Structure of the Minnesota Developmental Programming System Behavioral Scales, Alternate Form C

The Minnesota Developmental Programming System Behavioral Scales, Alternate Form C, designed to assess adaptive behavior of profoundly developmentally disabled individuals, was evaluated using data from 3,487 individuals. Relative difficulty within each of four 20-item subscales (Gross Motor, Eating, Environmental Integration, and Language/Communication) deviated slightly from the original instrument description. Factor analyses with orthogonal rotation revealed six factors with high loadings on, respectively: (a) difficult items from all subscales, (b) items from both Gross Motor and Eating subscales, (c) items from both Environmental Integration and Language/Communication subscales, and (d) items within each individual subscale except Language/Communication. Oblique rotation suggested two factors for each subscale, one loading on easier items and one loading on more difficult items. Factor patterns after oblique rotation were similar for four age groups ranging from young children (less than 5 years) to adults (over 30 years). Factor analyses of items within each subscale showed predominance of a single factor and no strong evidence of subscale multidimensionality. These results, in large part, confirmed the original Form C description.