Executive Function
Trail Making Test B
Measure set shifting and cognitive flexibility with a browser-native Trail Making Test Part B.
3-5 minTimed: desktop or laptop with a mouse or trackpad
Free to start: 10 free participants per account, then $0.99 per participant for academic research, or any yearly plan. Try it here first, with no account.
- Papers, 2021 to 2025
- 3,944
- Evidence grade
- A
- Registered clinical studies
- 2,293
What it measures
Measures executive function and cognitive flexibility by asking participants to alternate between numbers and letters (1-A-2-B-3-C...).
Constructs
- Set shifting
- Cognitive flexibility
- Divided attention
- Executive function
- Sequencing ability
Research uses
- Frontal lobe dysfunction detection
- Dementia differential diagnosis
- ADHD executive function assessment
- Traumatic brain injury severity
- Neuropsychological battery standard
How the paradigm works
Trail Making Test Part B measures executive function and cognitive flexibility. Participants must connect circles by alternating between numbers and letters in ascending order (1-A-2-B-3-C-...8-H), requiring constant switching between two cognitive sets. The 16 circles are randomly positioned on a canvas.
More about the paradigm
The critical cognitive demand is set-shifting: participants must maintain two parallel sequences (numeric and alphabetic), track their current position in each, and switch between them on every step. This engages the dorsolateral prefrontal cortex and is one of the most widely used clinical measures of executive function.
The TMT B-A difference (Part B time minus Part A time) is a commonly used derived measure that isolates the executive function component by subtracting out the motor speed contribution measured by Part A. This difference score is particularly sensitive to frontal lobe pathology.
Scores
- Completion Timems
- Total time from first click to connecting the final circle. Primary measure of executive-mediated processing speed.
- Lower is better
- Completion Time (sec)seconds
- Same as completion time, converted to seconds.
- Lower is better
- Errorscount
- Incorrect clicks (wrong circle). In TMT-B, errors often reflect sequencing or set-switching failures.
- Lower is better
- Total Circlescount
- Number of circles in the trail (16 for TMT-B: 8 numbers + 8 letters).
- Informational
Use and evidence
3,944 papers from 2021 to 2025 name this task in their title or abstract, up 22% compared with 2016 to 2020. That ranks it 5 of 582 test families in our census. The counts cover every version of the task, so the Trail Making Test A page shows the same figures. See the counts for every test.
Show the numbers
| Year | Papers |
|---|---|
| 2025 | 944 |
| 2024 | 803 |
| 2023 | 841 |
| 2022 | 648 |
| 2021 | 708 |
| 2020 | 720 |
| 2019 | 667 |
| 2018 | 646 |
| 2017 | 627 |
| 2016 | 576 |
| 2015 | 595 |
| 2014 | 496 |
| 2013 | 449 |
| 2012 | 421 |
| 2011 | 389 |
| 2010 | 330 |
| 2009 | 273 |
| 2008 | 274 |
| 2007 | 199 |
| 2006 | 208 |
| 2005 | 138 |
| 2004 | 98 |
| 2003 | 102 |
| 2002 | 90 |
| 2001 | 85 |
| 2000 | 92 |
Use grade A
1,000 or more papers from 2021 to 2025.
Evidence grade A
At least 25 papers report its test-retest reliability and at least 25 registered clinical studies use it as an outcome.
- Papers on test-retest reliability
- 161
- Papers on reliability or validity
- 1,323
- Registered clinical studies using it as an outcome
- 2,293
Measured on ConductCognition
Pooled across the studies that feed our platform norms, by device group. A figure needs 50 or more people.
No pooled figure yet.
How the grades work
Use: A is 1,000 or more papers from 2021 to 2025, B 300 to 999, C 100 to 299, D 30 to 99 and E fewer than 30. Evidence: A means at least 25 papers report its test-retest reliability and at least 25 registered clinical studies use it as an outcome; B, at least 8 test-retest papers, and either 5 registered clinical studies or 150 reliability or validity papers; C, at least 2 test-retest papers, 30 reliability or validity papers or 3 registered clinical studies; D, little published measurement evidence found. The counts measure use. They include every paper that names the task in its title or abstract. Grades describe the published research on this task, not ConductCognition's version of it.
Source: ConductCognition test census 0.39.0, counted 31 October 2026 from OpenAlex and ClinicalTrials.gov.
Quality checks
Each session is marked valid, needs review or invalid, with the reason, before you see its scores.
Scored row: trailmaking_test. A completion time has no chance level. A trail not finished within 5 minutes is flagged. On a screen shorter than 800 px the percentile is withheld, because the 700 px test area, its instruction line and the progress bar need about 790 px.
Why these rules
There is no correct option to compare with chance, so accuracy is not judged against chance. An unfinished trail is the clinical discontinue result at 300 s, so it is flagged, not invalid. Completion time includes mouse travel; if part of the trail is below the screen edge the participant must scroll during the timed test, which adds time that is not processing speed.
Running this test
Settings you can change
This test runs with fixed settings.
Need a different version of this test?
Devices and languages
- Timed test: participants need a desktop or laptop with a mouse or trackpad. Participant devices
- Languages: English, Spanish, French, German, Italian, Portuguese (Brazil), Chinese (Simplified) and Japanese.
- Available on: Every plan, including the free plan.
- Recruiting online? See the setup guides for Prolific, Sona Systems, CloudResearch Connect and Qualtrics.
Included in these batteries
Each battery runs this test with others in a fixed order, with standard settings.
- Executive Control Battery4 tests, 18 minutes per participant
- Language-Minimized Screening Battery8 tests, 30 minutes per participant
- Older Adult Executive Speed Battery4 tests, 20 minutes per participant
Cite and describe
Participants completed the Trail Making Test B in a web browser (ConductCognition task version 1.0.0, scoring version 1.0.0; Reitan, 1958). The main score was completion time (total time from first click to connecting the final circle).
Paradigm source: Reitan (1958).
ConductCognition versions: task version 1.0.0, scoring version 1.0.0. Every export records the versions each session used, for a methods section.
Source papers
- Tombaugh TN (2004). Trail Making Test A and B: Normative data stratified by age and education. Archives of Clinical Neuropsychology, 19(2):203-214.Paradigm source
Questions
How long does the Trail Making Test B take?
About 3 to 5 minutes, as listed in the test library.
What device does a participant need?
Timed test: participants need a desktop or laptop with a mouse or trackpad. The browser must be Chrome, Edge, Firefox or Safari.
What scores does it produce?
Completion Time, Completion Time (sec), Errors and Total Circles. Each session is also marked valid, needs review or invalid, with the reason.
How widely is the Trail Making Test B used in research?
3,944 papers from 2021 to 2025 name it in their title or abstract, up 22% compared with 2016 to 2020. That ranks it 5 of 582 test families in the ConductCognition test census (use grade A). Source: ConductCognition test census 0.39.0, counted 31 October 2026 from OpenAlex and ClinicalTrials.gov.
How much reliability evidence does the Trail Making Test B have?
In the published research, 161 papers report its test-retest reliability and 2,293 registered clinical studies use it as an outcome (evidence grade A in the ConductCognition test census).
Which languages can participants use?
Participants can take this test in English, Spanish, French, German, Italian, Portuguese (Brazil), Chinese (Simplified) and Japanese. English is on every plan, and the other languages come with yearly plans. Have a native speaker read the machine-translated text before launch.
Is this a clinical test?
No. ConductCognition is for research use only. It runs, scores and exports the test; clinical interpretation is outside the platform.
Every test: the full test list.
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