Francisco Rheumatoid Arthritis Panel for differences in the use of specific antirheumatic treatments, especially anti-tumor necrosis factor (anti-TNF) agents, among patients in health maintenance organizations (HMOs), other managed care health plans (preferred provider organizations or point of service plans), and fee-for-service plans (Yelin EH, Trupin LS, Katz PP. Impact of managed care on the use of biologic agents for rheumatoid arthritis. Arthritis Rheum 2005;53: 423-30). The authors have been following these patients since 1982-1983 using annual telephone interviews. Their data now includes an impressive 11,669 person-years of observation, although there has unfortunately been an ฯณ65% attrition (ฯณ25% died, ฯณ30% declined participation, and ฯณ10% were lost to followup). There also appears to be an ฯณ20% turnover during each year, with 6 -10% patients starting and 8 -10% stopping anti-TNF agents, for example.
This study has significant strengths, such as a long-term followup and a clear and thorough analysis, which the authors achieved by attempting to account for the abovementioned turnover. It also has some weaknesses, including the very significant attrition, the fact that all followups are by telephone interview (introducing memory biases), and the fact that one of the major control groups (the fee-for-service group) comprises only 92 patients. Taking into consideration these weaknesses, the authors point out that allocation of certain medications differs between patients in HMOs, other managed care plans, and fee-forservice plans; namely, patients in HMOs use fewer biologic agents or cyclooxygenase 2 inhibitors than patients in fee-for-service plans and are less likely than patients in other managed care plans to start taking biologic agents. This implies that this difference is the result of a bottomline orientation (i.e., the agents are expensive and there-