A common question in sports injury research is ‘what proportion of athletes sustained an injury over a certain time period?’. In cross-sectional studies, where data are collected at a single point in time, the prevalence proportion is simply the number of injured athletes divided by the total sample. In prospective cohort studies, caution is needed as the injury incidence proportion (proportion of newly injured athletes during the observation period) is likely to be underestimated by simply using the approach that is valid for cross-sectional studies. As a part of the BJSM methods matter series,1 we here compare the analytical approaches for cross-sectional studies and prospective cohort studies (ie, without censoring and with censoring, respectively) to help the reader accurately estimate incidence proportion in prospective studies. To describe the proportion of sports injuries occurring over a given time period, one can calculate the CIP. The CIP can be calculated with or without censoring (in this paper, we discuss the concept of ‘right censoring’, but use the term ‘censoring’ only). For instance, the number of injured runners in a 1-year prospective cohort study was 252 of 931.2 Hence, the CIP calculated without censoring is 27% …

中文翻译：

---

在前瞻性研究中受伤的运动员比例是多少？审查意见很重要

运动损伤研究中的一个常见问题是“在特定时间段内受伤的运动员比例是多少？”。在横断面研究中，数据是在单个时间点收集的，患病率只是受伤运动员人数除以总样本。在前瞻性队列研究中，需要谨慎，因为仅使用对横断面研究有效的方法可能会低估损伤发生率（观察期内新受伤运动员的比例）。作为 BJSM 方法问题系列的一部分，1 我们在这里比较了横断面研究和前瞻性队列研究的分析方法（即分别没有删失和删失），以帮助读者准确估计前瞻性研究中的发生率。为了描述在给定时间段内发生的运动损伤的比例，可以计算 CIP。CIP 可以在有或没有审查的情况下计算（在本文中，我们讨论“右审查”的概念，但仅使用术语“审查”）。例如，在一项为期 1 年的前瞻性队列研究中受伤的跑步者人数是 931.2 人中的 252 人因此，未经审查计算出的 CIP 为 27%……