Effectiveness of Ultrasound as a Triage Tool in Ruling out Fractures among Non-Critical Emergency Department Patients

The popularity of ultrasound for acute diagnosis of fractures in the Emergency Department (ED) has increased over the recent years. This present study aimed to determine the sensitivity and specificity of ultrasound use for detection of fractures in a different environment, which is at the triage area of the ED. We compared the results of bedside ultrasound in detecting non-critical fractures to the current gold standard of X-rays in the triage area. The design was a single centered crosssectional study. From August 2014 till November 2014, a total of 46 patients were recruited, creating 75 image pairs. Following consent, a bedside ultrasound was performed and subsequently compared with X-ray reporting regarding the presence or absence of fractures. SPSS analysis was used to determine the sensitivity and specificity of ultrasound in diagnosing fracture as compared to X-rays. Ultrasound had a sensitivity of 72% (95% CI, 50.6% - 87.9%) and a specificity of 80% (95%CI: 66.3 – 90%) when compared to X-rays in fracture diagnosis. The kappa analyses showed moderate inter observer agreement (0.5) between ultrasound and X-rays in diagnosing fractures. This study suggests that the use of ultrasound as a triage tool yet has unacceptable sensitivity and needs further evaluation and consideration.

Method comparison studies in medicine

Most of important variables measured in medicine are in numerical forms or continuous in nature. New instruments and tests are constantly being developed for the purpose of measuring various variables, with the aim of providing cheaper, non-invasive, more convenient and safe methods. When a new method of measurement or instrument is invented, the quality of the instrument has to be assessed. Agreement and reliability are both important parameters in determining the quality of an instrument. This article will discuss some issues related to methods comparison study in medicine for the benefit of medical professional and researcher. METHOD: This is a narrative review and this article review the most common statistical methods used to assess agreement and reliability of medical instruments that measure the same continuous outcome. The two methods discussed in detail were the Bland-Altman Limits of Agreement, and Intra-class Correlation Coefficient (ICC). This article also discussed some issues related to method comparison studies including the application of inappropriate statistical methods, multiple statistical methods, and the strengths and weaknesses of each method. The importance of appropriate statistical method in the analysis of agreement and reliability in medicine is also highlighted in this article. CONCLUSION: There is no single perfect method to assess agreement and reliability; however researchers should be aware of the inappropriate methods that they should avoid when analysing data in method comparison studies. Inappropriate analysis will lead to invalid conclusions and thus validated instrument might not be accurate or reliable. Consequently this will affect the quality of care given to a patient.