title: Pioneer not-for-profit plans struggle to remain leaders.
authors.forename: B
authors.initials: B
authors.lastname: Carlson
mesh_terms: D002140:California; D019033:Delivery of Health Care, Integrated; D004465:Economic Competition; D006279:Health Maintenance Organizations / Q000458:organization & administration / Q000639:trends*; D006293:Health Promotion; D008389:Marketing of Health Services; D009511:New England; D009939:Organizations, Nonprofit / Q000639:trends*; D011315:Preventive Medicine; D014481:United States