Mechanism of action and impact of a cystitis clinical practice guideline on outcomes and costs of care in an HMO.

BACKGROUND: A study was conducted in 1995 at five primary care clinics of a staff-model health maintenance organization in the Midwest to assess the impact of a cystitis clinical guideline and to help elucidate the guideline implementation process. METHODOLOGY: Two hundred one eligible women with uncomplicated cystitis were treated in a three-month period before the guideline, and 241 similar cases were treated in a three-month period after the guideline. Nursing supervisors and clinic managers at each clinic were interviewed about how the cystitis guideline was implemented at each clinic. RESULTS: Use of a recommended three-day antibiotic treatment increased from 28% to 52% of cases (chi-square = 25.01, p < 0.001). Use of urine cultures decreased from 70% to 37% of cases (chi-square = 48.19, p < 0.001). The proportion of eligible cystitis cases coordinated primarily by the nurse increased from 21% to 78% (chi-square = 142.93, p < 0.001). However, desired changes in use of antibiotics and urine cultures were limited to nurse-coordinated cases. There was no increase in hospital admissions, emergency room visits, repeat office visits (p > 0.05), or repeat antibiotic courses (p > 0.05) after cystitis guideline implementation. Cost of cystitis care delivered after guideline implementation was 35% lower than before guideline implementation. CONCLUSIONS: Use of the guideline was associated with desirable changes in antibiotic use, nurse coordination of care, costs of care, and comparable clinical outcomes. Clinics that used clinical systems and tools to support nurse-coordinated cystitis care had greater guideline adherence than clinics that did not support nurse-coordinated care.