1. A method for assessing the quality of a randomized control trial;Chalmers;Controlled Clin Trials,1981
2. Fundamentals of Clinical Trials;Friedman,1985
3. Clinial Trials: Design, Conduct, and Analysis;Meinert,1986
4. Clinical Trials: A Practical Approach;Pocock,1983
5. Clinical Trials: Issues and Approaches;Shapiro,1983