(469) Treatment preference, equipoise and expectations: what you expect is what you get

Abstract

Expected pain-relief from treatment is associated with positive clinical outcomes in patients with musculoskeletal pain. Less widely studied is the preference of the provider and patient for one type of treatment approach over others. The purpose of this study was to evaluate the extent to which these variables, the type of treatment received, and expectations for pain relief influenced pain intensity in an experimental model of low back pain. Healthy individuals were randomly assigned to receive manipulation (MAN), mobilization (MOB), or therapeutic touch (TT) 48 hours after an eccentric exercise protocol designed to induce acute low back pain. General linear modeling (GLM) was used to evaluate the contributions of expected pain relief, subject and provider treatment preference, and treatment received to pain relief immediately following MAN, MOB, or TT. Pain intensity was measured using the 101-point Numerical Pain Rating Scale. Data from 65 subjects (75.4% female, mean age 22.8) and 3 providers comprised the sample. No group differences existed in pre- and post-intervention pain intensity scores. Two providers expected SMT to provide the greatest pain relief and one did not have a preference. Twenty-four subjects (36.9%) had no treatment preference, four (6.2%) preferred MAN, 17 (26.2%) preferred MOB, and 20 (30.8%) preferred TT. GLM results indicated that subject expectation for pain relief significantly predicted pain relief (Waldχ2= 72.8, p<0.001). A significant interaction existed between treatment received and whether preference matched treatment; specifically, when a provider and subject had no preference about treatment, MAN was associated with pain relief (Waldχ2= 4.2, p=0.04). These data extend previous work related to expectations for pain relief to an acute model of low back pain. Our results suggest that an individual’s expectations for pain relief strongly predicted pain outcomes. Future work should extend these findings beyond the immediate time point.