Clinical trials data

Digit Span Test in dementia and Alzheimer's trials: 181 registered studies

Every registered dementia and Alzheimer's disease study on ClinicalTrials.gov that names the Digit Span 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 dementia and Alzheimer's disease studies name it in an outcome measure: 181
Name it in a primary outcome, 34%: 61 of 181
Of the condition's 1,673 studies name it, against 10% of all registered studies: 11%; Other conditions
Median participants per study: 70; By phase

Try the Digit Span Test

Tests named in the same studies

The library tests that dementia and Alzheimer's disease studies naming the Digit Span Test name most often beside it.

1
Trail Making Test104 studies, 35 as a primary outcome
2
Verbal Learning79 studies, 34 as a primary outcome
3
Verbal Fluency76 studies, 24 as a primary outcome
4
Category Fluency65 studies, 19 as a primary outcome
5
Picture Naming Test44 studies, 14 as a primary outcome
6
Stroop Color-Word Test39 studies, 17 as a primary outcome
7
Short Story Recall37 studies, 16 as a primary outcome
8
Symbol Coding36 studies, 16 as a primary outcome
9
Complex Figure Copy and Recall27 studies, 12 as a primary outcome
10
Clock Drawing Task20 studies, 8 as a primary outcome

A test as a primary outcomeOnly in secondary or other outcomes

Studies by start year

Each study counted once. 2026 is partly planned starts.

A test as a primary outcomeOnly in secondary or other outcomes

Show as a table

Registered studies by start year
Start year	Studies	A test as a primary outcome
2000	0	0
2001	0	0
2002	0	0
2003	1	1
2004	0	0
2005	1	0
2006	0	0
2007	1	0
2008	4	2
2009	3	1
2010	8	3
2011	4	3
2012	5	2
2013	4	1
2014	5	3
2015	10	3
2016	5	1
2017	10	2
2018	8	1
2019	16	5
2020	7	2
2021	14	6
2022	12	4
2023	18	5
2024	16	8
2025	17	3
2026	10	4

Phases and study sizes

By phase

Early phase 11 studies, 0 as a primary outcome
Phase 13 studies, 0 as a primary outcome
Phase 1/27 studies, 1 as a primary outcome
Phase 223 studies, 7 as a primary outcome
Phase 2/34 studies, 0 as a primary outcome
Phase 38 studies, 3 as a primary outcome
Phase 44 studies, 0 as a primary outcome
Not applicable106 studies, 36 as a primary outcome
Observational25 studies, 14 as a primary outcome

Participants per study

Phase 257 median, 33 to 172
Not applicable60 median, 40 to 137
Observational165 median, 79 to 884

Participants per study. The bar spans the middle half of the studies in each phase, the mark is the median, and the axis is logarithmic. Phases with fewer than 10 studies that give a size are left out.

Show as a table

Participants per dementia and Alzheimer's disease study that names the Digit Span Test, by phase
Phase	Studies with a size	Median	Middle half
Phase 2	22	57	33 to 172
Not applicable	106	60	40 to 137
Observational	24	165	79 to 884

When dementia and Alzheimer's trials measure it

Half of the primary outcomes that name the Digit Span Test are measured within 6 months of the start, and the middle half from 9 weeks to 2 years. 55 primary outcomes give a duration.

Latest time point of each outcome

Within a day10 outcomes, 6 as a primary outcome
Up to 4 weeks16 outcomes, 5 as a primary outcome
1 to 3 months34 outcomes, 10 as a primary outcome
3 to 6 months36 outcomes, 11 as a primary outcome
6 to 12 months35 outcomes, 6 as a primary outcome
1 to 2 years24 outcomes, 6 as a primary outcome
Over 2 years18 outcomes, 11 as a primary outcome
No duration given8 outcomes, 6 as a primary outcome

A test as a primary outcomeOnly in secondary or other outcomes

173 of the 181 outcome measures give a duration. A single visit counts as within a day.

