The comparison of health care systems through regional analysis: the case of hospital admissions in Belgium and The Netherlands.

One of the problems in the international comparison of health care systems is the small number of units of analysis. Usually only a small number of systems is compared which makes cross-sectional statistical analysis impossible. The two obvious solutions to this problem--neither of which is generally feasible--are either to enlarge the number of systems being compared or to use time series on a small number of health care systems. Quite another solution is to study regional variations within and between a small number of systems. The number of regions has to be sufficiently large to make statistical analysis possible. This is the solution chosen in this article. The phenomenon which is central to our analysis is the number of hospital admissions per 1000 of the population. To explain variations in the hospital admission rate, it is hypothesized that there are a number of variables that have the same kind of influence on hospital admission rates in all western industrialized countries (such as the supply of hospital beds and the health status of the population). On the other hand there are determinants of regional variation in the number of admissions which either exert an influence dependent on the nature of the system, or are unique to a particular health care system. Concerning the first group of hypotheses (the general model), our analysis based on data for 1974 showed that the only variables to have a clear and equal influence on the regional variation in hospital admission rates in the Netherlands as well as in Belgium are the number of hospital beds per 1000 inhabitants and standardized mortality (an operationalization of the concept of health status). The influence of system-specific variables (the second group of hypotheses) has been analysed, taking the difference between the actual number of admissions and the number of admissions expected on the basis of the number of beds and mortality as the dependent variable. In the Netherlands, none of the variables appears to have a clear influence on the level of this ratio, whereas in Belgium there is a greater number of admissions than expected in regions with a higher birth-rate and a higher number of both general practitioners and specialists in the common disciplines (internal medicine, pediatrics, gynaecology) in relation to the total number of specialists.