Document jBzGaEqzyNKnZo9nB7ZMNypxk

AIA-103 THE UNIVERSITY OF MICHIGAN School of Public Health DEPARTMENT OF EPIDEMIOLOGY 109 Observatory Street Ann Arbor, M/ch/gan 4s tog August 24, 1977 Professor Philip E. Enterline Department of Biostatistics Graduate School of Public Health University of Pittsburgh Pittsburgh, PA 15261 Dear Phi 1: I am sorry to have been so slow in sending you my thoughts and conclusions from my review of the asbestos literature. I have, however, put in a good many hours on this - many of them in spells on vacation out at the lake! . I started before you sent me the results of your review but did not quite finish the 1963 to 1965 papers. More recently, I have been going through all the papers again. I have checked my agreement with your assessments. On the whole we agree very well. I wonder most about assess ments of risk of cancer in the absence of asbestosis. But, I believe this is still a question which is open to some doubt. One weakness of the enterprise seems to me to be that what an investi1 gator concluded was often more a reflection of his credulity than a true | reflection of the evidence. Nordman was a man of strong views - a believer j if you like - Gloyne on the other hand was much more cautious. i I There seem to be real international differences. These should be con i sidered in your review. Some of the explanations are: Duration of use (Finland, Italy). Type of asbestos; length of fiber, associated exposures, conditions of exposure, impurities in the dust and of course the quite re markable ignoring of cigarette smoking even until quite recently. I wonder if your review should stop in 1965? I agree that by then it j has become virtually impossible not to believe that exposure to asbestos caused lung cancer and meso theliomas. But should any later nails be added to the coffin? Do you want to say anything about the "other cancers" question? This is still debatable of course; but it is certainly of great interest. I think it is important to emphasize the non-statistical biological reasons for concluding that asbestos caused lung cancer. I refer particu larly to the high proportion of females, lower lobes, multicentric origin, earlier age of onset than ordinary lung cancer etc. My reading of the literature is that these things determined many peoples conclusions far ! more than the statistical evidence. AIA-103 Professor Philip E. Enterline August 24, 1977 Page two I have made additional notes on your forms and on sheets of paper. I am sending you xerox copies. I hope they will be useful and at least, stimulating. This is the sort of enterprise one never finishes. I could certainly continue to review papers for quite a time. I feel, however, I must get something off to you now. Let me know if I can be of further help, in particular over any debatable points. Best wishes. Sincerely yours. ITTH/jlf end osure Ian T. T. Higgins, M.D. Professor of Epidemiology