What are the major differences between HMO staff, group, and network models?

HMO staff model: HMO entity owns the facilities and employs the health care providers. Health care providers are paid a fixed salary, and any profits go directly to the HMO.
Group model HMO: operates on a contractual basis with health care provider medical groups and facilities that provide services to members.
Network model HMO: contracts with more than one physician group, hospital, and other facilities to provide a comprehensive health care package. Health care providers may share in some of the profit or loss of the HMO according to contract terms but are not required to provide care only to the patients of a specific HMO.