"We analysed the relative importance of individual versus institutional factors in explaining variations in the utilisation of physician services among the 50+ in ten European countries. The importance of the latter was investigated, distinguishing between organisational (explicit) and cultural (implicit) institutional factors, by analysing the influence of supply side factors, such as physician density and physician reimbursement, and demand side factors, such as co-payment and gate-keeping, while controlling for a number of individual characteristics, using cross-national individual-level data from SHARE. Individual differences in health status accounted for about 50 percent of the between-country variation in physician visits, while the organisational and cultural factors considered each account for about 15 percent of the variation. The organisational variables showed the expected signs, with higher physician density being associated with more visits and higher co-payment, gate-keeping, and salary reimbursement being associated with less visits. When analysing specialist visits separately, however, organisational and cultural factors played a greater role, each accounting for about 30 percent of the between-country variation, whereas individual health differences only accounted for 1 percent of the variation"--National Bureau of Economic Research web site.