UK Biobank: Protocol for a large-scale prospective epidemiological resource

The inclusion of at least 500,000 individuals is the result of consideration of the number of events required for the reliable quantification of a number of different factors on a range of diseases (see below), as well as practical concerns regarding design and cost. [...] For example, reducing the misclassification rate for the environmental exposure from 20% to 10%, and the proportion of non-diseased subjects incorrectly inferred to be cases from 0.2% to 0.045%, reduces the MDORs (for p<10-4) for the genetic and environmental main effects and for the interaction term from 1.32 to 1.24, 1.66 to 1.33, and 2.35 to 1.81, respectively, in a study with 5,000 cases and 2. [...] These criteria included: the perceived strength of knowledge or hypotheses about exposure-disease relationships; the public health importance of the relevant condition; the likely importance of factors that might act as confounders or sources of bias; the reliability and validity of questionnaire measures; and the availability of alternate sources of information about the factor (including biometr. [...] 1.3.2 Questionnaire structure and administration Due to the large size of the UK Biobank cohort, the approach to data capture aimed to optimise the accuracy and completeness of the data collected, while also maximizing the efficiency of the process. [...] the range of assays that could be made and the physiological coverage of the material), and the feasibility and cost of collecting and processing such samples from the 500,000 participants.