Trends in hospital use for mechanical neck and back problems in Ontario and the United States: discretionary care in different health care systems.

OBJECTIVE: To describe and compare trends in hospital admission rates for mechanical neck and back problems between 1982 and 1992 in Ontario and the United States. DESIGN: A descriptive analysis of hospital admissions, with data for Ontario extracted from the Canadian Institute for Health Information database and data for the US extracted from the National Hospital Discharge Survey. SETTING: All acute care hospitals in Ontario and a probability sample of acute care hospitals in the US. PATIENTS: Adults aged 20 years or more who were admitted to an acute care hospital for mechanical neck or back problems in 1982, 1987 or 1992. Mechanical neck and back problems were defined using an algorithm developed by the study team. OUTCOME MEASURE: Hospital admission rate per 100,000 adults. RESULTS: Between 1982 and 1992 the hospital admission rate for medically treated cases decreased by 52% in Ontario and by 75% in the US. Over the same period the admission rate for surgically treated cases increased by 14% and by 35% respectively. By 1992 the admission rate for medically treated cases in the US was 23% higher than that in Ontario, whereas the rate for surgically treated cases was 164% higher. CONCLUSIONS: The hospital-based medical or surgical treatment of mechanical neck and back problems provides an example of discretionary care. The higher admission rates for surgery in the US may reflect a larger supply of surgical specialists and imaging units. Further work is needed to confirm these findings for other types of discretionary care and to compare the appropriateness of care and clinical outcomes for discretionary care in these 2 jurisdictions.