Status, results, interventions and countries

Status

Recruiting30 studies, 12 as a primary outcome
Not yet recruiting12 studies, 4 as a primary outcome
Active, not recruiting9 studies, 4 as a primary outcome
Completed87 studies, 30 as a primary outcome
Stopped early16 studies, 5 as a primary outcome
Status unknown27 studies, 6 as a primary outcome

What they test

Behavioral51 studies, 22 as a primary outcome
Drug35 studies, 7 as a primary outcome
Device41 studies, 11 as a primary outcome
Dietary supplement7 studies, 0 as a primary outcome
Procedure7 studies, 3 as a primary outcome
Diagnostic test5 studies, 0 as a primary outcome
Biological7 studies, 1 as a primary outcome
Radiation1 studies, 1 as a primary outcome
Combination product1 studies, 1 as a primary outcome
Genetic1 studies, 1 as a primary outcome
Other40 studies, 15 as a primary outcome
None given12 studies, 9 as a primary outcome

Intervention types as registered. A study can list several; observational studies often list none.

54 countries in all. A study with sites in several counts in each; 15 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 dementia and Alzheimer's disease studies that name the Digit Span Test: 52 of 87, 60%

Every completed study with a cognitive outcome: 3,626 of 7,953, 46%

Completed dementia and Alzheimer's disease studies that name the Digit Span Test and every completed study, by how they reported results
Results	Completed dementia and Alzheimer's disease studies that name the Digit Span Test	Every completed study
Results on ClinicalTrials.gov and a paper	15, 17%	776, 10%
Results on ClinicalTrials.gov only	9, 10%	1,139, 14%
A results paper only	28, 32%	1,711, 22%
Neither	35, 40%	4,327, 54%

The 181 studies

Filter by phase, sponsor, status, country, intervention, outcome list, size and start year. Each study links to its record on ClinicalTrials.gov.

181 studies match. 61 name the Digit Span Test in a primary outcome. Median size 70 participants. Median time to the primary outcome: 6 months.

Loading 181 studies; the filters turn on when they arrive.

By start year

2026 is partly planned starts. Not shown: 1 that started before 2000 and 1 planned to start after 2026.

Show as a table

Matching studies by start year
Start year	Studies	As a primary outcome
2000	0	0
2001	0	0
2002	0	0
2003	1	1
2004	0	0
2005	1	0
2006	0	0
2007	1	0
2008	4	2
2009	3	1
2010	8	3
2011	4	3
2012	5	2
2013	4	1
2014	5	3
2015	10	3
2016	5	1
2017	10	2
2018	8	1
2019	16	5
2020	7	2
2021	14	6
2022	12	4
2023	18	5
2024	16	8
2025	17	3
2026	10	4

Library tests named most

Largest condition groups

Dementia and Alzheimer's181 studies, 61 as a primary outcome
Mild cognitive impairment49 studies, 20 as a primary outcome
Aging, frailty and exercise15 studies, 6 as a primary outcome
Parkinson's disease6 studies, 3 as a primary outcome
Healthy volunteers6 studies, 5 as a primary outcome
Depression and bipolar disorder5 studies, 2 as a primary outcome
Obesity and diabetes4 studies, 2 as a primary outcome
Delirium, surgery and intensive care4 studies, 1 as a primary outcome
Sleep and sleep disorders3 studies, 2 as a primary outcome
Stroke2 studies, 1 as a primary outcome
Hearing loss2 studies, 2 as a primary outcome
Schizophrenia and psychosis1 study, 0 as a primary outcome

Phases

Participants

Lead sponsor: industry 30, other 151. Interventional 156, observational 25.

As a primary outcomeSecondary or other outcomeThe Digit Span Test

The studies, newest registration first

Each number opens the study's record on ClinicalTrials.gov.

