A likelihood based method for analysing overdispersed correlated count data with subject specific covariates

In this talk I will develop a robust likelihood approach for the analysis of correlated count data that takes into account cluster varying covariates. The method will be illustrated through the analysis of data from two studies. In the first study, cross-sectional count data from a randomised controlled trial are analysed to evaluate the efficacy of a communication skills training programme. The second study involves longitudinal count data which represents counts of damaged hand joints in patients with psoriatic arthritis.