Reliability, criterion-related validity and qualitative comments of the Fourth Edition of the Stanford-Binet Intelligence Scale with a young adult population with intellectual disability

The test-retest reliability and concurrent, criterion-related validity of the Fourth Edition of the Stanford-Binet Intelligence Scale (SB-IV) were examined in a young adult population with intellectual disability. Forty adults with mild to moderate intellectual disability (mean age = 20.8 years; SD = 1.8 years) were administered the SE-IV and retested approximately 5 weeks later (mean = 33.4 days, SD = 1.2). The Vineland Adaptive Behavior Scale: Interview Edition (VABS) was completed by a reliable informant within one week of the SB-IV testing. The test-retest reliability coefficients for the four SB-IV area and composite scores were all significant (P < 0.001). Individual subtest correlations tended to be lower but consistent across the two administrations. Moderate correlations were observed between the VABS composite and SB-IV composite scores. The present results provide support for the temporal reliability of the SB-IV and its concurrent, criterion-related validity in an exceptional sample.