Does induction time have any bearing on definition of study base?
A study population with either a low or high exposure prevalence usually results in a less efficient study, compared with a study on a population with an intermediate exposure prevalence. We discuss a strategy for improving efficiency when exposure is rare: one can include in the study base, for each individual, only follow-up corresponding to a potential exposure-associated increase in risk. This strategy is achieved by choosing so-called preinclusion and preexclusion periods, which, in turn, follow from relevant induction time assumptions.
Department of Occupational and Environmental Medicine, University of Lund, Sweden.
U
U
Strömberg
D016022:Case-Control Studies; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D004812:Epidemiologic Methods; D005500:Follow-Up Studies; D006801:Humans; D012107:Research Design; D013997:Time Factors