Equity and medical practice variation: relationships between standardised discharge ratios in total and for selected conditions in English districts

Abstract

Study objective: The aim was to investigate relationships for residents of English district health authorities between rates of discharges from acute hospitals for all conditions and variations in discharge rates for eight common conditions (five surgical, three medical).

Design: Hospital Inpatient Enquiry data on discharges for 1984 were analysed. Standardised discharge ratios (ratios of actual to expected numbers of discharges x 100) were derived for selected conditions and all conditions; and correlation coefficients for these statistics were calculated. Districts were grouped into quintiles according to the value of the standardised discharge ratio, and systematic variation within each quintile was calculated for the selected conditions.

Setting: The study involved all 192 English district health authorities, but 57 were excluded because the proportion of unspecified diagnoses exceeded 5%.

Patients: The analyses were based on 336,799 cases from 135 districts.

Measurements and main results: Discharge ratios for the medical conditions and one surgical condition were significantly correlated with the levels of total discharge rates (p less than 0.01). The medical conditions showed greater systematic variation in discharge ratios than the surgical conditions. There was no consistent pattern in the values of systematic variation for the selected conditions across the different levels of discharge ratios for all conditions.

Conclusions: It is argued that the changes in the NHS introduced in April 1991 are intended to introduce greater equity in the standardised discharge ratios and increase the total numbers of discharges. The results of this analysis suggest that, even if these objectives were achieved, they may not result in increased levels of elective care, nor result in greater equity in terms of rates of discharge for individual conditions.