Measurement of endometrial thickness at US in multicenter drug trials: Value of central quality assurance reading

PURPOSE: To assess the value of central quality assurance (QA) reading of t ransvaginal ultrasonographic (US) images obtained to measure endometrial th ickness and to assess image quality. MATERIALS AND METHODS: Results of 2,000 US examinations performed in 1,000 subjects during one of two multicenter drug trials were evaluated. Endometr ial thickness was measured at the study site; images were then sent to the QA center, where an experienced sonologist evaluated endometrial thickness and image quality. RESULTS: In 360 (18%) of the 2,000 examinations, image quality was insuffic ient for central QA reading. Repeat examinations were requested, and sugges tions for improvement in technique were provided. In 349 (97%) of the 360 e xaminations, repeat US images were of acceptable quality. In 99 (5%) of the 1,989 examinations in which endometrial thickness was measured, central me asurement of thickness differed by more than 2 mm from that of the site. In a group (n = 300) that was followed up for 1 year, requests for repeat US examinations decreased from 24% at baseline to 11% at 1 year. CONCLUSION: Central QA reading provides a consistent evaluation of endometr ial thickness on US images obtained in multicenter drug trials and helps to ensure the acquisition of high-quality transvaginal US images. It further leads to demonstrable improvement in site performance.