Registered studies that match the filters, newest registration first, with the library tests each one names and the outcome list that names them.
Study	Start	Phase	Conditions	Participants	Lead sponsor	Status	Library tests named, with the latest time point
NCT07883148	Start2024	PhaseNot applicable	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants52	Lead sponsorOther	StatusCompleted	Library tests named Trail Making TestSecondary8 months Verbal LearningSecondary8 months Verbal FluencySecondary8 months Digit Span TestSecondary8 months Complex Figure Copy and RecallSecondary8 months
NCT07882251	Start2021	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants80	Lead sponsorOther	StatusCompleted	Library tests named Stroop Color-Word TestPrimary5 weeks Verbal LearningPrimary5 weeks Digit Span TestPrimary5 weeks Category FluencyPrimary5 weeks Complex Figure Copy and RecallPrimary5 weeks Corsi Block-Tapping TestPrimary5 weeks Line Angle MatchingPrimary5 weeks
NCT07779863	Start2027	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants188	Lead sponsorOther	StatusNot yet recruiting	Library tests named Digit Span TestSecondary12 months
NCT07766993	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants100	Lead sponsorOther	StatusNot yet recruiting	Library tests named Digit Span TestPrimary12 months
NCT07731334	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants384	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestSecondary12 months Stroop Color-Word TestSecondary12 months Verbal LearningSecondary12 months Verbal FluencySecondary12 months Digit Span TestSecondary12 months Complex Figure Copy and RecallSecondary12 months Corsi Block-Tapping TestSecondary12 months Oddball Target DetectionSecondary
NCT07722169	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants48	Lead sponsorOther	StatusNot yet recruiting	Library tests named Verbal FluencySecondary13 weeks Digit Span TestSecondary13 weeks Category FluencySecondary13 weeks Picture Naming TestSecondary13 weeks Matrix ReasoningSecondary13 weeks Token Commands TaskSecondary13 weeks
NCT07673770	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants30	Lead sponsorOther	StatusRecruiting	Library tests named Digit Span TestPrimary4 months
NCT07672977	Start2025	PhaseNot applicable	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants30	Lead sponsorIndustry	StatusRecruiting	Library tests named Verbal LearningOther outcome7 months Digit Span TestOther outcome7 months Short Story RecallOther outcome7 months Symbol Scan TaskOther outcome7 months Word Pair LearningOther outcome7 months
NCT07667478	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants40	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestPrimary6 months Verbal LearningPrimary6 months Digit Span TestPrimary6 months Picture Naming TestPrimary6 months
NCT07629349	Start2020	PhaseObservational	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants600	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestPrimary6 months Verbal LearningPrimary6 months Digit Span TestPrimary6 months Complex Figure Copy and RecallPrimary6 months Matrix ReasoningPrimary6 months Block Copy TestPrimary6 months
NCT07618481	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants90	Lead sponsorOther	StatusRecruiting	Library tests named Verbal LearningSecondary6 months Digit Span TestSecondary6 months Task Switching TestSecondary6 months
NCT07543094	Start2025	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants40	Lead sponsorOther	StatusRecruiting	Library tests named Digit Span TestSecondary12 weeks Task Switching TestSecondary12 weeks
NCT07505784	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants30	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestPrimary Verbal FluencyPrimary Digit Span TestPrimary Go/No-Go TaskPrimary Category FluencyPrimary Task Switching TestPrimary Emoji Emotion RecognitionPrimary
NCT07399418	Start2025	PhaseObservational	ConditionsDementia and Alzheimer's	Participants80	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestPrimarysame day Stroop Color-Word TestPrimarysame day Verbal FluencyPrimarysame day Digit Span TestPrimarysame day Go/No-Go TaskPrimarysame day Category FluencyPrimarysame day Clock Drawing TaskPrimarysame day Complex Figure Copy and RecallPrimarysame day Matrix ReasoningPrimarysame day Selective Reminding TaskPrimarysame day
NCT07392723	Start2025	PhasePhase 2	ConditionsDementia and Alzheimer's, Aging, frailty and exercise	Participants20	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestSecondary6 months Digit Span TestSecondary6 months Category FluencySecondary6 months Delayed Recall ModuleSecondary6 months
NCT07385937	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants150	Lead sponsorOther	StatusNot yet recruiting	Library tests named Trail Making TestSecondary18 months Verbal FluencySecondary18 months Digit Span TestSecondary18 months Category FluencySecondary18 months Clock Drawing TaskSecondary18 months Cancellation TestSecondary18 months Delayed Recall ModuleSecondary18 months
NCT07376135	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants300	Lead sponsorOther	StatusNot yet recruiting	Library tests named Trail Making TestOther outcome18 months Stroop Color-Word TestOther outcome18 months Verbal LearningOther outcome18 months Digit Span TestOther outcome18 months Symbol CodingOther outcome18 months Short Story RecallOther outcome18 months Complex Figure Copy and RecallOther outcome18 months
NCT07375771	Start2025	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants40	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestPrimary12 weeks Verbal LearningPrimary12 weeks Verbal FluencyPrimary12 weeks Digit Span TestPrimary12 weeks Category FluencyPrimary12 weeks Task Switching TestPrimary12 weeks Clock Drawing TaskPrimary12 weeks Complex Figure Copy and RecallPrimary12 weeks Visual Search TestPrimary12 weeks
NCT07241598	Start2025	PhaseNot applicable	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants70	Lead sponsorOther	StatusNot yet recruiting	Library tests named Trail Making TestSecondary12 months Verbal FluencySecondary12 months Digit Span TestSecondary12 months Symbol CodingSecondary12 months Go/No-Go TaskSecondary12 months Category FluencySecondary12 months
NCT07230158	Start2025	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants160	Lead sponsorOther	StatusNot yet recruiting	Library tests named Trail Making TestSecondary8 weeks Verbal LearningSecondary8 weeks Digit Span TestSecondary8 weeks Picture Naming TestSecondary8 weeks
NCT07210528	Start2025	PhasePhase 1	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants48	Lead sponsorOther	StatusActive, not recruiting	Library tests named Digit Span TestSecondary12 weeks Category FluencySecondary12 weeks Picture Naming TestSecondary12 weeks Short Story RecallSecondary12 weeks
NCT07109999	Start2019	PhaseObservational	ConditionsDementia and Alzheimer's	Participants2,835	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestSecondary15 years Digit Span TestSecondary15 years Picture Naming TestSecondary15 years
NCT07089303	Start2025	PhaseObservational	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants750	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestSecondary12 months Stroop Color-Word TestSecondary12 months Verbal LearningSecondary12 months Digit Span TestSecondary12 months Symbol CodingSecondary12 months Picture Naming TestSecondary12 months Clock Drawing TaskSecondary12 months Complex Figure Copy and RecallSecondary12 months
NCT07087951	Start2025	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants70	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestSecondary13 weeks Verbal LearningSecondary13 weeks Verbal FluencySecondary13 weeks Digit Span TestSecondary13 weeks Short Story RecallSecondary13 weeks Complex Figure Copy and RecallSecondary13 weeks
NCT07064382	Start2025	PhaseNot applicable	ConditionsDementia and Alzheimer's, Sleep and sleep disorders	Participants60	Lead sponsorOther	StatusNot yet recruiting	Library tests named Digit Span TestPrimary3 years Mental RotationPrimary3 years Route Directions Task and Which-Way-Back GamePrimary3 years

