1. The Burlington randomized trial of the nurse practitioner;Spitzer;New Engl J Med,1974
2. What is a health care trial?;Spitzer;JAMA,1975
3. Quality-of-care appraisal in primary care: a quantitative method;Sibley;Ann Intern Med,1975
4. The case-control study: the problem and the prospect;Ibrahim;J Chronic Dis,1979
5. Report of the Canadian task force on the periodic health examination;Spitzer;Can Med Assoc J,1979