Beck N C, Hall D
Obstet Gynecol. 1978 Sep;52(3):371-9.
A review and critique of the literature relating to the effectiveness of psychoprophylaxis (natural childbirth) is made. Based on this review, it is concluded that a variety of methodologic errors have confounded the measurement of treatment effects. An outline of these issues is presented, and it is pointed out that an elucidation of the relationship between treatment and outcome cannot occur until researchers become aware of certain factors that are essential to the validity of their experiments. These factors include the following: 1) the use of a random assignment of subjects to treatment and control groups; 2) the inclusion of a group of controls that receive an attention-placebo treatment; 3) the utilization of obstetricians who are unaware of the type of preparation their patients have received; 4) a careful specification of the details of each treatment procedure; and 5) the utilization of psychologic tests that are appropriate for the purpose of measuring pain and anxiety reduction.
对有关心理预防（自然分娩）有效性的文献进行了综述和批判。基于此综述，得出的结论是，各种方法学错误混淆了治疗效果的测量。本文列出了这些问题的概要，并指出，在研究人员意识到对其实验有效性至关重要的某些因素之前，无法阐明治疗与结果之间的关系。这些因素包括：1）将受试者随机分配到治疗组和对照组；2）纳入一组接受注意力安慰剂治疗的对照组；3）利用不知道其患者接受何种准备类型的产科医生；4）仔细说明每个治疗程序的细节；5）利用适合测量疼痛和焦虑减轻目的的心理测试。
