome
- China8 studies, 5 as a primary outcome
- Australia7 studies, 4 as a primary outcome
- Denmark7 studies, 3 as a primary outcome
- Netherlands6 studies, 3 as a primary outcome
- Finland3 studies, 2 as a primary outcome
26 countries in all. A study with sites in several counts in each; 19 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 hearing loss studies: 71 of 126, 56%
Every completed study with a cognitive outcome: 3,626 of 7,953, 46%
| Results | Completed hearing loss studies | Every completed study |
|---|---|---|
| Results on ClinicalTrials.gov and a paper | 13, 10% | 776, 10% |
| Results on ClinicalTrials.gov only | 44, 35% | 1,139, 14% |
| A results paper only | 14, 11% | 1,711, 22% |
| Neither | 55, 44% | 4,327, 54% |
How many participants they enroll
- Phase 278 median, 32 to 113
- Not applicable40 median, 20 to 76
- Observational80 median, 42 to 181
Show as a table
| Phase | Studies with a size | Median | Middle half |
|---|---|---|---|
| Phase 2 | 11 | 78 | 32 to 113 |
| Not applicable | 169 | 40 | 20 to 76 |
| Observational | 47 | 80 | 42 to 181 |
When the cognitive outcome is measured
Latest time point of each outcome
- Within a day24 outcomes, 9 as a primary outcome
- Up to 4 weeks19 outcomes, 3 as a primary outcome
- 1 to 3 months29 outcomes, 12 as a primary outcome
- 3 to 6 months23 outcomes, 9 as a primary outcome
- 6 to 12 months15 outcomes, 10 as a primary outcome
- 1 to 2 years5 outcomes, 2 as a primary outcome
- Over 2 years29 outcomes, 24 as a primary outcome
- No duration given17 outcomes, 13 as a primary outcome
A test as a primary outcomeOnly in secondary or other outcomes
144 of the 161 outcome measures give a duration. A single visit counts as within a day.
Explore the hearing loss studies
84 studies match. 39 name a library test in a primary outcome. Median size 57 participants. Median time to the primary outcome: 12 months.
Loading 84 studies; the filters turn on when they arrive.
2026 is partly planned starts. Not shown: 2 planned to start after 2026.
Show as a table
| Start year | Studies | As a primary outcome |
|---|---|---|
| 2000 | 0 | 0 |
| 2001 | 0 | 0 |
| 2002 | 0 | 0 |
| 2003 | 0 | 0 |
| 2004 | 0 | 0 |
| 2005 | 0 | 0 |
| 2006 | 0 | 0 |
| 2007 | 1 | 0 |
| 2008 | 1 | 1 |
| 2009 | 0 | 0 |
| 2010 | 0 | 0 |
| 2011 | 0 | 0 |
| 2012 | 2 | 1 |
| 2013 | 0 | 0 |
| 2014 | 3 | 0 |
| 2015 | 3 | 1 |
| 2016 | 4 | 1 |
| 2017 | 4 | 2 |
| 2018 | 6 | 3 |
| 2019 | 6 | 2 |
| 2020 | 7 | 4 |
| 2021 | 8 | 5 |
| 2022 | 9 | 5 |
| 2023 | 9 | 6 |
| 2024 | 6 | 3 |
| 2025 | 8 | 2 |
| 2026 | 5 | 2 |
Library tests named most
Largest condition groups
Phases
Participants
Lead sponsor: industry 13, other 71. Interventional 65, observational 19.
