van Oldenrijk Jakob, Schafroth Matthias U, Bhandari Mohit, Runne Wouter C, Poolman Rudolf W
Department of Orthopaedic Surgery, Academic Medical Centre, Amsterdam, The Netherlands.
BMC Musculoskelet Disord. 2008 Jun 24;9:93. doi: 10.1186/1471-2474-9-93.
Two types of methods are used to assess learning curves: outcome assessment and process assessment. Outcome measures are usually dichotomous rare events like complication rates and survival or require an extensive follow-up and are therefore often inadequate to monitor individual learning curves. Time-action analysis (TAA) is a tool to objectively determine the level of efficiency of individual steps of a surgical procedure.
METHODS/DESIGN: We are currently using TAA to determine the number of cases needed for surgeons to reach proficiency with a new innovative hip implant prior to initiating a multicentre RCT. By analysing the unedited video recordings of the first 20 procedures of each surgeon the number and duration of the actions needed for a surgeon to achieve his goal and the efficiency of these actions is measured. We constructed a taxonomy or list of actions which together describe the complete surgical procedure. In the taxonomy we categorised the procedure in 5 different Goal Oriented Phases (GOP): 1. the incision phase. 2. the femoral phase. 3. the acetabulum phase. 4. the stem phase. 5. the closure pase. Each GOP was subdivided in Goal Oriented Actions (GOA) and each GOA is subdivided in Separate Actions (SA) thereby defining all the necessary actions to complete the procedure. We grouped the SAs into GOAs since it would not be feasible to measure each SA. Using the video recordings, the duration of each GOA was recorded as well as the amount of delay. Delay consists of repetitions, waiting and additional actions. The nett GOA time is the total GOA time - delay and is a representation of the level of difficulty of each procedure. Efficiency is the percentage of nett GOA time during each procedure.
This allows the construction of individual learning curves, assessment of the final skill level for each surgeon and comparison of different surgeons prior to participation in an RCT. We believe an objective and comparable assessment of skill level by process assessment can improve the value of a surgical RCT in situations where a learning curve is expected.
用于评估学习曲线的方法有两种：结果评估和过程评估。结果指标通常是二分法的罕见事件，如并发症发生率和生存率，或者需要广泛的随访，因此往往不足以监测个体学习曲线。时间动作分析（TAA）是一种客观确定外科手术各个步骤效率水平的工具。
方法/设计：我们目前正在使用TAA来确定外科医生在开展多中心随机对照试验之前熟练掌握一种新型创新髋关节植入物所需的病例数。通过分析每位外科医生前20例手术的未经编辑的视频记录，测量外科医生实现其目标所需的动作数量和持续时间以及这些动作的效率。我们构建了一个动作分类法或动作列表，共同描述整个手术过程。在分类法中，我们将手术过程分为5个不同的目标导向阶段（GOP）：1. 切口阶段。2. 股骨阶段。3. 髋臼阶段。4. 柄部阶段。5. 闭合阶段。每个GOP又细分为目标导向动作（GOA），每个GOA再细分为单独动作（SA），从而定义完成该手术所需的所有必要动作。由于测量每个SA不可行，我们将SA分组为GOA。使用视频记录，记录每个GOA的持续时间以及延迟量。延迟包括重复、等待和额外动作。净GOA时间是总GOA时间减去延迟，代表每个手术的难度水平。效率是每个手术中净GOA时间的百分比。
这使得能够构建个体学习曲线，评估每位外科医生的最终技能水平，并在参与随机对照试验之前比较不同的外科医生。我们认为，在预期存在学习曲线的情况下，通过过程评估对技能水平进行客观且可比较的评估可以提高外科随机对照试验的价值。
