The d2‑R (d2 Test of Attention – Revised) is a widely used assessment of selective and sustained attention and concentration. It measures a variety of facets, including: processing speed, accuracy of visual scanning, coordination of speed and accuracy, control of attention, inhibitory control, cognitive flexibility, consistency in work speed and persistence, rule compliance, and motivation for the tasks.

What the d2‑R Measures

The d2R is a time-pressured visual scanning task in which participants must identify specific target characters while ignoring highly similar distractors. Performance is reported across multiple facets of attention, which include:

• Concentration Performance: Reflects the ability to process information quickly while maintaining accurate, focused attention and avoiding errors.
• Processed Targets: Reflects the speed at which an individual scans and processes visual information, independent of accuracy.
• Accuracy: Reflects how accurately an individual responds, with minimal missed targets or incorrect responses.
• Validity Checks: Very high errors or unusual response patterns may suggest random or uncooperative responding and are flagged.

Why Organisations Use the d2‑R

• The tool is valuable in selection contexts where critical safety behaviours are tied to the avoidance of unnecessary attentional errors, such as in transport, pharmaceuticals, aviation, editing, and sport.
• It provides a quick assessment of attention and concentration, making it practical for large‑scale or time‑limited assessments.
• The test is widely used and supported by extensive research, with evidence of high reliability and validity across different age groups.

Key Features

• A brief 10-minute online visual scanning task of 14 timed screens, where individuals identify target symbols among similar distractors, with instant reporting after assessment completion.
• Suitable for ages 18 to 55 years.
• The norms of European-based.
• Language versions include English, German, Czech, Slovak, Finnish, Swedish, and Norwegian.

Report Outputs

A technical report that contains standard and T-scores is provided. Qualitative information, based on scoring bands, is provided to help interpret the scores.

Applications

• Organisations commonly use the d2R as part of the selection process to screen candidates who are likely to make errors in safety-critical roles. Results may be used to rank applicants or, when combined with other assessment methods, to inform an overall evaluation of candidate suitability.
• Used to identify high attention performers.
• Determining suitability for further training in settings where high concentration is required.
• Workforce planning to assess readiness for roles where attentional failing includes risk, including transport roles, warehouse operations, quality control, security, airside/air traffic roles, and technical operators.
• Used as a benchmark predictor when evaluating the incremental validity of other psychometric assessments when predicting future risk and safety-related outcomes.