Community income and surgical rates in the Netherlands.
BACKGROUND
The study describes variations in use of surgical procedures by community income in the Netherlands. From the literature it is known that surgical rates have a socioeconomic gradient. Both positive and negative associations of socioeconomic factors of patients (for example, income, education) with surgical rates have been reported. The question raised here is: how do (possible) socioeconomic variations in surgery in the Netherlands compare with variations observed elsewhere?


METHODS
The data comprised Dutch hospital discharges and population estimates for 1999. Socioeconomic status was indicated by a patient's income and based on the average family income of the postcode area of residence. Poisson regression was used to compute relative incidence (odds ratios) for 10 common surgical procedures. The model included age, gender, degree of urbanisation, and province of residence.


RESULTS
The association between surgical rates and community level income is rather weak. For half of the surgical rates the authors observed higher utilisation rates in communities with low income levels, but the differences are small. The range of odds ratios in the lowest income quintile group (compared with the group with the highest income) observed is: 0.87 to 1.18. Men from a low income community received more appendicectomies (1.18), cholecystectomies (1.12), knee replacements (1.06), and prostatectomies (1.14) and less tonsillectomies (0.90). Women from a low income community received more appendicectomies (1.12), caesarean sections (1.18), hip and knee replacements (1.05,1.17), and hysterectomies (1.14). Whereas they received less coronary artery bypass grafts (0.92), cholecystectomies (0.87), and tonsillectomies (0.92).


CONCLUSIONS
Compared with findings reported in the international literature, this study indicates that variations in use of surgical procedures by community income in the Netherlands are comparatively small. Because of lack of data the authors could not study the influence of variations in need for surgical care by community income, but as the incidence of conditions requiring surgical interventions generally is higher in lower income groups, it is suspected some degree of underutilisation exists in these groups.
Westert
G P
GP
Centre for Prevention and Health Services Research and Public Health Forecasting, National Institute for Public Health and the Environment, Bilthoven, Netherlands. gert.westert@rivm.nl
Smits
J P J M
JP
Polder
J J
JJ
Mackenbach
J P
JP
D005260:Female; D006801:Humans; D007182:Income; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D016017:Odds Ratio; D012923:Social Class; D013514:Surgical Procedures, Operative / Q000191:economics / Q000706:statistics & numerical data*