Biostatistics and Medical Informatics Department, Faculty of Medicine, University of Porto, Porto, Portugal.
J Clin Epidemiol. 2011 Mar;64(3):264-9. doi: 10.1016/j.jclinepi.2009.11.010. Epub 2010 Mar 1.
To compare the interpretation of agreement in the prediction of neonatal outcome variables, using the limits of agreement (LA) and the intraclass correlation coefficient (ICC).
Three obstetricians were asked to predict neonatal outcomes independently based on the evaluation of intrapartum cardiotocographic tracings. Interobserver agreement was assessed with the LA and the ICC, and the results obtained were interpreted by six clinicians and six statisticians on a scale that established agreement as very poor, poor, fair, good, or very good.
Interpretation of the LA results was less consensual than the ICC results, with proportions of agreement of 0.36 (95% confidence interval [CI]: 0.28-0.44) vs. 0.63 (95% CI: 0.54-0.73), respectively. LA results suggested a fair to good agreement among obstetricians, whereas interpretation of ICC results suggested a poor to fair agreement. LA results were more plausible with reality, suggesting that obstetricians predicted neonatal outcomes better than randomly generated values, whereas it was not always the case with the ICC.
LA and ICC can provide inconsistent results in agreement studies. Accordingly, in the absence of better strategies to assess agreement, both should be used for this purpose, but their results need to be interpreted with caution keeping their respective limitations in mind.
比较使用界限协议（LA）和组内相关系数（ICC）来解释预测新生儿结局变量的一致性。
要求三位产科医生独立根据产时胎心监护图的评估来预测新生儿结局。使用 LA 和 ICC 评估观察者间一致性，由六位临床医生和六位统计学家对结果进行解释，将一致性分为非常差、差、一般、好或非常好。
LA 结果的解释不如 ICC 结果一致，其一致比例分别为 0.36（95%置信区间 [CI]：0.28-0.44）和 0.63（95% CI：0.54-0.73）。LA 结果表明产科医生之间的一致性为一般到良好，而 ICC 结果的解释则表明一致性为差到一般。LA 结果与现实更相符，表明产科医生预测新生儿结局的能力优于随机生成的值，而 ICC 则并非总是如此。
LA 和 ICC 在一致性研究中可能会提供不一致的结果。因此，在没有更好的评估一致性的策略的情况下，都可以用于此目的，但需要谨慎解释其结果，并牢记各自的局限性。
