Final answer:
The Health Maintenance Organization (HMO) insurance plan model requires a referral from a primary care provider to see a dermatologist or other specialists.
Step-by-step explanation:
The insurance plan model that requires a referral from a primary care provider to schedule an appointment with a specialist such as a dermatologist is known as a Health Maintenance Organization (HMO). HMOs often require patients to select a primary care physician (PCP) who becomes the main point of contact for all health concerns. To see a specialist, the PCP must determine that a specialist's care is necessary, and they will provide a referral to a dermatologist within the network. This gatekeeper approach is designed to control costs and ensure that specialist care is used appropriately.
In this model, the primary care provider serves as a gatekeeper to specialty care, such as dermatology. The referral is necessary to ensure that the visit to the dermatologist is medically necessary and appropriate.