1. The definition of quality and approaches to its assessment;Donabedian,1980
2. The criteria and standards of quality;Donabedian,1982
3. Methods of assessing quality of medical care;Morrell,1970
4. Variations in the use of medical and surgical services by the Medicare population;Chassin;New England Journal of Medicine,1986
5. Small-area variations in the use of common surgical procedures: an international comparison of New England, England and Norway;McPherson;New England Journal of Medicine,1982