Sackett David L
Kilgore S. Trout Research & Education Center, Irish Lake, Ontario, Canada.
Pol Arch Med Wewn. 2011 Jul-Aug;121(7-8):259-63.
Most clinical trials assessing the role of a specific intervention attempt to answer an explanatory question: under ideal circumstances of risk and responsiveness, can the expert care of individual with a particular condition reduce their risks of a relevant but restricted set of outcomes? Such explanatory trials (also called efficacy trials) are of direct relevance to expert clinicians and their highly compliant patients. Another question, potentially of broader clinical or health care policy relevance is: Does this treatment improve patient-important outcomes when applied by typical clinicians to typical patients? Answering this latter question is the goal of pragmatic trial, also labeled by some as "management" or "effectiveness" trial. The methodological and organizational differences between explanatory and pragmatic trials include, among others, patients eligibility (restricted to highly responsive and compliant patients in explanatory trials vs. everyone with condition of interest in pragmatic trials), experimental and comparator intervention (blinded and inflexible with strict instructions vs. flexible with cross-over permitted and no blinding), types of practitioners (only those with documented high expertise vs. all who usually provide given mode of care), and outcome measurement (often limited to biologic effects vs. broad overall health effects sometimes based on administrative data bases on mortality and utilization). Those aspects of study design and conduct and their role in determining a place of an intervention in clinical practice are reviewed in this paper.
在理想的风险和反应性条件下，针对特定疾病个体的专家护理能否降低他们发生一组相关但有限的不良后果的风险？这类解释性试验（也称为疗效试验）与专家临床医生及其高度依从的患者直接相关。另一个可能具有更广泛临床或医疗保健政策相关性的问题是：当典型临床医生将这种治疗应用于典型患者时，它是否能改善对患者重要的结局？回答后一个问题是实用试验的目标，也有一些人将其称为“管理”或“有效性”试验。解释性试验和实用试验在方法和组织上的差异包括患者入选标准（解释性试验限于高度反应性和依从性的患者，而实用试验为所有患有相关疾病的患者）、试验性和对照性干预措施（解释性试验中采用盲法且严格按照固定说明，而实用试验灵活，允许交叉且不设盲）、从业者类型（解释性试验仅为有记录的高专业水平者，而实用试验为所有通常提供特定护理模式的人员）以及结局测量（解释性试验通常限于生物学效应，而实用试验有时基于死亡率和利用率的行政数据库测量广泛的总体健康效应）。本文将对研究设计与实施的这些方面及其在确定干预措施在临床实践中的地位所起的作用进行综述。
