Composite Health Plan Quality Scales

This study employs exploratory factor analysis and scale construction methods with commercial Health Plan Employers Data Information Set (HEDIS(®)) process of care and outcome measures from 1999 to uncover evidence for a unidimensional composite health maintenance organization (HMO) quality scale. Summated scales by categories of care are created and are then used in a factor analysis that has a single factor solution. The category of care scales were used to construct a summated composite scale which exhibits strong evidence of internal consistency (alpha= 0.90). External validity of the composite quality scale was checked by regressing the composite scale on Consumer Assessment of Healthcare Providers and Systems (CAHPS(®)) survey results for 1999.