Discipline of Public Health, University of Adelaide, Adelaide, SA 5005, Australia.
Clin Trials. 2013;10(3):483-94. doi: 10.1177/1740774513480568. Epub 2013 Apr 8.
We examined parents' consent preferences and understanding of an opt-in or opt-out invitation to participate in data linkage for post-marketing safety surveillance of childhood vaccines.
A single-blind parallel-group randomised controlled trial: 1129 families of babies born at a South Australian hospital in 2009 were sent information at 6 weeks post-partum, explaining data linkage of childhood immunisation and hospital records for vaccine safety surveillance, with 4 weeks to opt in or opt out by reply form, telephone, or email. At 10 weeks post-partum, 1026 (91%) parents were followed up by telephone interview.
In both the opt-in (n = 564) and opt-out arms (n = 565), four-fifths of the parents recalled receiving the information (81% vs. 83%, P = 0.35), three-fifths reported reading it (63% vs. 67%, P = 0.11), but only two-fifths correctly identified the health records to be linked (43% vs. 39%, P = 0.21). Parents who actively consented (opted in) were more likely than those who passively consented (did not opt out) to recall the information (100% vs. 83%, P < 0.001), report reading it (94% vs. 67%, P < 0.001), and correctly identify the data sources (60% vs. 39%, P < 0.001). Most parents supported data linkage for vaccine safety surveillance (94%) and trusted its privacy protections (84%). Most parents wished to have minimal or no direct involvement, preferring either opt-out consent (40%) or no consent (30%). A quarter (24%) of parents indicated opt-in consent should be sought; of these, 8% requested consent prior to every use, 5% preferred to give broad consent just once and 11% preferred periodic renewal. Three-fifths of the parents gave higher priority to rapid vaccine safety surveillance (61%) rather than first seeking parental consent (21%), and one in seven was undecided (15%). Although 91% of parents reported that their babies were fully immunised (76%) or under-immunised (15%), and trusted vaccines as safe (90%), three-fifths (62%) were very or somewhat concerned about serious reactions.
The context of data linkage is limited to vaccine safety surveillance. Only recall and understanding retained at 1 month post enrolment were measured.
This trial demonstrates that informed consent for a population-based surveillance programme cannot realistically be achieved using mail-based opt-in and opt-out approaches. While recall and understanding of the study's purpose were better among parents who actively consented (opted in) compared with parents who passively consented (did not opt out), participation was substantially lower (21% vs. 96% respectively). Most parents appeared to have a poor understanding of data linkage for vaccine safety surveillance; nonetheless, they supported data linkage. They preferred a system utilising opt-out consent or no consent to one using opt-in consent.
我们调查了父母对参与儿童疫苗上市后安全性监测的选择加入或选择退出邀请的同意偏好和理解。
一项单盲平行组随机对照试验：2009 年在南澳大利亚一家医院出生的 1129 个家庭在产后 6 周时收到了信息，说明儿童免疫接种和医院记录的数据链接用于疫苗安全性监测，有 4 周的时间通过回复表、电话或电子邮件选择加入或退出。在产后 10 周时，通过电话采访对 1026 名（91%）父母进行了随访。
在选择加入（n=564）和选择退出（n=565）两组中，五分之四的父母回忆收到了信息（81%对 83%，P=0.35），五分之三的父母报告阅读了信息（63%对 67%，P=0.11），但只有五分之二的父母正确识别了要链接的健康记录（43%对 39%，P=0.21）。积极同意（选择加入）的父母比被动同意（未选择退出）的父母更有可能回忆起信息（100%对 83%，P<0.001），报告阅读了信息（94%对 67%，P<0.001），并正确识别了数据源（60%对 39%，P<0.001）。大多数父母支持数据链接用于疫苗安全性监测（94%）并信任其隐私保护（84%）。大多数父母希望最小化或不直接参与，更喜欢选择退出同意（40%）或不同意（30%）。四分之一（24%）的父母表示应该寻求选择加入同意；其中，8%的父母要求在每次使用前获得同意，5%的父母更喜欢一次性给予广泛的同意，11%的父母更喜欢定期更新。五分之三的父母更重视快速疫苗安全性监测（61%）而不是首先寻求父母同意（21%），七分之一的父母犹豫不决（15%）。尽管 91%的父母报告说他们的孩子已经完全接种疫苗（76%）或接种不足（15%），并信任疫苗的安全性（90%），但五分之三（62%）的父母非常或有些担心严重反应。
数据链接的背景仅限于疫苗安全性监测。仅测量了在入组后 1 个月时保留的回忆和理解。
这项试验表明，对于基于人群的监测计划，通过基于邮件的选择加入和选择退出方法不可能实现知情同意。虽然与被动同意（未选择退出）的父母相比，积极同意（选择加入）的父母对研究目的的回忆和理解更好，但参与率明显较低（分别为 21%和 96%）。大多数父母似乎对疫苗安全性监测的数据链接理解很差；尽管如此，他们还是支持数据链接。他们更喜欢使用选择退出同意或不同意的系统，而不是使用选择加入同意的系统。
