From the CRICO/Risk Management Foundation of the Harvard Medical Institutions.
J Patient Saf. 2021 Dec 1;17(8):e995-e1000. doi: 10.1097/PTS.0000000000000706.
The relationship between medical malpractice risk and one of the fundamental characteristics of physician practice, clinical volume, remains undefined. This study examined how the annual and per-patient encounter medical malpractice claims risk varies with clinical volume.
Clinical volume was determined using health insurance charges and was linked at the physician level to malpractice claims data from a malpractice insurer. The annual medical malpractice claims risk was expressed as the percent of physicians with a malpractice claim, and the per-encounter medical malpractice claims risk was expressed as malpractice claims per 1000 patient encounters. Both of these malpractice claims risk metrics were analyzed as a function of clinical volume, using linear and spline regression.
As clinical volume increased, the percent of physicians with a malpractice claim increased linearly. Among all physicians studied, for each decile increase in clinical volume, there was a 0.373% increase in physicians with a malpractice claim (95% confidence interval, 0.301%-0.446%; P < 0.0001). As clinical volume increased, the rate of malpractice claims per 1000 patient encounters decreased. This relationship between clinical volume and per-encounter claims risk was nonlinear. There was a clinical volume threshold, below which decreasing clinical volume was associated with increasing per-encounter claims risk, and above which claims risk no longer significantly varied with increases in clinical volume.
Clinical volume is a crucial determinant of physician malpractice risk, with higher-volume physicians having higher annual risk but lower per-encounter risk. Clinical volume data should be incorporated into analyses of malpractice risk.
医疗事故风险与医师执业的一个基本特征（即临床量）之间的关系尚未明确。本研究旨在探讨年度和每位患者就诊的医疗事故索赔风险随临床量的变化情况。
临床量通过医疗保险收费确定，并在医师层面上与医疗事故保险公司的医疗事故索赔数据相关联。年度医疗事故索赔风险表示有索赔的医师比例，每位就诊患者的医疗事故索赔风险表示每 1000 名患者就诊的索赔数量。这两种医疗事故索赔风险指标都通过线性和样条回归分析与临床量相关。
随着临床量的增加，有医疗事故索赔的医师比例呈线性增加。在所研究的所有医师中，临床量每增加一个十分位数，有医疗事故索赔的医师比例增加 0.373%（95%置信区间，0.301%-0.446%；P<0.0001）。随着临床量的增加，每位就诊患者的索赔率降低。临床量与每位就诊患者索赔风险之间的关系是非线性的。存在一个临床量阈值，低于该阈值，临床量减少与每位就诊患者索赔风险增加相关，而高于该阈值，索赔风险不再随临床量的增加而显著变化。
临床量是医师医疗事故风险的关键决定因素，高临床量的医师具有更高的年度风险，但每位就诊患者的风险较低。临床量数据应纳入医疗事故风险分析中。
