The role of patients and providers in the timing of follow-up visits. Telephone Care Study Group.
OBJECTIVE: Although the decision about how frequently to see outpatients has a direct impact on a provider's workload and may impact health care costs, revisit intervals have rarely been a topic of investigation. To begin to understand what factors are correlated with this decision, we examined baseline data from a Department of Veterans Affairs (VA) Cooperative Study designed to evaluate telephone care. DESIGN: Observational study based on extensive patient data collected during enrollment into the randomized trial. Providers were required to recommend a revisit interval (e.g., "return visit in 3 months") for each patient before randomization, under the assumption that the patient would be receiving clinic visits as usual. POPULATION/SETTING: Five hundred seventy-one patients over age 55 cared for by one of the 30 providers working in three VA general medical clinics. Patients for whom immediate follow-up (</=2 weeks) was recommended were excluded. MEASUREMENTS: Mean revisit interval was adjusted for patient factors using a regression model that accounted for patients being nested within providers and providers being nested within sites. Four patient-level variable blocks (illness burden-patient, travel time, illness burden-physician, and prior utilization) were sequentially entered into a linear model to determine their role in explaining the variance in revisit intervals. Physician identity was also entered after four blocks. MAIN RESULTS: Recommended revisit intervals ranged from 1 month to over 1 year with the most common recommended intervals being 2, 3, or 6 months. About 10% of the variance in revisit interval was explained by illness measures independent of provider (e.g., general health perception) and travel time. Adding other illness measures (e.g., diagnoses, medications) and prior utilization (e.g., clinic visits) doubled the variance explained (R2 =.21). Finally, the identification of individual provider doubled the explained variance again (R2 =.45). After adjusting for patient factors, the average revisit interval for individual providers ranged from 8 to 26 weeks (8 to 19 weeks when restricted to the 16 staff physicians). There were also substantial differences across the three sites (adjusted means: 14, 17, and 11 weeks). CONCLUSIONS: Even after adjusting for a detailed array of patient-level data, primary care providers have different practice styles regarding the timing of return visits. These may, in turn, reflect the local "culture" in which they practice. How many patients providers are able to care for may be determined by the providers' inclinations toward the timing of follow-up visits.