Background: Persons insured by AOK Nordost statutory health insurance (SHI) and on sick leave underwent a 20-day program of interdisciplinary multimodal pain therapy (IMST) following an initial assessment (IA). We evaluated its effectiveness regarding sick leave, utilization/costs of SHI services, and patient-reported characteristics of pain., Materials and Methods: Participants with >14 days of IMST in 2013-2015 and with data necessary for comparison (intervention group, IG) were matched 1:1 in 2 steps. From AOK Nordost data, we identified a comparison group (CG) having characteristics matching exactly and by propensity score. Starting on the IA (IG) or a comparable reference day (CG), we analyzed utilization/costs of services related to back pain for 365 days. Participants' characteristics of pain were surveyed on the IA day and within 183-365 days., Results: The 86 IG patients had on average 44.33 (median 12) days of sick leave less than the CG after their initial sick leave starting at the IA (significant, p <0.05). Fewer IG patients had ≥1 hospitalization (OR 0.33; 95%CI 0.12-0.88), ≥1 prescription of physiotherapy (OR 0.35; 95%CI 0.24-0.82), and ≥1 specialist visit (OR 0.39; 95%CI 0.10-0.52) related to back pain. More IG patients had "lasting absence of treatment" (OR 4.06; 95%CI 1.09-15.1). Follow-up interviews were available for 56 IG patients, showing less pain intensity, impairment by pain, and pain severity (significant). Regarding the SHI perspective, cost savings per patient nearly covered the IA and IMST costs., Discussion: For a selected comparable population treated by protocol, IA and IMST was associated with reduction or "lasting absence" of treatment, pain relief, and major savings on sickness benefits. Other than in previous studies we found coverage of IA and IMST costs without consideration of productivity loss.