School of Social and Community Medicine, University of Bristol, Bristol, UK; NIHR Collaboration for Leadership in Applied Health Research and Care West, Hosted by University Hospitals Bristol NHS Foundation Trust, Bristol, UK.
School of Social and Community Medicine, University of Bristol, Bristol, UK.
J Clin Epidemiol. 2018 Apr;96:35-46. doi: 10.1016/j.jclinepi.2017.12.019. Epub 2017 Dec 27.
Randomized controlled trials (RCTs) deliver robust internally valid evidence but generalizability is often neglected. Design features built into the Prostate testing for cancer and Treatment (ProtecT) RCT of treatments for localized prostate cancer (PCa) provided insights into its generalizability.
Population-based cluster randomization created a prospective study of prostate-specific antigen (PSA) testing and a comprehensive-cohort study including groups choosing treatment or excluded from the RCT, as well as those randomized. Baseline information assessed selection and response during RCT conduct.
The prospective study (82,430 PSA-tested men) represented healthy men likely to respond to a screening invitation. The extended comprehensive cohort comprised 1,643 randomized, 997 choosing treatment, and 557 excluded with advanced cancer/comorbidities. Men choosing treatment were very similar to randomized men except for having more professional/managerial occupations. Excluded men were similar to the randomized socio-demographically but different clinically, representing less healthy men with more advanced PCa.
The design features of the ProtecT RCT provided data to assess the representativeness of the prospective cohort and generalizability of the findings of the RCT. Greater attention to collecting data at the design stage of pragmatic trials would better support later judgments by clinicians/policy-makers about the generalizability of RCT findings in clinical practice.
随机对照试验（RCT）提供了强有力的内部有效性证据，但通常忽略了其可推广性。前列腺癌检测和治疗（ProtecT）RCT 中针对局限性前列腺癌（PCa）治疗的设计特点为其可推广性提供了一些见解。
基于人群的聚类随机化创建了一项前列腺特异性抗原（PSA）检测的前瞻性研究和一项综合队列研究，包括选择治疗或排除在 RCT 之外的群体，以及那些随机分组的群体。在 RCT 进行期间，基线信息评估了选择和反应。
前瞻性研究（82430 名接受 PSA 检测的男性）代表了可能对筛查邀请做出反应的健康男性。扩展的综合队列包括 1643 名随机分组、997 名选择治疗和 557 名因晚期癌症/合并症而排除在外的患者。选择治疗的男性与随机分组的男性非常相似，除了他们有更多的专业/管理职业。排除在外的男性在社会人口统计学方面与随机分组的男性相似，但在临床方面有所不同，他们代表了不太健康的男性，患有更晚期的 PCa。
ProtecT RCT 的设计特点提供了数据来评估前瞻性队列的代表性和 RCT 发现的可推广性。在实用试验的设计阶段更加关注收集数据，将更好地支持临床医生/决策者以后对 RCT 发现在临床实践中的可推广性的判断。
