In utero exposures, season of birth and population studies of older adults: Author’s reply

In their commentary “Reconstructing dose,” Catalano, Margerison-Zilko, Saxton, LeWinn, and Anderson (2011) do not invalidate the finding that in utero exposures may be important in later adult health. They bring to attention four major areas of contention: (1) different in utero mechanisms that could explain associations with older adult health; (2) early life mortality rates and proportions in making inferences about season of birth; (3) measurement of older adult health and its determinants using population studies and historical data; and (4) relevance to public health research. There is general agreement between us in regards to the importance of in utero exposures and older adult health and the issues of measurement in population studies of older adults. There is disagreement in the interpretation of my results.