Planning and Evaluation of Studies on Atherosclerosis in Controlled Clinical Trials

  • Stanley Azen
  • David H. Blankenhorn
  • Sharon Nessim


The Cholesterol Lowering Atherosclerosis Study, Phase I (CLAS-I), is a prospective, controlled, angiographic clinical trial designed to evaluate the effectiveness of aggressive cholesterol lowering therapy for the treatment of atherosclerosis. We report here the methodological aspects in planning and evaluating angiographic clinical trials. Consideration is given to choice of the study population, allocation ratios, design of the experiment, and to the evaluation of measurement error and sample sizes. CLAS-I is used to illustrate the points discussed in this paper.


Carryover Effect Coronary Angiogram Allocation Ratio Arterial Injection Compliance Score 
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Copyright information

© Springer Science+Business Media New York 1984

Authors and Affiliations

  • Stanley Azen
    • 1
  • David H. Blankenhorn
    • 1
  • Sharon Nessim
    • 1
  1. 1.Departments of Preventive Medicine and Medicine, School of MedicineUniversity of Southern CaliforniaLos AngelesUSA

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