Questions, answered from the data

How many dementia and Alzheimer's trials use the Digit Span Test?

181 registered dementia and Alzheimer's disease studies on ClinicalTrials.gov name it in an outcome measure, 61 of them in a primary outcome: 11% of the condition's 1,673 studies with a cognitive outcome, against 10% of all of them. It is the 4th most named test in dementia and Alzheimer's trials.

Which tests do dementia and Alzheimer's trials use with the Digit Span Test?

The Trail Making Test (104 studies), Verbal Learning (79 studies) and Verbal Fluency (76 studies).

How many participants do phase 2 dementia and Alzheimer's trials that use the Digit Span Test enroll?

Half of the phase 2 studies that name it enroll 57 participants or fewer, and the middle half enroll 33 to 172. 22 of them give a size.

When do dementia and Alzheimer's trials measure the Digit Span Test?

Half of the primary outcomes that name the Digit Span Test are measured within 6 months of the start, and the middle half from 9 weeks to 2 years. 55 primary outcomes give a duration.

How many completed dementia and Alzheimer's trials that use the Digit Span Test have reported results?

52 of the 87 completed studies that name it, 60%, have reported results: 24 posted them on ClinicalTrials.gov, 43 have a results paper linked to the registry record, and 15 did both. The other 35 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.

Run the Digit Span Test in your trial

Choose tests with a record in registered trials, and run them in a browser at every site, on the same version each visit.

Start free

Clinical trials data

Digit Span Test in dementia and Alzheimer's trials: 181 registered studies

Registered dementia and Alzheimer's disease studies name it in an outcome measure: 181
Name it in a primary outcome, 34%: 61 of 181
Of the condition's 1,673 studies name it, against 10% of all registered studies: 11%; Other conditions
Median participants per study: 70; By phase

Try the Digit Span Test

Tests named in the same studies

The library tests that dementia and Alzheimer's disease studies naming the Digit Span Test name most often beside it.

