Congenital absence of bilateral ulnar arteries in a symptomatic adult patient

Abstract

off value for MCID of PRWE was 18, and the value of MDC of PRWE was 13. The sensitivity of this cut-off value was 61%, and the specificity was 100%. Two approaches are usually used to determine the MCID. One is the anchor-based approach, and the other is the distribution-based approach. However, there are various types of calculation methods in both approaches, which is a limitation of the MCID. We chose the ‘global ratings of change’ method, which is one of the most commonly used anchorbased approaches for establishing the MCID in longitudinal studies. Even though the retrospective ratings are susceptible to recall bias and the anchor-based approach does not consider the measurement precision, it is easy to obtain and provides the single best measure of the significance of change from the individual’s perspective. To compensate for the limitation of the anchor-based approach and define clinically meaningful change, use of multiple methods is strongly advocated. The distributionbased approaches, particularly those based on measurement precision, are best suited for the purpose of establishing that any observed changes are beyond the range of the measurement error of the instrument. It cannot be expected that the anchor-based and distribution-based approaches will be equivalent in all circumstances. Therefore, it is essential that the integrated system provides a means for resolving discrepancies across the method, and we used MDC methods as reference standard to determine the MCIDs of both PRO instruments. As the number of exclusions due to incomplete data and poor reliability was substantial and not every patient did have a minimum of two DASH and two PRWE scores, our results should be accepted with caution. Our study suggests that the MCIDs of DASH and PRWE were 9 and 18, respectively; and when the DASH and PRWE are used to measure subjective outcomes, the MCID of DASH is more sensitive and the MCID of PRWE is more specific in detecting clinical changes after surgical treatment of distal radial fractures.