OBJECTIVE: To measure variability in the use of primary care resources and identify factors that explain the differences. DESIGN: An ecological observation study. SETTING: Primary care. PARTICIPANTS: The 1996 index of frequency of attendance was chosen as the indicator of primary care resource use throughout the territory managed by INSALUD. INTERVENTIONS: The analysis was conducted on a provincial basis, using the statistical technique of multiple linear regression. The index of frequency of attendance was chosen as dependent variable; and demographic, social and economic, mortality, organisation, and offer and accessibility indicators were chosen as explanatory or independent variables. MEASUREMENTS AND RESULTS: There was wide variability in frequency of attendance in the areas managed by INSALUD during 1996, with a variation coefficient of 20.5%. The simple linear regression analysis showed that the population's income explained 55% of variability. Income, the number of doctors per 1,000 inhabitants and the percentage of children under 3 explained 70% of the variability of frequency of attendance at primary care. CONCLUSIONS: There are differences between provinces in primary care health resource use. Attendance for primary care consultation in INSALUD is more frequent in provinces with a low social and economic level, more doctors per 1000 inhabitants and more children under 3.
OBJECTIVE: To measure variability in the use of primary care resources and identify factors that explain the differences. DESIGN: An ecological observation study. SETTING: Primary care. PARTICIPANTS: The 1996 index of frequency of attendance was chosen as the indicator of primary care resource use throughout the territory managed by INSALUD. INTERVENTIONS: The analysis was conducted on a provincial basis, using the statistical technique of multiple linear regression. The index of frequency of attendance was chosen as dependent variable; and demographic, social and economic, mortality, organisation, and offer and accessibility indicators were chosen as explanatory or independent variables. MEASUREMENTS AND RESULTS: There was wide variability in frequency of attendance in the areas managed by INSALUD during 1996, with a variation coefficient of 20.5%. The simple linear regression analysis showed that the population's income explained 55% of variability. Income, the number of doctors per 1,000 inhabitants and the percentage of children under 3 explained 70% of the variability of frequency of attendance at primary care. CONCLUSIONS: There are differences between provinces in primary care health resource use. Attendance for primary care consultation in INSALUD is more frequent in provinces with a low social and economic level, more doctors per 1000 inhabitants and more children under 3.