Comparison of short and long versions of the Prudhoe Cognitive Function Test and the K-BIT in participants with intellectual impairment.

The Prudhoe Cognitive Function Test (PCFT) directly measures the cognitive abilities of people with intellectual impairment. This study examined the relationship between this instrument and the Kaufman Brief Intelligence Test (K-BIT) and two shorter versions of the same scale. High correlations between the verbal and performance sections of the K-BIT and the Long PCFT were found with correlation coefficients of 0.85 and 0.78, respectively. Extremely high correlations between the Short versions of the PCFT and the Long version were obtained at 0.97 for Form A and 0.98 for Form B, illustrating that both Short forms and the Long form are essentially interchangeable. The PCFT is a reliable and robust schedule in the assessment of cognitive function in this population.