In which model are contracted health services delivered to subscribers by physicians who remain in their independent office settings?

The correct answer pertains to the Independent Practice Association (IPA) model in healthcare. In an IPA model, contracted health services are indeed delivered to subscribers by physicians who operate in their own independent office settings. This structure allows physicians the flexibility to maintain their private practices while participating in a managed care organization.

IPAs negotiate contracts with health plans or insurers to provide healthcare services to members. By doing so, physicians can retain their autonomy and continue serving their patient base in their established settings, while patients benefit from the arrangements made by the IPA, such as access to a network of providers and potentially lower costs due to negotiated rates.

The other models mentioned, while they may offer various advantages or organizational structures, do not specifically operate in the same manner as an IPA. For example, an Integrated Delivery System (IDS) combines various healthcare services and providers under a single organizational umbrella, which may not allow for the same level of independence for physicians. Therefore, in the IPA model, the distinctive feature is the independent practice of physicians who serve enrolled patients while being part of a larger network.