Test-retest reliability and practice effect of the Test of Visual Perceptual Skills-4th Edition for individuals with schizophrenia

Abstract

Abstract Background The Test of Visual Perceptual Skills-4th Edition (TVPS-4) is widely used for repeated measures of visual perception. This study aims to examine the test-retest reliability and practice effect of the TVPS-4 in individuals with schizophrenia receiving care in community psychiatric rehabilitation facilities. Methods A repeated assessment design was employed, involving 80 participants. Test-retest reliability was evaluated using the intraclass correlation coefficient (ICC). Minimal detectable change (MDC) values were calculated at 95%, 90%, and 80% confidence levels. The MDC% was determined based on the MDC with 95% certainty. Cohen's d effect sizes and paired t-tests were utilized to assess the practice effect. Results The ICCs of the overall scale and the seven subscales of the TVPS-4 were 0.93 and 0.59–0.84, respectively. The MDC95 (MDC%), MDC90, and MDC80 ranged from 4.7–16.3 (13.2–34.8%), 3.9–13.6, and 3.1–10.6, respectively. Cohen’s ds were 0.06–0.26 and paired t-test showed significant differences in scores of the overall scale and the four subscales (p < 0.05). Conclusion The TVPS-4 has acceptable test-retest reliability and trivial to small practice effect, and the MDCs at different confidence levels can be used to interpret the score changes at a particular level of certainty for individuals with schizophrenia.