Background: Supplier-induced demand (SID) refers to the concept that healthcare providers may deliver services that are not medically necessary to patients. An estimation of the extent to which this event has occurred can be insightful for policymaking and guiding health and insurance systems. This study aimed to investigate the extent of SID when performing a diagnostic ultrasonography for primary breast cancer patients and its relationship with socioeconomic factors in Iran.Methods: Data were obtained using questionnaires from 334 patients referred to the Cancer Research Center. To identify the patients who were candidates for undergoing a necessary diagnostic US, we employed the international clinical guidelines with confirmation of our expert panelists.With their assistance, a comprehensive index was created to screen those 'most probably affected by SID' .Results: 55.9% had undergone an unnecessary diagnostic ultrasonography, and thus were most probably affected by SID. A significant association between socioeconomic factors (education, occupation, and supplemental health insurance) and SID was confirmed (p value ≤ 0.001, 0.002, and 0.039, respectively).
Conclusion:This study supports the SID hypothesis and the unnecessary demand for diagnostic ultrasonography in