title: Reliable and valid assessment of point-of-care ultrasonography.
abstract: OBJECTIVE
  To explore the reliability and validity of the Objective Structured Assessment of Ultrasound Skills (OSAUS) scale for point-of-care ultrasonography (POC US) performance.
  
  
  BACKGROUND
  POC US is increasingly used by clinicians and is an essential part of the management of acute surgical conditions. However, the quality of performance is highly operator-dependent. Therefore, reliable and valid assessment of trainees' ultrasonography competence is needed to ensure patient safety.
  
  
  METHODS
  Twenty-four physicians, representing novices, intermediates, and experts in POC US, scanned 4 different surgical patient cases in a controlled set-up. All ultrasound examinations were video-recorded and assessed by 2 blinded radiologists using OSAUS. Reliability was examined using generalizability theory. Construct validity was examined by comparing performance scores between the groups and by correlating physicians' OSAUS scores with diagnostic accuracy.
  
  
  RESULTS
  The generalizability coefficient was high (0.81) and a D-study demonstrated that 1 assessor and 5 cases would result in similar reliability. The construct validity of the OSAUS scale was supported by a significant difference in the mean scores between the novice group (17.0; SD 8.4) and the intermediate group (30.0; SD 10.1), P = 0.007, as well as between the intermediate group and the expert group (72.9; SD 4.4), P = 0.04, and by a high correlation between OSAUS scores and diagnostic accuracy (Spearman ρ correlation coefficient = 0.76; P < 0.001).
  
  
  CONCLUSIONS
  This study demonstrates high reliability as well as evidence of construct validity of the OSAUS scale for assessment of POC US competence. Hence, the OSAUS scale may be suitable for both in-training as well as end-of-training assessment.
authors: *Centre for Clinical Education, University of Copenhagen, and The Capital Region of Denmark †Juliane Marie Centre, Copenhagen University Hospital Rigshospitalet, Denmark ‡Department of Radiology, Copenhagen University Hospital Hvidovre, Denmark §Department of Radiology, Ultrasound Section, Diagnostic Centre, Copenhagen University Hospital Rigshospitalet, Denmark ¶Department of Surgery, Abdominal Centre, Copenhagen University Hospital Rigshospitalet, Denmark; and ‖Department of Anesthesia and The Wilson Centre, University of Toronto, and The University Health Network, Toronto, Canada.
authors: Tobias
authors: T
authors: Todsen
authors: Martin Grønnebæk
authors: MG
authors: Tolsgaard
authors: Beth Härstedt
authors: BH
authors: Olsen
authors: Birthe Merete
authors: BM
authors: Henriksen
authors: Jens Georg
authors: JG
authors: Hillingsø
authors: Lars
authors: L
authors: Konge
authors: Morten Lind
authors: ML
authors: Jensen
authors: Charlotte
authors: C
authors: Ringsted
mesh_terms: D000005:Abdomen / Q000000981:diagnostic imaging*; D002983:Clinical Competence; D006801:Humans; D019095:Point-of-Care Systems / Q000592:standards*; D015203:Reproducibility of Results; D016037:Single-Blind Method; D014463:Ultrasonography / Q000592:standards*; D014741:Video Recording