Practice patterns in spine radiograph utilization among doctors of chiropractic enrolled in a provider network offering complementary care in the United States.

OBJECTIVE: Nonspecific back pain is associated with high use of diagnostic imaging in primary care, yet current evidence suggests that routine imaging of the spine is unnecessary. The objective of this study is to describe current practice patterns in spine radiograph utilization among doctors of chiropractic enrolled in an American provider network. METHODS: A cross-sectional analysis of administrative claims data from one of the largest providers of complementary health care networks for health plans in the United States was performed. Survey data containing provider demographics were linked with routinely collected data on spine radiograph utilization and patient characteristics aggregated at the provider level. We calculated rates and variations of spine radiographs over 12 months. Negative binomial regression was performed to identify significant predictors of high radiograph utilization and to estimate the associated incidence risk ratio. RESULTS: Complete data for 6946 doctors of chiropractic and 249193 adult patients were available for analyses. In 2010, claims were paid for a total of 91542 new patient examinations and 23369 spine radiographs (including 17511 ordered within 5 days of initial patient examination). The rate of spine radiographs within 5 days of an initial patient visit was 204 per 1000 new patient examinations. Significant predictors of higher radiograph utilization rates included the following: practicing in the Midwest or South US census regions, practicing in an urban or suburban setting, chiropractic school attended, and being a male provider in full-time practice with more than 20 years of experience. CONCLUSION: Chiropractic school attended and practice location were the most influential predictors of spine radiograph utilization among network chiropractors. This information may help to inform the development and evaluation of a tailored intervention to address overuse of radiograph utilization.

Impact of imaging guidelines on X-ray use among American provider network chiropractors: interrupted time series analysis.

BACKGROUND CONTEXT: Overuse and misuse of spine X-ray imaging for nonspecific back and neck pain persists among chiropractors. Distribution of educational materials among physicians results in small-to-modest improvements in appropriate care, such as ordering spine X-ray studies, but little is known about its impact among North American chiropractors. PURPOSE: To evaluate the impact of web-based dissemination of a diagnostic imaging guideline on the use of spine X-ray images among chiropractors. STUDY DESIGN/SETTING: Quasi-experimental design that used interrupted time series to evaluate the effect of guidelines dissemination on spine X-ray imaging claims by chiropractors enlisted in managed care network in the United States. PATIENT SAMPLE: Consecutive adult patients consulting for complaints of spine disorders. OUTCOME MEASURES: A change in level (the mean number of spine X-ray imaging claims per month immediately after the introduction of the guidelines), change in trend (any differences between preintervention and postintervention slopes), estimation of monthly average intervention effect after the intervention. METHODS: The imaging guideline was disseminated online in April 2008. Administrative claims data were extracted between January 2006 and December 2010. Segmented regression analysis with autoregressive error was used to estimate the impact of guideline recommendations on the rate of spine X-ray studies. Sensitivity analysis considered the effect of two additional quality improvement strategies, a policy change and an education intervention. RESULTS: Time series analysis revealed a significant change in the level of spine X-ray study ordering weeks after introduction of the guidelines (-0.01; 95% confidence interval=-0.01, -0.002; p=.01), but no change in trend of the regression lines. The monthly mean rate of spine X-ray studies within 5 days of initial visit per new patient exams decreased by 10 per 1000, a 5.26% relative decrease after guideline dissemination. Controlling for two quality improvement strategies did not change the results. CONCLUSIONS: Web-based guideline dissemination was associated with an immediate reduction in spine X-ray imaging claims. Sensitivity analysis suggests our results are robust. This passive strategy is likely cost-effective in a chiropractic network setting.