Avoidable hospitalisation rates in Singapore, 1991-1998: assessing trends and inequities of quality in primary care.

STUDY OBJECTIVES To assess avoidable hospitalisation as an indicator of quality of primary care by examining trends and gender and ethnic variations. DESIGN AND SETTING Aggregated nationwide data in Singapore from 1991 to1998 were analysed for hospitalisations for chronic diseases that are avoidable by timely, appropriate, and effective primary care: asthma, congestive heart failure, chronic obstructive pulmonary disease, diabetes mellitus, and hypertension (avoidable hospitalisations). MAIN RESULTS Of a total of 1 479 494 hospitalisations, 6.7% were for ambulatory care sensitive conditions (ACSC). The annual rate of avoidable hospitalisation was 29.4 per 10 000 population. Women had lower rates of avoidable hospitalisations than men (22.4 versus 29.5 per 10 000), as well as for total hospitalisations (496.2 versus 515.5 per 10 000). Adjusted for total hospitalisation, men were 1.3 times more likely than women to be hospitalised for ACSC. With similar adjustments for baseline utilisation, Indian and Malays had 1.7 and 1.8 times higher rates of avoidable hospitalisations than Chinese. Avoidable hospitalisation decline was -9.1% overall; greater in men (-11.8%) than in women (-5.3%); greater for Chinese (-15.8%), than Malays (-1.1%) and Indians (increase of +4.3%). CONCLUSION Gender and ethnic differences and declining trends in avoidable hospitalisation demonstrated in this study suggest that avoidable hospitalisation rates are a sensitive indicator for assessing quality of primary ambulatory care.