Construct validity of the Capacity Profile in adolescents with cerebral palsy.

OBJECTIVE To establish construct validity of the Capacity Profile, a method to comprehensively classify additional care needs in five domains of body functions (physical health, motor, sensory, mental, voice and speech functions), in adolescents with non-progressive, permanent conditions such as cerebral palsy. DESIGN Cross-sectional study. SUBJECTS Ninety-four adolescents with cerebral palsy: 60 boys, 34 girls, median age 14.3, range 12-16 years, unilateral (n = 37), bilateral (n = 57), spastic (n = 76), ataxic (n = 4), dyskinetic (n = 5), mixed (dyskinetic and spastic, n =9), Gross Motor Function Classification System: level I (n = 50), level II (n = 6), level III (n = 10), level IV (n = 8), level V (n = 20). METHODS Associations were calculated between Capacity Profile domains and Vineland Adaptive Behavior Scales (communication, daily activities, social and motor skills) and Gross Motor Function Classification System using Spearman's rho. Furthermore, we explored the independent contribution of the Capacity Profile domains to activities and participation measured with the Vineland Adaptive Behavior Scales. RESULTS All Capacity Profile domains were significantly associated with all domains of the Vineland Adaptive Behavior Scales and the Gross Motor Function Classification System (P<0.05). Multiple regression analysis showed that the Capacity Profile contributed 87% to variance in communication (Capacity Profile-voice 78%, mental 8% and physical 1%), 85% to daily activities (Capacity Profile-mental 75%, motor 8% and voice 2%), 60% to social skills (Capacity Profile-voice 56% and mental 4%), and 91% to motor skills (Capacity Profile-motor 87%, mental 3% and sensory 1%). CONCLUSION These findings support the construct validity of the Capacity Profile in adolescents with cerebral palsy. Construct validity in other medical conditions should be further investigated.