Development and Validation of Metrics Lumbar Labor Epidural Catheter Placement

Study part 1 After ethics committee approval a group of experts (n = 3 ) in conventional lumbar epidural catheter placement will be selected (an expert is defined as one who has performed more than 500 labor epidurals in preceding 5 year period). During a number of face-to-face meetings experts will identify, characterize and define the procedure. They will analyze task and identify units of behavior to be measured which constitute in a step-wise fashion how the procedure is optimally performed and deviations from optimal procedure performance as described previously. After informed consent from the patient and the anaesthetist performing the procedure, 2 video recordings of experts performing epidural and 2 video recordings of novices (defined as one who has done less than 50 epidurals) performing epidural will be recorded for detailed review during metric development meetings.

Study part 2 The developed metrics will be subjected to assessments of construct validity (a set of procedures for evaluating a testing instrument based on a degree to which the test terms identify the quality, ability or trait it was designed to measure) and concurrent validity (the evaluation in which the relationship between the test scores and the scores on the another instrument purporting to measure the same construct are related). We will also evaluated the inter-rater reliability of the metrics using i) proportion of agreement between raters, ii) correlation strength (using Pearson's Correlation Coefficient) and iii) Coefficient Alpha. After informed consent,10 experts (who are not a part of committee developing the metrics) each performing one or more lumbar epidural catheter placements for labor and 10 novices each performing one or more lumbar epidural catheter placements for labor will be video recorded. Two experts will review the video recording and score the performance based on checklist based system developed and compare with likert-scale checklists/global rating scale system.