Using zero-inflated models to explain chronic illness, pain, and complementary and alternative medicine use

Objective: To extend knowledge of complementary and alternative medicine (CAM) use by understanding how poor health influences both trying CAM and number of CAM types used. Methods: Using the 2002 National Health Interview Survey's Supplemental Section, zero-inflated models were employed to examine CAM use across 5 domains. Results: Results indicate that level of pain is the only consistent predictor of both the likelihood of trying CAM and how many types of CAM are used. Pain increased the odds ratio and number of CAM types used across all domains. Findings, however, were mixed for health status and chronic conditions. Only prayer was associated with higher odds ratio (OR=1.705, P<.001) and number of CAM types used for chronic illnesses (OR=1.024, P<.01). Conclusions: Expanding to zero-inflated models demonstrates variation in CAM use behaviors. Pain is the only consistent predictor of both trying CAM and the number of CAM types used. Chronic illness is only consistently influential for prayer.