The state of Ohio Monday launches a formal effort to shift the health care industry's business model from one based on volume to one based on value. When the state's Medicaid program rebids contracts this year for 2013, it will base a greater portion of its payments to managed care plans such as Dayton-based CareSource on how effectively patients are treated. The Medicaid program also will require that managed care plans develop incentives for health care providers to improve enrollees' health.