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 |
|---|---|---|---|---|---|---|---|
| NCT07869745 | Start2027 | PhaseNot applicable | ConditionsHearing loss | Participants76 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07782567 | Start2026 | PhaseNot applicable | ConditionsHearing loss | Participants30 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07646119 | Start2026 | PhaseObservational | ConditionsHearing loss | Participants200 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07584837 | Start2027 | PhaseObservational | ConditionsHearing loss | Participants40 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07509788 | Start2025 | PhaseObservational | ConditionsHearing loss | Participants360 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07506408 | Start2026 | PhaseNot applicable | ConditionsHearing loss | Participants120 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07447427 | Start2026 | PhaseObservational | ConditionsHearing loss | Participants60 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT07297524 | Start2025 | PhaseNot applicable | ConditionsHearing loss | Participants25 | Lead sponsorOther | StatusNot yet recruiting | Library tests named
|
| NCT07035873 | Start2025 | PhaseNot applicable | ConditionsHearing loss | Participants15 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT06955494 | Start2025 | PhaseNot applicable | ConditionsMild cognitive impairment, Hearing loss | Participants62 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT06951815 | Start2025 | PhaseNot applicable | ConditionsHearing loss, Pain and fatigue | Participants60 | Lead sponsorOther | StatusCompleted | Library tests named
|
| NCT06930170 | Start2026 | PhaseNot applicable | ConditionsHearing loss | Participants36 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT06902753 | Start2025 | PhaseNot applicable | ConditionsDementia and Alzheimer's, Hearing loss | Participants120 | Lead sponsorOther | StatusStopped early | Library tests named
|
| NCT06580847 | Start2025 | PhaseNot applicable | ConditionsHearing loss | Participants210 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT06495268 | Start2024 | PhaseNot applicable | ConditionsHearing loss | Participants200 | Lead sponsorOther | StatusActive, not recruiting | Library tests named
|
| NCT06486285 | Start2024 | PhaseNot applicable | ConditionsHearing loss | Participants60 | Lead sponsorOther | StatusCompleted | Library tests named
|
| NCT06477354 | Start2024 | PhaseNot applicable | ConditionsHearing loss | Participants64 | Lead sponsorOther | StatusCompleted | Library tests named
|
| NCT06309264 | Start2024 | PhaseNot applicable | ConditionsHearing loss | Participants80 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT06174038 | Start2024 | PhaseNot applicable | ConditionsDementia and Alzheimer's, Hearing loss | Participants150 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT06133946 | Start2016 | PhaseObservational | ConditionsHearing loss | Participants35,920 | Lead sponsorOther | StatusActive, not recruiting | Library tests named
|
| NCT06053190 | Start2023 | PhaseNot applicable | ConditionsHearing loss | Participants80 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT05962359 | Start2023 | PhaseNot applicable | ConditionsHearing loss | Participants700 | Lead sponsorOther | StatusRecruiting | Library tests named
|
| NCT05950412 | Start2023 | PhaseObservational | ConditionsHearing loss | Participants37 | Lead sponsorOther | StatusStatus unknown | Library tests named
|
| NCT05848661 | Start2024 | PhaseNot applicable | ConditionsHearing loss | Participants240 | Lead sponsorIndustry | StatusStatus unknown | Library tests named
|
| NCT05782153 | Start2023 | PhaseNot applicable | ConditionsHearing loss | Participants40 | Lead sponsorIndustry | StatusCompleted | Library tests named
|
Questions, answered from the data
Which cognitive test do hearing loss trials use most?
The Trail Making Test: 17 of the 247 registered studies name it in an outcome measure, 7%. Next come the Digit Span Test (14) and the Spectral Ripple Task (9).
Which cognitive test do hearing loss trials use most as a primary outcome?
The Trail Making Test, named in a primary outcome by 8 studies. 133 of the 247 studies, 54%, name a cognitive test in a primary outcome.
How many participants does a phase 2 hearing loss trial enroll?
Half of the phase 2 hearing loss studies enroll 78 participants or fewer, and the middle half enroll 32 to 113. 11 of them give a size.
How long after the start do hearing loss trials measure a cognitive outcome?
Half of the primary outcomes that name a library test are measured within 12 months of the start, and the middle half from 9 weeks to 3 years. 69 primary outcomes give a duration.
Which cognitive tests do hearing loss trials use together?
The Digit Span Test with the Trail Making Test most often: 9 studies name both. Next, the Task Switching Test with the Trail Making Test (6).
How many completed hearing loss trials have reported results?
71 of the 126 completed hearing loss studies, 56%, have reported results: 57 posted them on ClinicalTrials.gov, 27 have a results paper linked to the registry record, and 13 did both. The other 55 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 hearing loss trial
Choose tests with a record in registered trials, and run them in a browser at every site, on the same version each visit.