SMALL-AREA VARIATIONS IN THE RATE OF OPER ATIONS FOR HIP FRACTURE IN THE CANTON OF VAUD

Objectives: Studies of small area variations of health care utilizatio n are more and more frequent. Such variations are often considered to be an indication of variations in the quality of medical care. The var iations in the rate of operations for hip fractures are among the lowe st studied to date, due to the fact that a consensus exists concerning this surgery. Our objective is to examine these variations within the context of relatively small and heterogeneous districts. Method: Base d on anonymous computerized data on public hospital stays, this study describes the variations in population rates (crude and standardized) of operations for hip fracture among the health districts of the Canto n of Vaud for the period from 1986 to 2998. District populations vary from 22,000 to 164,000. Using the extremal quotient (EQ), the importan ce of these variations was determined. Results: The study population c onsists of 2363 cases, of which 78% are women. Mean age is 80.4 for wo men and 70.6 for men. Standardized rates of operation for hip fracture per 100,000 in the Canton Vaud for the years 1986 to 1991 are, respec tively: 56; 67; 86; 91; 89 and 94. The EQ for the years 1986 to 1991 a re respectively: 8.2; 4.0; 3.5; 2.7; 1.9 and 1.9. The high EQ, especia lly for the earlier years, are contrary to the initial premise of abse nce of variation. The progressive implementation in the Canton Vaud of VESKA medical statistics could play a role, as could the small size o f many of the districts, with resultant instability of rates. Conclusi ons: Considering the wide variations shown here for an operation hardl y regarded as subject to variations, it is important to exercise cauti on in interpreting published data of small area variations.