Method notes
Method notes are the published procedures behind Stroop's numbers: what the scoring and timing code does, step by step, and the papers it follows.
Updated . Scoring version 2026.10.0.
If a client's analyst asks how a D-score or a directness figure was worked out, send them here. Every score Stroop stores carries the version of the code that computed it, and a note changes in the same release as the formula it describes.
- How Stroop scores an IATThe improved D algorithm step by step, its six variants, exclusions and the brief IAT's procedure.
- How Stroop times responsesFrames, clocks and the timing grade, how the homepage test differs, and what we haven't measured yet.
- How Stroop scores the SUSBrooke's ten items to a 0 to 100 score, the grade and the percentile, with a worked study.
- Tree test metrics: success, directness and the pietreeThe six outcomes, the intervals, first clicks and what each pietree slice means.
- Card sort analysis: similarity and clusteringFrom participants' groups to the similarity matrix and an average-linkage dendrogram.
The methods themselves, with prices, are on the methods page. Stroop is the all-in-one research and testing platform. Run usability tests, prototypes, surveys, tree tests, diaries and IATs in one study, and get results back transcribed, scored and charted, with every finding linked to the session it came from.