Under-ascertainment of IID was substantial (36%) and non-random and had to be corrected. Practice characteristics influencing variation in ascertainment were identified and a multivariate model developed to identify adjustment factors which could be applied to individual practices. Researchers need to be aware of factors which influence ascertainment in acute epidemiological studies based in general practice.

WD is a diverse chronic disease with generally favourable outcomes for patients who respond to initial therapy, which can be managed predominantly in an ambulatory setting.

No abstract