1
Trail Making Test104 studies, 35 as a primary outcome
2
Verbal Learning79 studies, 34 as a primary outcome
3
Verbal Fluency76 studies, 24 as a primary outcome
4
Category Fluency65 studies, 19 as a primary outcome
5
Picture Naming Test44 studies, 14 as a primary outcome
6
Stroop Color-Word Test39 studies, 17 as a primary outcome
7
Short Story Recall37 studies, 16 as a primary outcome
8
Symbol Coding36 studies, 16 as a primary outcome
9
Complex Figure Copy and Recall27 studies, 12 as a primary outcome
10
Clock Drawing Task20 studies, 8 as a primary outcome

A test as a primary outcomeOnly in secondary or other outcomes

Studies by start year

Each study counted once. 2026 is partly planned starts.

A test as a primary outcomeOnly in secondary or other outcomes

Show as a table

Registered studies by start year
Start year	Studies	A test as a primary outcome
2000	0	0
2001	0	0
2002	0	0
2003	1	1
2004	0	0
2005	1	0
2006	0	0
2007	1	0
2008	4	2
2009	3	1
2010	8	3
2011	4	3
2012	5	2
2013	4	1
2014	5	3
2015	10	3
2016	5	1
2017	10	2
2018	8	1
2019	16	5
2020	7	2
2021	14	6
2022	12	4
2023	18	5
2024	16	8
2025	17	3
2026	10	4

Phases and study sizes

By phase

Early phase 11 studies, 0 as a primary outcome
Phase 13 studies, 0 as a primary outcome
Phase 1/27 studies, 1 as a primary outcome
Phase 223 studies, 7 as a primary outcome
Phase 2/34 studies, 0 as a primary outcome
Phase 38 studies, 3 as a primary outcome
Phase 44 studies, 0 as a primary outcome
Not applicable106 studies, 36 as a primary outcome
Observational25 studies, 14 as a primary outcome

Participants per study

Phase 257 median, 33 to 172
Not applicable60 median, 40 to 137
Observational165 median, 79 to 884

Show as a table

Participants per dementia and Alzheimer's disease study that names the Digit Span Test, by phase
Phase	Studies with a size	Median	Middle half
Phase 2	22	57	33 to 172
Not applicable	106	60	40 to 137
Observational	24	165	79 to 884

When dementia and Alzheimer's trials measure it

Half of the primary outcomes that name the Digit Span Test are measured within 6 months of the start, and the middle half from 9 weeks to 2 years. 55 primary outcomes give a duration.

Latest time point of each outcome

Within a day10 outcomes, 6 as a primary outcome
Up to 4 weeks16 outcomes, 5 as a primary outcome
1 to 3 months34 outcomes, 10 as a primary outcome
3 to 6 months36 outcomes, 11 as a primary outcome
6 to 12 months35 outcomes, 6 as a primary outcome
1 to 2 years24 outcomes, 6 as a primary outcome
Over 2 years18 outcomes, 11 as a primary outcome
No duration given8 outcomes, 6 as a primary outcome

A test as a primary outcomeOnly in secondary or other outcomes

173 of the 181 outcome measures give a duration. A single visit counts as within a day.

Status, results, interventions and countries

Status

Recruiting30 studies, 12 as a primary outcome
Not yet recruiting12 studies, 4 as a primary outcome
Active, not recruiting9 studies, 4 as a primary outcome
Completed87 studies, 30 as a primary outcome
Stopped early16 studies, 5 as a primary outcome
Status unknown27 studies, 6 as a primary outcome

What they test

Behavioral51 studies, 22 as a primary outcome
Drug35 studies, 7 as a primary outcome
Device41 studies, 11 as a primary outcome
Dietary supplement7 studies, 0 as a primary outcome
Procedure7 studies, 3 as a primary outcome
Diagnostic test5 studies, 0 as a primary outcome
Biological7 studies, 1 as a primary outcome
Radiation1 studies, 1 as a primary outcome
Combination product1 studies, 1 as a primary outcome
Genetic1 studies, 1 as a primary outcome
Other40 studies, 15 as a primary outcome
None given12 studies, 9 as a primary outcome

Intervention types as registered. A study can list several; observational studies often list none.

54 countries in all. A study with sites in several counts in each; 15 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 dementia and Alzheimer's disease studies that name the Digit Span Test: 52 of 87, 60%

Every completed study with a cognitive outcome: 3,626 of 7,953, 46%

Completed dementia and Alzheimer's disease studies that name the Digit Span Test and every completed study, by how they reported results
Results	Completed dementia and Alzheimer's disease studies that name the Digit Span Test	Every completed study
Results on ClinicalTrials.gov and a paper	15, 17%	776, 10%
Results on ClinicalTrials.gov only	9, 10%	1,139, 14%
A results paper only	28, 32%	1,711, 22%
Neither	35, 40%	4,327, 54%

The 181 studies

Filter by phase, sponsor, status, country, intervention, outcome list, size and start year. Each study links to its record on ClinicalTrials.gov.

