MARGINAL REGRESSION FOR REPEATED BINARY DATA WITH OUTCOME SUBJECT TO NON-IGNORABLE NONRESPONSE

Using a model that accounts for non-ignorable non-response, we analyze d data from the Muscatine Risk Factor Study (Woolson and Clarke, 1984, Journal of the Royal Statistical Society, Ser-ies A 147, 87-99) on th e effects of gender and age on obesity in schoolchildren, The methodol ogy is related to that of Diggle and Kenward (1994, Applied Statistics 43, 49-93), except that the repeated data are binary, not continuous, and the non-response occurs in various patterns, not just dropouts. W e found strong evidence that non-response was non-ignorable. In additi on, we found that the proportion of children who were obese differed s ignificantly with gender and increased with age.