Executive Function
Block Copy Test
Also called: Kohs-style block task, visuospatial construction task, two-color cube pattern task
Measure visuospatial construction: participants copy red and white patterns by turning blocks, four and then nine, against a time limit.
6-12 minUntimed
Free to start: 10 free participants per account, then $0.99 per participant for academic research, or any yearly plan. Preview any test free after you sign up.
- Papers, 2021 to 2025
- 140
- Evidence grade
- C
- Registered clinical studies
- 33
What it measures
A measure of visuospatial construction after the classic block design paradigm. Participants copy red and white patterns by turning blocks, first with four blocks and then with nine, within a time limit for each pattern. The patterns have no lines between their blocks. The main score is the number of patterns copied, with the time each took.
Constructs
- Visuospatial construction
- Breaking a pattern into parts
- Visual organization
Research uses
- Visuospatial research
- Aging and dementia research
- Within-study group comparison
How the paradigm works
The block copy test measures visuospatial construction: seeing how a pattern is made of parts and building it from blocks. Each screen shows a red and white pattern beside a board of empty places, 2 by 2 and then 3 by 3. Each tap or click on a place turns its block to the next face: all white, all red, then red on one half cut by a diagonal, in four turns. The pattern is drawn without lines between its blocks, so participants have to see where each block's edges would be. A pattern is copied when every block matches it, and the next pattern starts at once.
More about the paradigm
The test has 2 practice patterns and 11 test patterns, five with four blocks and then six with nine, in one fixed order of rising difficulty: more half-red faces, and edges that run across several blocks. Each pattern has a time limit of 60 seconds with four blocks and 120 seconds with nine (standard), or twice that as a setting, and the test stops after three patterns in a row are not copied. The patterns, the faces and the name are our own, after the block design paradigm of Kohs (1920).
The main score is the number of patterns copied. The median time to copy at each size, the share of blocks right when each pattern ended, the turns beyond the fewest that copy each pattern, and the time to the first turn are also reported. Scores support research and do not diagnose.
Scores
- Patterns Copiedcount
- Test patterns whose blocks all matched before the time limit.
- Higher is better
- Patterns Copied, Four Blockscount
- Patterns with four blocks copied in time.
- Higher is better
- Patterns Copied, Nine Blockscount
- Patterns with nine blocks copied in time.
- Higher is better
- Median Four-Block Timems
- Median time to copy a four-block pattern, over the patterns copied.
- Lower is faster
- Median Nine-Block Timems
- Median time to copy a nine-block pattern, over the patterns copied.
- Lower is faster
- Blocks Right%
- Share of blocks matching the pattern when each pattern ended, over the patterns shown.
- Higher is better; credit for patterns nearly copied
- Extra Turnscount
- Turns beyond the fewest that copy each pattern from an empty board, summed over the patterns copied.
- Lower means fewer trial-and-error turns
- Median Time to First Turnms
- Median time from the pattern's onset to the first turn.
- Informational; time spent studying the pattern before acting
- Patterns Not Copiedcount
- Patterns shown that were not copied before the time limit.
- Lower is better
- Patterns With No Turncount
- Patterns in which no block was turned.
- Any is flagged; more than max(3, 25%) is invalid
- Stopped by the Stop Ruleflag
- 1 when the test stopped after three patterns in a row were not copied.
- Informational
- Planned Patternstrials
- Test patterns the session planned to show.
- Informational
- Patterns Showntrials
- Test patterns in the scored run.
- Fewer than planned without the stop rule is flagged for review
Use and evidence
140 papers from 2021 to 2025 name this task in their title or abstract, down 1% compared with 2016 to 2020. That ranks it 159 of 395 test families in our census. See the counts for every test.
Show the numbers
| Year | Papers |
|---|---|
| 2025 | 45 |
| 2024 | 24 |
| 2023 | 26 |
| 2022 | 25 |
| 2021 | 20 |
| 2020 | 37 |
| 2019 | 29 |
| 2018 | 19 |
| 2017 | 25 |
| 2016 | 31 |
| 2015 | 21 |
| 2014 | 31 |
| 2013 | 29 |
| 2012 | 19 |
| 2011 | 20 |
| 2010 | 26 |
| 2009 | 19 |
| 2008 | 22 |
| 2007 | 15 |
| 2006 | 20 |
| 2005 | 14 |
| 2004 | 12 |
| 2003 | 10 |
| 2002 | 9 |
| 2001 | 15 |
| 2000 | 17 |
Use grade C
100 to 299 papers from 2021 to 2025.
Evidence grade C
At least 2 test-retest papers, 30 reliability or validity papers or 3 registered clinical studies.
- Papers on test-retest reliability
- 7
- Papers on reliability or validity
- 113
- Registered clinical studies using it as an outcome
- 33
Note on the counts: phrase includes the commercial subtest.
