Rheumatology referral patterns.

The authors studied the characteristics of patients referred for rheumatology consultation in a group model HMO. Six hundred twelve patients were evaluated in 1986. The ages ranged from 3 to 85 years, with an average of 52 years. Female patients outnumbered male patients almost 3:1. Only 44% of referrals had a presumptive diagnosis and more than one half of these diagnoses were changed by the consulting rheumatology specialist, suggesting a high value added from the HMO rheumatologic consultation. Internists referred at a slightly higher rate than family practitioners, and pediatricians referred children at one tenth of the adult rate. Comparison with other published data on fee-for-service rheumatology practices indicates that in one group model HMO, which prohibits patient self-referral, rheumatologic specialists see a higher percentage of patients with vague or difficult-to-manage conditions such as the connective tissue diseases and fibromyalgia and a lower percentage of osteoarthritis and gout. This finding suggests that the structure and incentives of HMOs alter medical referral and practice patterns in significant ways.