Aitken J F, Green A, MacLennan R, Jackman L, Martin N G
Queensland Institute of Medical Research, Brisbane, Australia.
Br J Cancer. 1993 May;67(5):1036-41. doi: 10.1038/bjc.1993.190.
Surrogate reports by patients about their relatives, and vice versa, are potentially of great use in studies of the genetic and environmental causes of the familial aggregation of cancer. To assess the quality of such information in a family study of melanoma aetiology in Queensland, Australia, the authors compared surrogate reports with self-reports of standard melanoma risk factors obtained by mailed self-administered questionnaire. There was moderate agreement between surrogate reports provided by the cases and relatives' self-reports for questions on ability to tan (polychoric correlation coefficient (pc) = 0.60), skin colour (pc = 0.57), average propensity to burn (pc = 0.56), and hair colour at age 21 (kappa coefficient = 0.55), although relatives in the extreme risk factor categories were misclassified by surrogates at least half of the time. Agreement was lower for questions on degree of moliness (pc = 0.45), tendency to acute sunburn (pc = 0.42), and number of episodes of painful sunburn (pc = 0.23). The quality of relatives' surrogate reports about cases was similar to that of cases' surrogate reports about relatives. Cases who reported a family history of melanoma provided better surrogate information than did cases who indicated no family history, and female cases provided better surrogate reports than did males. Cases were better able to report for their parents and children than for their siblings. The authors conclude that when the use of surrogate reports of melanoma risk factors is unavoidable, results should be interpreted cautiously in the light of potentially high rates of misclassification. In particular, surrogate reports appear to be a comparatively poor measure of self-assessment of number of moles, the strongest known phenotypic indicator of melanoma risk, and may bias comparisons between families with and without a history of melanoma.
患者关于其亲属的替代报告，以及亲属关于患者的替代报告，在癌症家族聚集的遗传和环境病因研究中可能非常有用。为了评估澳大利亚昆士兰州一项黑素瘤病因家庭研究中此类信息的质量，作者将替代报告与通过邮寄自填问卷获得的黑素瘤标准风险因素的自我报告进行了比较。对于晒黑能力（多相相关系数（pc）=0.60）、肤色（pc = 0.57）、平均晒伤倾向（pc = 0.56）和21岁时的头发颜色（kappa系数 = 0.55）等问题，病例提供的替代报告与亲属的自我报告之间存在中度一致性，尽管处于极端风险因素类别的亲属至少有一半时间被替代者误分类。对于雀斑程度（pc = 0.45）、急性晒伤倾向（pc = 0.42）和疼痛性晒伤发作次数（pc = 0.23）等问题，一致性较低。亲属关于病例的替代报告质量与病例关于亲属的替代报告质量相似。报告有黑素瘤家族史的病例提供的替代信息比表明无家族史的病例更好，女性病例提供的替代报告比男性更好。病例对其父母和子女的报告能力比对其兄弟姐妹的报告能力更好。作者得出结论，当不可避免地使用黑素瘤风险因素的替代报告时，应根据潜在的高误分类率谨慎解释结果。特别是，替代报告似乎是对痣数量自我评估的相对较差的衡量标准，痣数量是已知最强的黑素瘤风险表型指标，可能会使有黑素瘤病史和无黑素瘤病史的家庭之间的比较产生偏差。
