Objective: To evaluate the real-world effectiveness of integrative medicine treatment on quality of life using the Patients Receiving Integrative Medicine Effectiveness Registry (PRIMIER).

Design: A prospective, longitudinal, observational evaluation of patient reported outcomes for quality of life.

Setting: Participants were patients from 17 integrative medicine clinics who received personalized, integrative medicine treatments between August 2013 and October 2017.

Main outcome measures: Participants completed the Patient Reported Outcomes Measurement Information System (PROMIS)- 29, Perceived Stress Scale-4 (PSS-4), and the Patient Activation Measure (PAM) at index (baseline) visit and at 2, 4, 6, and 12 month follow-up assessments. Electronic health record data included diagnostic and billing codes/descriptions. A linear mixed-effects model was used to test whether outcomes changed from index through 12 months RESULTS: During enrollment, 4883 participants began the assessment, 3658 completed the index measures, and 2374 (65 %) completed at least 1 follow-up assessment, had electronic health record data and at least 1 integrative medicine visit. Most participants (mean age=51.4 years) were white (88.4 %), female (79.7 %), and college-educated (78.5 %). Significant improvements (p < 0.001) were observed at 12-months on all PROMIS-29 measures, PSS-4, and PAM. At 12 months, clinically meaningful improvements were found for 38 % and 28 % on PROMIS-29 Mental and Physical Health Summary scores respectively.

Conclusions: PRIMIER is the largest study to assess the real-world effectiveness of integrative medicine. Results indicate a statistical and clinical improvement across all measures at 12 months. Future research could explore whether dosing, timing or combinations of integrative medicine interventions have differential impacts on quality of life.