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 0.14.0, counted 31 October 2026 from OpenAlex and ClinicalTrials.gov.
Task design
The trial sequence as the test runs in ConductCognition.
- Blocks
- Each block's upper face is all white, all red, or red on one half cut by a diagonal. A tap or click turns a block to its next face: all white, all red, then the red half in each corner in turn. An empty place gets an all-white block first.
- Patterns
- 2 practice patterns, then 11 test patterns: 5 with four blocks and 6 with nine, in one fixed order of rising difficulty. Each pattern is drawn in a frame with no lines between its blocks.
- Copied
- A pattern is copied when every block matches it. The board shows Copied for 800 ms, and the next pattern starts.
- Time limits
- 60 seconds with four blocks and 120 seconds with nine (standard), or 120 and 240 seconds as a setting. Each practice pattern allows 120 seconds.
- Stop rule
- The test stops after 3 patterns in a row are not copied.
- Scores
- Patterns copied first, then the median time to copy at each size, the share of blocks right when each pattern ended, turns beyond the fewest needed, and the time to the first turn.
- Screen
- Blocks are buttons sized from the screen, 44 to 96 px wide. The pattern and the board sit side by side on a computer and stack on a phone.
The patterns, the faces and the name are our own. In the classic task people arrange real cubes; here each block is turned in place on the screen, so scores are not comparable with published block design norms.
Quality checks
Each session is marked valid, needs review or invalid, with the reason, before you see its scores.
Scored rows: block_copy_test from the scored run. A pattern copied by random turns is not a simple fraction, so accuracy is not judged against chance. A pattern with no turn before its time limit is a missed response: more than max(3, 25%) invalidate, any is flagged. A run short of its planned patterns that did not end by the stop rule (3 patterns in a row not copied) is flagged for review.
Why these rules
There is no correct option to compare with chance, so accuracy is not judged against chance. A pattern not copied in time already scores as not copied, so a hard pattern is a low score, not missing data; turning no block at all is not an attempt and signals non-engagement.
Running this test
Settings you can change
| Setting | Standard | Allowed |
|---|---|---|
| Time limits | Standard (60 and 120 seconds) | Standard (60 and 120 seconds), Longer (120 and 240 seconds) |
Yearly plans can change settings within these limits. Free and pay-as-you-go studies use the standard settings.
Need a setting this test does not have?
Devices and languages
- Untimed test: runs on desktops, laptops, tablets and phones. 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.
Cite and describe
Participants completed the Block Copy Test in a web browser (ConductCognition task version 1.0.0, scoring version 1.0.0; Kohs, 1920), with the standard settings (time limits: Standard (60 and 120 seconds)). The main score was patterns copied (test patterns whose blocks all matched before the time limit).
ConductCognition versions: task version 1.0.0, scoring version 1.0.0. Every export records the versions each session used, for a methods section.
- Kohs, S. C. (1920). The block-design tests. Journal of Experimental Psychology, 3(5), 357-376. https://doi.org/10.1037/h0074466
- Shah, A., & Frith, U. (1993). Why do autistic individuals show superior performance on the block design task? Journal of Child Psychology and Psychiatry, 34(8), 1351-1364. https://doi.org/10.1111/j.1469-7610.1993.tb02095.xPatterns drawn without lines between their blocks, which makes them harder to copy.
Source papers
- Kohs SC (1920). The block-design tests. Journal of Experimental Psychology, 3(5):357-376.Paradigm source, Not applicable
Questions
How long does the Block Copy Test take?
About 6 to 12 minutes, as listed in the test library.
What device does a participant need?
Untimed test: runs on desktops, laptops, tablets and phones. The browser must be Chrome, Edge, Firefox or Safari.
What scores does it produce?
Patterns Copied, Patterns Copied, Four Blocks, Patterns Copied, Nine Blocks, Median Four-Block Time, Median Nine-Block Time, Blocks Right, Extra Turns, Median Time to First Turn, Patterns Not Copied, Patterns With No Turn, Stopped by the Stop Rule, Planned Patterns and Patterns Shown. Each session is also marked valid, needs review or invalid, with the reason.
How widely is the Block Copy Test used in research?
140 papers from 2021 to 2025 name it in their title or abstract, down 1% compared with 2016 to 2020. That ranks it 159 of 395 test families in the ConductCognition test census (use grade C). Source: ConductCognition test census 0.14.0, counted 31 October 2026 from OpenAlex and ClinicalTrials.gov.
How much reliability evidence does the Block Copy Test have?
In the published research, 7 papers report its test-retest reliability and 33 registered clinical studies use it as an outcome (evidence grade C in the ConductCognition test census).
Which settings can a researcher change?
Time limits (Standard (60 and 120 seconds), Longer (120 and 240 seconds)). Settings can be changed on yearly plans; free and pay-as-you-go studies use the standard settings.
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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