Institute of Mental Health, Buangkok Green Medical Park, Singapore 539747, Singapore.
Contemp Clin Trials. 2009 Sep;30(5):446-50. doi: 10.1016/j.cct.2009.04.006. Epub 2009 Apr 23.
Enrollment of an adequate number of subjects for a clinical trial is a perennial challenge and this might arguably be even more difficult and complex in trials involving patients with schizophrenia. In this paper, we used a modification of the Prospective Preference Approach (PPA) as a prelude to an actual randomized placebo-controlled trial of a cognitive-enhancing agent for patients with schizophrenia. This approach sought to test and enhance subjects' understanding of the key concepts of the trial, and administered the PPA at baseline and following a brief educational module. The motivations and concerns regarding potential participation in the proposed trial were also elicited by the PPA. Of one hundred ninety patients with schizophrenia recruited for this PPA study, only 12 (6.3%) were assessed to have understood all key trial-related concepts after the initial explanation and baseline PPA administration (prior to the educational module). Following the education module, however, there was significant increase in the number of patients who understood all key trial elements. Younger age and higher level of education were significant factors associated with better understanding of the proposed trial. The main reasons cited for wishing to participate in clinical trials were personal medical benefits and altruistic desire to help others. Concerns regarding the safety of the trial medication were expressed in over 80% of the subjects. PPA administration with educational module supplementation may provide a valuable addition to clinical trial procedures in patients with schizophrenia.
为临床试验招募足够数量的受试者是一个长期存在的挑战,而在涉及精神分裂症患者的试验中,这可能更加困难和复杂。在本文中,我们使用了前瞻性偏好方法(PPA)的修改版,作为对一种认知增强剂治疗精神分裂症患者的实际随机安慰剂对照试验的前奏。这种方法旨在测试和增强受试者对试验关键概念的理解,并在基线和简短的教育模块后进行 PPA 测试。PPA 还引出了受试者对潜在参与拟议试验的动机和担忧。在这项 PPA 研究中,共招募了 190 名精神分裂症患者,只有 12 名(6.3%)在初始解释和基线 PPA 管理(在教育模块之前)后被评估为理解了所有与试验相关的关键概念。然而,在教育模块之后,理解所有关键试验要素的患者数量显著增加。年龄较小和教育程度较高是与更好地理解拟议试验相关的重要因素。希望参加临床试验的主要原因是个人医疗获益和利他主义帮助他人的愿望。超过 80%的受试者对试验药物的安全性表示担忧。在精神分裂症患者中,使用 PPA 管理并辅以教育模块补充可能是临床试验程序的一个有价值的补充。