Feine J S, Awad M A, Lund J P
McGill University Faculty of Dentistry, Jewish General Hospital, Lady Davis Institute for Medical Research, Montreal, Quebec, Canada.
Community Dent Oral Epidemiol. 1998 Feb;26(1):70-4. doi: 10.1111/j.1600-0528.1998.tb01927.x.
Research on several health problems shows that patients and health care providers do not use the same criteria to evaluate the effectiveness of treatment and often disagree on the severity of symptoms. When the disease is chronic and the main aim of treatment is to improve quality of life, we argue that variables rated as important by patients should be used as outcomes in clinical trials, and that in most cases these need to be measured from subjects' self-reports. In many non-pharmacological randomized clinical trials, the subjects cannot be blinded to treatment. Furthermore, many of them will probably have a preference for a particular treatment option. It has been proposed that emotional responses following assignment of treatments, which may or may not be preferred, will strongly influence the outcome, especially when it is based on self-reports of treatment satisfaction. Because of this concern, some investigators have suggested alternative study designs that incorporate preference. Brewin & Bradley (Br Med J 1989; 299 [6694]:313-5) have proposed allocating subjects to treatment methods according to their preferences, and randomizing those individuals with no preference. To determine the influence of preference on treatment outcome, they recommend comparing results from the preference group with those of the randomized group. However, we have found that there are clear differences in level of education and in the pre-treatment state between individuals with preferences and those with no strong preferences. Therefore, we believe that the design proposed by Wennberg et al. (Ann N Y Acad Sci 1993;703:52-62) is more appropriate. In it, subjects are randomly allocated to a preference trial (subjects choose their treatment) or to a randomized trial (random allocation to treatment). Between-trial comparisons can then be used to determine the influence of preference on outcome. This will lead to better evaluation of treatment efficacy and allow better estimates of the true effectiveness to be made.
多项健康问题研究表明，患者和医疗服务提供者在评估治疗效果时所采用的标准并不相同，而且在症状严重程度方面常常存在分歧。当疾病为慢性且治疗的主要目标是提高生活质量时，我们认为，患者认为重要的变量应作为临床试验的结果，并且在大多数情况下，这些变量需要通过受试者的自我报告来衡量。在许多非药物随机临床试验中，受试者无法对治疗保持盲态。此外，他们中的许多人可能会对特定的治疗方案有偏好。有人提出，接受治疗（无论是否是偏好的治疗）后的情绪反应会强烈影响结果，尤其是当结果基于治疗满意度的自我报告时。出于这种担忧，一些研究人员提出了纳入偏好因素的替代研究设计。布鲁因和布拉德利（《英国医学杂志》1989年；299[6694]：313 - 5）建议根据受试者的偏好将其分配至治疗方法，对无偏好的个体进行随机分组。为了确定偏好对治疗结果的影响，他们建议将偏好组的结果与随机分组的结果进行比较。然而，我们发现，有偏好的个体与无强烈偏好的个体在教育水平和治疗前状态方面存在明显差异。因此，我们认为温伯格等人（《纽约科学院年报》1993年；703：52 - 62）提出的设计更为合适。在该设计中，受试者被随机分配至偏好试验（受试者选择自己的治疗方法）或随机试验（随机分配治疗方法）。然后可以通过试验间比较来确定偏好对结果的影响。这将有助于更好地评估治疗效果，并能更准确地估计真实疗效。
