Clinical, Demographic, and Geographic Determinants of Variation in Chiropractic Episodes of Care for Adults Using the 2005-2008 Medical Expenditure Panel Survey

ObjectiveThe primary aim of this study was to report nationally representative estimates of the visit utilization, per visit expenditures, and total expenditures for chiropractic episodes of care in the US adult population. The secondary aim was to identify clinical, demographic, geographic, and payment factors associated with variation in the levels of utilization and expenditures.MethodsData from the 2005-2008 Medical Expenditure Panel Survey were used to construct complete episodes of chiropractic care (n = 1639) for the civilian, noninstitutionalized adult population. Bivariate descriptive statistics were calculated for visit utilization, per visit expenditures, and total expenditures per episode of care by several clinical, demographic, geographic, and payment variables. Multivariable regression models were used to evaluate the effects of the independent variables on each of the 3 dependent variables.ResultsThe unadjusted mean number of visits per episode was 5.8 (95% confidence interval [CI], 5.3-6.4] and varied significantly by race/ethnicity, perceived mental health, urban-rural location, and source of payment. The mean total expenditures per visit per episode were estimated to be $69 (95% CI, $65-$73). There was variation associated with the census region, urban-rural location, and source of payment variables. Total expenditures for an episode of care were estimated to be $424 (95% CI, $371-$477] with variation according to urban-rural location and source of payment. During 29% of the episodes all expenditures were paid with out-of-pocket funds.ConclusionsVariation in the utilization and expenditures during chiropractic episodes of care is primarily associated with payment source and geographic factors.