[Variable rates of diseases in health survey and family practitioners' registries]

To compare the data from the health survey of the Central Bureau for Statistics (CBS: about episodes of chronic diseases experienced by those questioned) and from general practice registration projects (regarding episodes of care).

Descriptive.

Department of General Practice, Academic Medical Centre, Amsterdam, the Netherlands.

Frequency figures from the CBS health survey regarding chronic diseases for 1992 were compared with data from three large continuous general practice registration projects: the Amsterdam Transition Project, the Nijmegen Continuous Morbidity Registration and the fourth British National Morbidity Study. From the Transition Project not only one-year data were used but also data referring to a four-year period (1989/'93).

Incidence and prevalence figures concerning illness and care were in good agreement regarding cardiovascular diseases, uterine prolapse, diabetes mellitus, thyroid disorders, epilepsy and cancer. The health survey had higher frequencies than the GP registration for respiratory disorders, hypertension (both mostly in the age group 25-44 years) gastrointestinal disorders, articular disorders and migraine. With regard to a number of diseases, the four-year registration was in better agreement with the health survey than the one-year registration (e.g. joint disorders): with other disorders the reverse was true (e.g. stroke).

There were similarities as well as differences between the frequencies from the health survey and the general practice registration projects. Regarding a number of these differences interpretation was possible by using not only one-year data from the GP practice but also data concerning a longer period (4 years) and by comparing the information for different age groups.