Changes in Connecticut hospital use rates: have small-area variations been affected?

This paper examines the extent to which changes (prospective payment, alternative delivery systems, etc.) in the hospital environment and the general decline in hospital days affect small-area variations in hospital use rates for 18 selected diagnoses in nine hospital service areas in Connecticut. After adjusting for coding changes between DRGs, we found that variation across the service areas did not, in general, differ for any one of the years 1981-86. In one instance (cardiac catheterization), however, we found that a DRG-specific change in knowledge and technology decreased the extent of small-area variation for that diagnosis.