Norell S E, Boethius G, Persson I
Department of Pulmonary Medicine, Ostersund Hospital, Sweden.
Int J Epidemiol. 1998 Dec;27(6):1033-7. doi: 10.1093/ije/27.6.1033.
If women tend to forget and underreport their past oral contraceptive (OC) use, but the recall among cases is enhanced by the presence of disease, recall bias may explain some reported health effects of OC use.
Two different sources of information on lifetime OC use were compared for 427 (84%) of a community-based sample of 511 women aged 20-34: (i) structured interviews, using a life event calendar and picture display as memory aids, and (ii) a register of all prescriptions dispensed by pharmacies in the county since 1970.
Interview data and pharmacy records showed high levels of agreement for any OC use, current use, time since first and last use, total duration of use, and for duration of use in different 'time windows'. But there was a tendency to under-report specific kinds of OC used in the past.
Underreporting of OC use among non-cases would usually introduce little or no bias (as compared to pharmacy records) for this kind of interview and women. However, it may be preferable to use interviews for current OC use, and pharmacy records for specific kinds of OC used in the past.
如果女性往往会忘记并少报她们过去使用口服避孕药（OC）的情况，而病例组中的回忆因疾病的存在而增强，那么回忆偏倚可能会解释一些所报道的使用OC的健康影响。
对511名年龄在20 - 34岁的社区样本中的427名女性（84%），比较了关于终生使用OC的两种不同信息来源：（i）使用生活事件日历和图片展示作为记忆辅助工具的结构化访谈，以及（ii）自1970年以来该县药房所有配药的登记记录。
访谈数据和药房记录在任何OC使用、当前使用、首次和末次使用时间、总使用时长以及不同“时间窗口”内的使用时长方面显示出高度一致性。但存在少报过去使用的特定种类OC的倾向。
对于这类访谈和女性而言，非病例组中对OC使用情况的少报通常不会引入偏差（与药房记录相比）或只会引入极少偏差。然而，对于当前OC使用情况，使用访谈可能更可取，而对于过去使用的特定种类OC，则使用药房记录可能更可取。