181 studies match. 61 name the Digit Span Test in a primary outcome. Median size 70 participants. Median time to the primary outcome: 6 months.

Loading 181 studies; the filters turn on when they arrive.

By start year

2026 is partly planned starts. Not shown: 1 that started before 2000 and 1 planned to start after 2026.

Show as a table

Matching studies by start year
Start year	Studies	As a primary outcome
2000	0	0
2001	0	0
2002	0	0
2003	1	1
2004	0	0
2005	1	0
2006	0	0
2007	1	0
2008	4	2
2009	3	1
2010	8	3
2011	4	3
2012	5	2
2013	4	1
2014	5	3
2015	10	3
2016	5	1
2017	10	2
2018	8	1
2019	16	5
2020	7	2
2021	14	6
2022	12	4
2023	18	5
2024	16	8
2025	17	3
2026	10	4

Library tests named most

Largest condition groups

Dementia and Alzheimer's181 studies, 61 as a primary outcome
Mild cognitive impairment49 studies, 20 as a primary outcome
Aging, frailty and exercise15 studies, 6 as a primary outcome
Parkinson's disease6 studies, 3 as a primary outcome
Healthy volunteers6 studies, 5 as a primary outcome
Depression and bipolar disorder5 studies, 2 as a primary outcome
Obesity and diabetes4 studies, 2 as a primary outcome
Delirium, surgery and intensive care4 studies, 1 as a primary outcome
Sleep and sleep disorders3 studies, 2 as a primary outcome
Stroke2 studies, 1 as a primary outcome
Hearing loss2 studies, 2 as a primary outcome
Schizophrenia and psychosis1 study, 0 as a primary outcome

Phases

Participants

Lead sponsor: industry 30, other 151. Interventional 156, observational 25.

As a primary outcomeSecondary or other outcomeThe Digit Span Test

The studies, newest registration first

Each number opens the study's record on ClinicalTrials.gov.

