Objectives. This study estimated the frequency of ultrasounds ordered for clinically obvious inguinal hernias in patients referred to surgeons and evaluated the clinical value of ultrasonography for this patient population. Methods. The present study was a prospective diagnostic and therapeutic impact study conducted in district, rural and tertiary referral hospitals in Sydney, Hawkesbury and Wagga Wagga, Australia. The study included adult patients (廍18 years of age) who had been referred to one of the participating surgeons for an elective inguinal hernia repair. The study determined the proportion of: (1) patients who underwent an inguinal hernia repair for a clinically obvious hernia and also had an ultrasound; (2) ultrasounds ordered by general practitioners (GPs); and (3) these ultrasounds that altered diagnosis and consequent surgical management from the surgeon's perspective. Results. In all, 144 participants were included in this study. Of these patients, 134 had a clinically apparent inguinal hernia on physical examination, and 63 of 133 patients (47%; 95% confidence interval (CI) 39-56%) underwent an ultrasound (information was missing for one patient). Overall 68 ultrasounds were ordered, with 63 ordered by GPs. Following the ultrasound, surgeons reported that one patient (1%; 95% CI 0-8 patients) had an altered diagnosis, and five patients (8%; 95% CI 3-17 patients) had altered management. Conclusion. This study found that almost one in two patients referred to a surgeon with a clinically obvious inguinal hernia also underwent a groin ultrasound. These studies represent an unnecessary waste of limited healthcare resources and low-value medical care because they rarely affect the final diagnosis or surgical management. [ABSTRACT FROM AUTHOR]