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New ultrasound methods that can be used to quantitatively assess liver fat content have recently been developed. These quantitative ultrasound (QUS) methods are based on the analysis of radiofrequency echoes detected by the transducer, allowing calculation of parameters for quantifying the fat in the liver. In this position paper, after a section dedicated to the importance of quantifying liver steatosis in patients with non-alcoholic fatty liver disease and another section dedicated to the assessment of liver fat with magnetic resonance, the current clinical studies performed using QUS are summarized. These new methods include spectral-based techniques and techniques based on envelope statistics. The spectral-based techniques that have been used in clinical studies are those estimating the attenuation coefficient and those estimating the backscatter coefficient. Clinical studies that have used tools based on the envelope statistics of the backscattered ultrasound are those performed by using the acoustic structure quantification or other parameters derived from it, such as the normalized local variance, and that performed by estimating the speed of sound. Experts' opinions are reported.

Background To promote results in the National Lung Screening Trial (NLST) that are generalizable across the entire US population, a subset of NLST sites developed dedicated strategies for minority recruitment. Purpose To report the effects of targeted strategies on the accrual of underrepresented groups, to describe participant characteristics, and to estimate the costs of targeted enrollment. Methods The 2002–2004 Tobacco Use Supplement was used to estimate eligible proportions of racial and ethnic categories. Strategic planning included meetings/conferences with key stakeholders and minority organizations. Potential institutions were selected based upon regional racial/ethnic diversity and proven success in recruitment of underrepresented groups. Seven institutions submitted targeted recruitment strategies with budgets. Accrual by racial/ethnic category was tracked for each institution. Cost estimates were based on itemized receipts for minority strategies relative to minority accrual. Results Of 18,842 participants enrolled, 1576 (8.4%) were minority participants. The seven institutions with targeted recruitment strategies accounted for 1223 (77.6%) of all minority participants enrolled. While there was a significant increase in the rate of minority accrual pre-implementation to post-implementation for the institutions with targeted recruitment (9.3% vs. 15.2%, P<0.0001), there was no significant difference for the institutions without (3.5% vs. 3.8%, P=0.46). Minority enrollees at the seven institutions tended to have less than a high school education, be economically disadvantaged, and were more often uninsured. These socio-demographic differences persisted at the seven institutions even after adjusting for race and ethnicity. The success of different strategies varied by institution, and no one strategy was successful across all institutions. Costs for implementation were also highly variable, ranging from $146 to $749 per minority enrollee. Limitations Data on minority recruitment processes were not consistently kept at the individual institutions. In addition, participant responses via newspaper advertisements and the efforts of minority staff hired by the institutions could not be coded on Case Report Forms. Conclusions Strategic efforts were associated with significant increases in minority enrollment. The greatest successes require that a priori goals be established based on eligible racial/ethnic proportions; the historical performance of sites in minority accrual should factor into the selection of sites; recruitment planning must begin well in advance of trial launch; and there must be endorsement by prominent representatives of the racial groups of interest.

To prospectively validate predefined breast ultrasonographic (US) Breast Imaging Reporting and Data System (BI-RADS) category 3 criteria in a multicenter setting in an elevated-risk population. Materials and Methods: The American College of Radiology Imaging Network 6666 database was reviewed for prospectively defined BI-RADS category 3 lesions. Patient characteristics, lesion US features at initial detection, and work-up recommendations were analyzed with descriptive statistics. Exact 95% confidence intervals (CIs) were given, where appropriate. Lesion reference standard was biopsy or a minimum of 1-year follow-up. In addition, malignancy rate for lesions that had at least 2 years of follow-up data or that had biopsy data was calculated.