Table 1 IDSRN partners and main collaborators

• The HMO Research Network, a longstanding network of research affiliates of large integrated and prepaid systems^a

• Denver Health, a large integrated safety net provider system

• Weill Medical College/New York Presbyterian, a large urban medical system

• Marshfield Clinic, a rural group practice (with Project Hope)

• United Healthcare, a major national health insurer (through their Center for Health Care Policy and Evaluation and a subcontract with RAND)

Led by others

• Abt Associates (with Geisinger Health Systems)

• Emory University's Center for Health Outcomes and Quality (originally based at Aetna, with whom it continued to collaborate)

• Research Triangle International (RTI) (with multiple provider systems)

• University of Minnesota's Division of Health Services Research and Policy (with Blue Cross Blue Shield of Minnesota, the Medical Group Management Association and others)