Registered studies that match the filters, newest registration first, with the library tests each one names and the outcome list that names them.
Study	Start	Phase	Conditions	Participants	Lead sponsor	Status	Library tests named, with the latest time point
NCT07883148	Start2024	PhaseNot applicable	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants52	Lead sponsorOther	StatusCompleted	Library tests named Trail Making TestSecondary8 months Verbal LearningSecondary8 months Verbal FluencySecondary8 months Digit Span TestSecondary8 months Complex Figure Copy and RecallSecondary8 months
NCT07882251	Start2021	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants80	Lead sponsorOther	StatusCompleted	Library tests named Stroop Color-Word TestPrimary5 weeks Verbal LearningPrimary5 weeks Digit Span TestPrimary5 weeks Category FluencyPrimary5 weeks Complex Figure Copy and RecallPrimary5 weeks Corsi Block-Tapping TestPrimary5 weeks Line Angle MatchingPrimary5 weeks
NCT07779863	Start2027	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants188	Lead sponsorOther	StatusNot yet recruiting	Library tests named Digit Span TestSecondary12 months
NCT07766993	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants100	Lead sponsorOther	StatusNot yet recruiting	Library tests named Digit Span TestPrimary12 months
NCT07731334	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants384	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestSecondary12 months Stroop Color-Word TestSecondary12 months Verbal LearningSecondary12 months Verbal FluencySecondary12 months Digit Span TestSecondary12 months Complex Figure Copy and RecallSecondary12 months Corsi Block-Tapping TestSecondary12 months Oddball Target DetectionSecondary
NCT07722169	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants48	Lead sponsorOther	StatusNot yet recruiting	Library tests named Verbal FluencySecondary13 weeks Digit Span TestSecondary13 weeks Category FluencySecondary13 weeks Picture Naming TestSecondary13 weeks Matrix ReasoningSecondary13 weeks Token Commands TaskSecondary13 weeks
NCT07673770	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants30	Lead sponsorOther	StatusRecruiting	Library tests named Digit Span TestPrimary4 months
NCT07672977	Start2025	PhaseNot applicable	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants30	Lead sponsorIndustry	StatusRecruiting	Library tests named Verbal LearningOther outcome7 months Digit Span TestOther outcome7 months Short Story RecallOther outcome7 months Symbol Scan TaskOther outcome7 months Word Pair LearningOther outcome7 months
NCT07667478	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants40	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestPrimary6 months Verbal LearningPrimary6 months Digit Span TestPrimary6 months Picture Naming TestPrimary6 months
NCT07629349	Start2020	PhaseObservational	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants600	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestPrimary6 months Verbal LearningPrimary6 months Digit Span TestPrimary6 months Complex Figure Copy and RecallPrimary6 months Matrix ReasoningPrimary6 months Block Copy TestPrimary6 months
NCT07618481	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants90	Lead sponsorOther	StatusRecruiting	Library tests named Verbal LearningSecondary6 months Digit Span TestSecondary6 months Task Switching TestSecondary6 months
NCT07543094	Start2025	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants40	Lead sponsorOther	StatusRecruiting	Library tests named Digit Span TestSecondary12 weeks Task Switching TestSecondary12 weeks
NCT07505784	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants30	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestPrimary Verbal FluencyPrimary Digit Span TestPrimary Go/No-Go TaskPrimary Category FluencyPrimary Task Switching TestPrimary Emoji Emotion RecognitionPrimary
NCT07399418	Start2025	PhaseObservational	ConditionsDementia and Alzheimer's	Participants80	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestPrimarysame day Stroop Color-Word TestPrimarysame day Verbal FluencyPrimarysame day Digit Span TestPrimarysame day Go/No-Go TaskPrimarysame day Category FluencyPrimarysame day Clock Drawing TaskPrimarysame day Complex Figure Copy and RecallPrimarysame day Matrix ReasoningPrimarysame day Selective Reminding TaskPrimarysame day
NCT07392723	Start2025	PhasePhase 2	ConditionsDementia and Alzheimer's, Aging, frailty and exercise	Participants20	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestSecondary6 months Digit Span TestSecondary6 months Category FluencySecondary6 months Delayed Recall ModuleSecondary6 months
NCT07385937	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants150	Lead sponsorOther	StatusNot yet recruiting	Library tests named Trail Making TestSecondary18 months Verbal FluencySecondary18 months Digit Span TestSecondary18 months Category FluencySecondary18 months Clock Drawing TaskSecondary18 months Cancellation TestSecondary18 months Delayed Recall ModuleSecondary18 months
NCT07376135	Start2026	PhaseNot applicable	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants300	Lead sponsorOther	StatusNot yet recruiting	Library tests named Trail Making TestOther outcome18 months Stroop Color-Word TestOther outcome18 months Verbal LearningOther outcome18 months Digit Span TestOther outcome18 months Symbol CodingOther outcome18 months Short Story RecallOther outcome18 months Complex Figure Copy and RecallOther outcome18 months
NCT07375771	Start2025	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants40	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestPrimary12 weeks Verbal LearningPrimary12 weeks Verbal FluencyPrimary12 weeks Digit Span TestPrimary12 weeks Category FluencyPrimary12 weeks Task Switching TestPrimary12 weeks Clock Drawing TaskPrimary12 weeks Complex Figure Copy and RecallPrimary12 weeks Visual Search TestPrimary12 weeks
NCT07241598	Start2025	PhaseNot applicable	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants70	Lead sponsorOther	StatusNot yet recruiting	Library tests named Trail Making TestSecondary12 months Verbal FluencySecondary12 months Digit Span TestSecondary12 months Symbol CodingSecondary12 months Go/No-Go TaskSecondary12 months Category FluencySecondary12 months
NCT07230158	Start2025	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants160	Lead sponsorOther	StatusNot yet recruiting	Library tests named Trail Making TestSecondary8 weeks Verbal LearningSecondary8 weeks Digit Span TestSecondary8 weeks Picture Naming TestSecondary8 weeks
NCT07210528	Start2025	PhasePhase 1	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants48	Lead sponsorOther	StatusActive, not recruiting	Library tests named Digit Span TestSecondary12 weeks Category FluencySecondary12 weeks Picture Naming TestSecondary12 weeks Short Story RecallSecondary12 weeks
NCT07109999	Start2019	PhaseObservational	ConditionsDementia and Alzheimer's	Participants2,835	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestSecondary15 years Digit Span TestSecondary15 years Picture Naming TestSecondary15 years
NCT07089303	Start2025	PhaseObservational	ConditionsDementia and Alzheimer's, Mild cognitive impairment	Participants750	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestSecondary12 months Stroop Color-Word TestSecondary12 months Verbal LearningSecondary12 months Digit Span TestSecondary12 months Symbol CodingSecondary12 months Picture Naming TestSecondary12 months Clock Drawing TaskSecondary12 months Complex Figure Copy and RecallSecondary12 months
NCT07087951	Start2025	PhaseNot applicable	ConditionsDementia and Alzheimer's	Participants70	Lead sponsorOther	StatusRecruiting	Library tests named Trail Making TestSecondary13 weeks Verbal LearningSecondary13 weeks Verbal FluencySecondary13 weeks Digit Span TestSecondary13 weeks Short Story RecallSecondary13 weeks Complex Figure Copy and RecallSecondary13 weeks
NCT07064382	Start2025	PhaseNot applicable	ConditionsDementia and Alzheimer's, Sleep and sleep disorders	Participants60	Lead sponsorOther	StatusNot yet recruiting	Library tests named Digit Span TestPrimary3 years Mental RotationPrimary3 years Route Directions Task and Which-Way-Back GamePrimary3 years

