Department of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA.
Patient. 2011;4(4):267-75. doi: 10.2165/11589190-000000000-00000.
Schizophrenia is a severe mental illness associated with hallucinations, delusions, apathy, poor social functioning, and impaired cognition. Researchers and funders have been hesitant to focus efforts on treatment preferences of patients with schizophrenia because of the perceived cognitive burden that research methods, such as conjoint analysis, place on them.
The objective of this study was to test if patients diagnosed with schizophrenia were able to complete a choice-based conjoint analysis (often referred to as discrete-choice experiments) and to test if meaningful trade-offs were being made.
German outpatients diagnosed with schizophrenia were eligible to participate in this study if they were aged 18-65 years, had received treatment for at least 1 year and were not experiencing acute symptoms. Conjoint analysis tasks were based on six attributes, each with two levels, which were identified via a literature review and focus groups. A psychologist in a professional interview facility presented each respondent with the eight tasks with little explanation. All interviews were recorded, transcribed, and analyzed to verify that respondents understood the tasks. Preferences were assessed using logistic regression, with a correction for clustering.
We found evidence that the 21 patients diagnosed with schizophrenia participating in the study could complete conjoint analysis tasks in a meaningful way. Patients not only related to the scenarios presented in conjoint tasks, but explicitly stated that they used their own preferences to judge which scenarios were better. Statistical analysis confirmed all hypotheses about the attributes (i.e. all attributes had the expected sign). Having a supportive physician, not feeling slowed, and improvements in stressful situations (p < 0.01) were the most important attributes.
We found that patients diagnosed with schizophrenia can complete conjoint analysis tasks, that they base their decisions on their own preferences, and that patients make trade-offs between attributes.
精神分裂症是一种严重的精神疾病，其症状包括幻觉、妄想、冷漠、社交功能障碍和认知受损。由于认为研究方法（如联合分析）会给患者带来认知负担，研究人员和资助者一直不愿意将精力集中在精神分裂症患者的治疗偏好上。
本研究旨在检验精神分裂症患者是否能够完成基于选择的联合分析（通常称为离散选择实验），并检验他们是否做出了有意义的权衡。
符合以下条件的德国门诊精神分裂症患者有资格参加本研究：年龄在 18-65 岁之间；接受治疗至少 1 年；无急性症状。联合分析任务基于通过文献回顾和焦点小组确定的六个属性，每个属性有两个水平。心理学家在专业访谈设施中向每位受访者呈现八项任务，几乎没有解释。所有访谈都进行了录音、转录和分析，以验证受访者理解任务。使用逻辑回归评估偏好，并对聚类进行校正。
我们发现，参加研究的 21 名被诊断为精神分裂症的患者能够以有意义的方式完成联合分析任务。患者不仅与联合任务中呈现的情景相关，而且明确表示他们使用自己的偏好来判断哪些情景更好。统计分析证实了关于属性的所有假设（即所有属性都具有预期的符号）。有一个支持性的医生、感觉不迟钝和改善紧张情况（p<0.01）是最重要的属性。
我们发现，被诊断为精神分裂症的患者可以完成联合分析任务，他们根据自己的偏好做出决策，并且在属性之间做出权衡。
