Reliability:
Mean test-retest reliability across test versions is 0.83 (N=41 with an interval of 10 days plus N= 12 with same day re-testing)
Validity:
Relationship between ‘Implicitly’ and an 84 item self-report questionnaire comprising 28 overtly prejudiced beliefs and behaviours, 28 statements from the modern racism research (where underlying prejudices are expressed in a way that avoids sanction) and 28 distracter items. 8 Factors emerged from the self-report questionnaire data. Factor 1 was ‘Overtly prejudiced beliefs and behaviour’. Multiple regression was used to discover which of a number of algorithms underlying Implicitly scores was most predictive of Factor 1. Bi-variate mean correlation between ‘Implicitly’ raw scores and Factor 1 raw scores was calculated to be .45 across two UK population samples (N=318 and N=747)
Score on ‘Implicitly’ is independent of general speed (across tasks) or error proneness.
Studies have shown no impact of IQ. (Gray et al 2003).
Some age effects evident. Older test-takers (>55) showed more prejudicial attitudes against ethnic groups than younger test-takers (<25)
Small sample of people with dyslexia (N=34) tended to produce lower scores and benefited less from practice.