in Iran, physicians are both overseers and decision-makers, putting their own interests ahead of patients (Keyvanara et al.,2014). Models of demand for health care that do not explicitly take into account supplier behavior are regarded poorly defined as long as the physician's economic position has an impact on the level and direction of influence exerted. Evans (1974) discovered 24 subthemes or aspects, which were subsequently classified into four categories: health-care system, insurer, health-care provider, and health-care recipient themes. Poor monitoring and control, the fee-for-service payment system, insurance companies' limited role, insufficient monitoring of insurance companies, the educational nature of our health centers, health-care providers' interests, and the information gap that exists between patients and providers were all significant factors in the induced demand for health-care services in the United States. By researching the elements that influence supplier-induced demand, health policymakers and management can design methods to lower induced demand for health care. Monitoring and control, FFS payment system, medical guidelines and protocols, weak health information technology systems, ineffective referral system, dysfunctional tax system, educational nature of health centers, and health policy were mentioned by interviewees as factors in induced demand for health care (Evans, 1974). Inadequate monitoring is one of the most critical variables impacting induced demand. The most important factor in induced demand is an intermediary between the giver and the recipient. When physicians and patients have differing levels of expertise, there is an incentive to create demand. The problem will endure because no one is filling the informational hole. Another factor that contributes to demand is the educational nature of our health facilities. Some facilities, for example, perform duplicate CT scans or angiographies for students to see. One of the reasons of induced demand is a flawed health-care tax structure. A progressive tax can aid in the prevention of induced demand. Of course, there must be some form of regulation to prevent doctors from selecting easy patients and rejecting difficult ones (Evans, 1974) See also Direct-to-consumer advertising Health economics Induced demand Information asymmetry Principal–agent problem Market failure Moral hazard References Evans, R.G. (1974). Supplier-Induced Demand: Some Empirical Evidence and Implications. In: Perlman, M. (eds) The Economics of Health and Medical Care. International Economic Association Series. Palgrave Macmillan, London. https://doi.org/10.1007/978-1-349-63660-0_10 Demand Health economics