Pergamon Soc. Sci. Med. Vol. 44, No. 8, pp. 1161-1168, 1997 ~) 1997 ElsevierScience Ltd PII: S0277-9536(96)00262-6 All rights reserved. Printed in Great Britain 0277-9536/97 $17.00 + 0.00 SOCIO-ECONOMIC DIFFERENCES IN GENERAL PRACTITIONER AND OUTPATIENT SPECIALIST CARE IN THE NETHERLANDS: A MATTER OF HEALTH INSURANCE? INGE M.B. BONGERS,-' JOOST B.W. VAN DER MEER,'* JOHANNES VAN DEN BOS' and JOHAN P. MACKENBACH' 'Department of Public Health, Erasmus University Rotterdam, P.O. Box 1738, 3000 DR, Rotterdam, The Netherlands and qVO, Erasmus University Rotterdam, P.O Box 1738, 3000 DR, Rotterdam, The Netherlands A~traet--Equal treatment for equal needs, irrespective of socio-economic position, is a major issue in many countries. Although in the Netherlands differences in utilization of health care between popu- lation groups are less pronounced than in most other countries, some differences by socio-economic position do exist. Controlling for health status, individuals with a high socio-economic status have a higher probability of outpatient contacts with a specialist, but a lower probability of general prac- titioner contacts, compared with those with a low socioeconomic status. In this cross-sectional study, we studied whether socioeconomic differences in GP and outpatient specialist care utilization that exist after health status is taken into account could be explained by different aspects of health insur- ance. The study population, in which people with asthma and chronic obstructive pulmonary disease (COPD), diabetes mellitus, severe back complaints, and heart diseases are overrepresented, consists of 2867 respondents. Multivariate analyses show that the socio-economic differences in outpatient special- ist contacts cannot be explained by differences in health insurance, whereas differences in general prac- titioner contacts can partially be explained by the fact that individuals with higher socio-economic status more often have a private (instead of public) insurance. This is not owing to differences in deduc- tible or insurance coverage between public and private insurance, but is more likely to be caused by differences in regulatory aspects between these two insurance schemes (such as the stronger gate-keeper role of the general practitioner in the public insurance scheme). © 1997 Elsevier Science Ltd Key words~:lelivery of health care, health services, health insurance, social class INTRODUCTION Equal health care treatment for equal health needs, irrespective of factors such as socio-economic pos- ition, is a major issue in many countries (Anonymous, 1994). In the context of health care reform, there is an important issue of which el- ements in the health system are responsible for differential utilization and whether policy measures can affect these differences, if it is felt necessary to change the situation. A recent international comparison of health care systems has shown that in the Dutch system differ- ences in delivery of health care between population groups are less pronounced than in most other countries (van Doorslaer et al., 1993). Still, there are notable differences in health care utilization by socio-economic status in the Netherlands. A study of the Netherlands Central Bureau for Statistics (CBS) shows that after control for health status, people in high socio-economic groups have a higher probability of outpatient specialist contacts, phy- *Author for correspondence. siotherapist contacts, hospital admissions, and non- prescription drugs use (Central Bureau of Statistics, 1991). People in low socio-economic groups, on the contrary, have a higher probability of general-prac- titioner contacts and prescription drug consump- tion. In our study population, similar differences were found (Table l) (van der Meer et aL, 1996). The Dutch health care system is characterized by a combination of two types of health insurance: public and private, which differ with respect to financial and regulatory aspects. The public insur- ance offers a fixed insurance package which is com- pulsory for wage-earners and social security recipients with an annual income under Dfl 58,000 (=approximately $36,000). The public insurance covers about 60% of the Dutch population, the remaining 40% of the population having private insurance. The percentage uninsured is extremely small in the Netherlands (Anonymous, 1992). Most services are free of charge for the publicly insured. In contrast to the publicly insured, the privately insured have the option of accepting a deductible in return for premium reductions, and opting out for part of their health care. A deductible is a set 1161