Abstract
The reliability and validity of a screening test for a deficit in elementary visuo-spatial perception (EVSP) were evaluated. METHOD : This prospective study collected performance from 210 typically-developing individuals and evaluated the internal consistency of the EVSP screening test. Test-retest reliability was examined on 25 individuals. Validity also involved retrospective clinical data collected from 223 non-typically developing children coming to the hospital for out-patient consultation. Since EVSP matures through childhood, we standardized the EVSP screening test scores by age category and performed Pearson correlations with standardized clinical tests scores. RESULTS : Test-retest reliability (intraclass correlation coefficient =.76) and internal consistency (Cronbach's alpha = .76) were satisfactory. Construct validity included correlation with the subtests of the WISC-IV involving visuo-spatial analysis (Matrix Reasoning and Block Design: p<0.01, Symbol Search and Coding: p<0.05) and was reinforced by the expected non-correlation between the Verbal Comprehension Index and EVSP. EVSP correlated with Manual dexterity of the M-ABC (p<0.05) and the Working Memory Index (p<0.05) of the WISC-IV including the subtest Arithmetic (p<0.01). INTERPRETATION : This screening test is reliable and valid to evaluate EVSP before more complex cognitive or motor assessment.