The quality-costs of an analytical process: 1. Development of quality-costs models based on predictive value theory

General considerations are presented for the development of quality-costs models based on predictive value theory [12]. Quality-costs include costs for prevention, appraisal (surveillance), and failure [1]. Failure-costs are due to incorrect analytical runs (medically important analytical errors by the measurement procedure) and incorrect decisions on the status of analytical runs (misclassifications by the control procedure). Failure-costs depend on characteristics of the measurement procedure (f, frequency of medically important analytical errors) and characteristics of the control procedure (ped, probability for error detection; pfr, probability for false rejection). An approach is presented for developing quantitative relationships to predict failure-costs based on these critical process characteristics. Efforts to provide cost effective analytical processes should be aided by models which can relate quality-costs to characteristics of the measurement and control procedures.