The National Hospital Accreditation Program (NHAP) is aimed to assure health care quality and to determine the eligibility of teaching hospitals. In this paper, using 1991 NHAP results, the appropriateness of the measurement scale and the weight of each item designed in the current accreditation program is investigated. Correlation analysis is first used to detect the relevance of measurement indicators preliminary. Then, factor analysis is applied to final determination of distinguishability. The analysis is proceeded with respect to ten major accreditation categories, and within each category both the pooled data of four-level hospitals and the data of combination of medical centers and regional hospitals and combination of district teaching and district non-teaching hospitals are investigated. Those non-dis-tinguishable items are suggested to be reevaluated based on practical needs.