An empirical assessment of the validity of explicit and implicit process-of-care criteria for quality assessment

OBJECTIVE. TO evaluate the validity of three criteria-based methods of qual ity assessment: unit weighted explicit process-of-tare criteria; differenti ally weighted explicit process-of-care criteria; and structured implicit pr ocess-of-care criteria. METHODS. The three methods were applied to records of index hospitalization s in a study of unplanned readmission involving roughly 2,500 patients with one of three diagnoses treated at 12 Veterans Affairs hospitals. Convergen t validity among the three methods was estimated using Spearman rank correl ation. Predictive validity was evaluated by comparing process-of-care score s between patients who were or were not subsequently readmitted within 14 d ays. RESULTS. The three methods displayed high convergent validity and substanti al predictive validity. Index-stay mean scores, using explicit criteria, we re generally lower in patients subsequently readmitted, and differences bet ween readmitted and nonreadmitted patients achieved statistical significanc e as follows: mean readiness-for-discharge scores were significantly lower in patients with heart failure or with diabetes who were readmitted; and me an admission work-up scores were significantly lower in patients with lung disease who were readmitted. Scores derived from the structured implicit re view were lower in patients eventually readmitted but significantly so only in diabetics. CONCLUSIONS. These three criteria-based methods of assessing process of far e appear to be measuring the same construct, presumably "quality of care." Both the explicit and implicit methods had substantial validity, but the ex plicit method is preferable. In this study, as in others, it had greater in ter-rater reliability.