Document 6b660vEdEL9q6mE2OeX635aJR

RECEIVED KAA o 5 SB* DOW CHEMICAL U.S.A. 1803 Building 14 February 1984 MIDLAND MICHIGAN 486*0 TO: T. R. Torkelson FROM; W. Sobel cc: Dr. Otto Wong, EHA, Berkeley, CA RECEIVED FEB 2 3 1984 ENV HEALTH ASSOC. This note will serve to reiterate the points discussed in our con ference call with Dr. Wong and the CMA Conmittee on February 3, 1984 with regard to the vinyl chloride proposal. 1. The objectives of the study need to be stated. Will the study be hypothesis generating or hypothesis testing? Which specific hypotheses will be tested in the study? 2. In the discussion of the methods of the study, the issue of potential confounders needs to be addressed. Will there be any control for concomitant chemical exposures? 3. There needs to be a more detailed discussion of the sta tistical methods to be used. What are the assumptions and limitations of these methods? 4. The potential for misclassification should be discussed. The possible effect of the dichotomous classification of individuals into exposed and controls should be ad dressed in the proposal. 5. Dr. Ralph Cook will be sending a sample copy of a section of a Dow protocol to Dr. Wong under separate cover. The vinyl chloride proposal should include a short discussion of how the data will be interpreted. This should include what is known about the effects of exposure and the re sults of previous studies of occupational groups exposed to vinyl chloride. The power of the study should also be addressed in this section. AN OPEWATINQ UNIT OP TM| oow CHEMICAL company m CMA 008288