Questions, answered from the data

How many dementia and Alzheimer's trials use the Digit Span Test?

Which tests do dementia and Alzheimer's trials use with the Digit Span Test?

The Trail Making Test (104 studies), Verbal Learning (79 studies) and Verbal Fluency (76 studies).

How many participants do phase 2 dementia and Alzheimer's trials that use the Digit Span Test enroll?

Half of the phase 2 studies that name it enroll 57 participants or fewer, and the middle half enroll 33 to 172. 22 of them give a size.

When do dementia and Alzheimer's trials measure the Digit Span Test?

Half of the primary outcomes that name the Digit Span Test are measured within 6 months of the start, and the middle half from 9 weeks to 2 years. 55 primary outcomes give a duration.

How many completed dementia and Alzheimer's trials that use the Digit Span Test have reported results?

How the studies are counted

Run the Digit Span Test in your trial

Choose tests with a record in registered trials, and run them in a browser at every site, on the same version each visit.

Start free

Digit Span Test in dementia and Alzheimer's trials: 181 registered studies

Tests named in the same studies

Studies by start year

Phases and study sizes

By phase

Participants per study

When dementia and Alzheimer's trials measure it

Latest time point of each outcome

Status, results, interventions and countries

Status

What they test

Where their sites are

Reported results

The 181 studies

Library tests named most

Largest condition groups

Phases

Participants

The studies, newest registration first

Questions, answered from the data

How many dementia and Alzheimer's trials use the Digit Span Test?

Which tests do dementia and Alzheimer's trials use with the Digit Span Test?

How many participants do phase 2 dementia and Alzheimer's trials that use the Digit Span Test enroll?

When do dementia and Alzheimer's trials measure the Digit Span Test?

How many completed dementia and Alzheimer's trials that use the Digit Span Test have reported results?

More on the Digit Span Test and dementia and Alzheimer's disease

The Digit Span Test in other conditions

Other tests in dementia and Alzheimer's trials

How the studies are counted

Run the Digit Span Test in your trial

Digit Span Test in dementia and Alzheimer's trials: 181 registered studies

Tests named in the same studies

Studies by start year

Phases and study sizes

By phase

Participants per study

When dementia and Alzheimer's trials measure it

Latest time point of each outcome

Status, results, interventions and countries

Status

What they test

Where their sites are

Reported results

The 181 studies

Library tests named most

Largest condition groups

Phases

Participants

The studies, newest registration first

Questions, answered from the data

How many dementia and Alzheimer's trials use the Digit Span Test?

Which tests do dementia and Alzheimer's trials use with the Digit Span Test?

How many participants do phase 2 dementia and Alzheimer's trials that use the Digit Span Test enroll?

When do dementia and Alzheimer's trials measure the Digit Span Test?

How many completed dementia and Alzheimer's trials that use the Digit Span Test have reported results?

More on the Digit Span Test and dementia and Alzheimer's disease

The Digit Span Test in other conditions

Other tests in dementia and Alzheimer's trials

How the studies are counted

Run the Digit Span Test in your trial