Kaerlev Linda, Lynge Elsebeth, Sabroe Svend, Olsen Jorn
Department of Epidemiology and Social Medicine, University of Aarhus, Vennelyst Boulevard 6, DK-8000 Aarhus C, Denmark.
Am J Ind Med. 2003 Sep;44(3):298-303. doi: 10.1002/ajim.10266.
Use of surrogate responders often needs to be considered in case-control studies with a high case fatality.
Agreement between 98 colon cancer patients and their closest relative was expressed as a percentage of the exact agreement and by Kappa coefficients and intra-class correlation coefficients.
The percentage of "don't know" answers was higher for surrogates than for index cases and the highest percentage was seen for questions on early events like childhood diseases. Agreement was best for responses to dichotomous questions on smoking and for prevalent or chronic diseases like diabetes or psoriasis, and lower (54-64%) when a quantitative response of, e.g., smoking was requested. The next-of-kin reported fewer job periods than the study person, 4.5 and 2.8, respectively, and there was a higher agreement for the latest job held than for the longest held job. We found an overall agreement between 91% and 100% for responses to ever having worked in a specific type of industry or occupation.
Use of next-of-kin data will often be a better alternative than excluding severely ill or deceased cases, if the exposure under study correlates with disease progression.
在病死率较高的病例对照研究中，通常需要考虑使用替代应答者。
98名结肠癌患者与其近亲之间的一致性通过精确一致性百分比、卡帕系数和组内相关系数来表示。
替代者“不知道”答案的百分比高于索引病例，对于诸如儿童疾病等早期事件的问题，该百分比最高。对于关于吸烟的二分问题以及糖尿病或牛皮癣等流行或慢性疾病的回答，一致性最佳；当要求对例如吸烟进行定量回答时，一致性较低（54% - 64%）。近亲报告的工作时间段比研究对象少，分别为4.5个和2.8个，对于最近从事的工作的一致性高于对于从事时间最长的工作的一致性。我们发现，对于是否曾在特定类型的行业或职业工作过的回答，总体一致性在91%至100%之间。
如果所研究的暴露与疾病进展相关，那么使用近亲数据通常比排除重症或死亡病例是更好的选择。
