Objective To develop and evaluate a new patient-reported outcome measure (PROM) to assess people’s knowledge and beliefs about low back pain. Methods This study followed the COnsensus-based Standards for the selection of health Measurement INstruments guidelines. An 18-item preliminary version of the Back pain Knowledge and beliefs Survey (BacKS) was generated based on evidence-based key messages and current clinical guidelines for low back pain. Four items were added following input from three consumers and seven experts. Focus groups (n=9) confirmed content validity. The 22-item version was completed by 258 Australian-based adults (>18 years) with self-reported low back pain. A follow-up survey was sent 1 week later. The following measurement properties were evaluated to produce, and then assess the final version of BacKS: structural validity (exploratory factor analysis); internal consistency (Cronbach’s alpha); test–retest reliability (intraclass correlation coefficient); measurement error (Smallest Detectable Change); construct validity (hypothesis tested: moderate positive Pearson correlation between BacKS and Back Beliefs Questionnaire); plus, interpretability and feasibility. Results The final BacKS comprised 20 items with a 2-factor structure (biomedical factor: 9 items, score ranging from 9 to 45, and self-care factor: 11 items, score ranging from 11 to 55). Internal consistency and reliability were adequate (>0.70) for each factor. Smallest detectable change was 4.4 (biomedical factor) and 7.0 (self-care factor). Our construct validity hypothesis was confirmed (Pearson correlation=0.53). No floor or ceiling effects were detected. Conclusion The BacKS is a valid, reliable and feasible PROM to measure knowledge and beliefs about low back pain in clinical practice and research settings. Data are available on reasonable request.

中文翻译：

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背痛知识和信念调查 (BacKS)：测量属性的开发和评估


目的 开发和评估一种新的患者报告结果测量（PROM），以评估人们对腰痛的知识和信念。方法 本研究遵循基于共识的标准来选择健康测量仪器指南。背痛知识和信念调查 (BacKS) 的 18 项初步版本是根据基于证据的关键信息和当前腰痛临床指南生成的。根据三位消费者和七位专家的意见，添加了四项。焦点小组（n=9）确认了内容的有效性。该版本包含 22 项内容，由 258 名自述患有腰痛的澳大利亚成年人（>18 岁）完成。 1周后发送了一份后续调查。评估以下测量属性以产生并评估 BacKS 的最终版本：结构有效性（探索性因素分析）；内部一致性（Cronbach's alpha）；重测信度（组内相关系数）；测量误差（最小可检测变化）；构造效度（假设检验：BacKS 和后置信念问卷之间的中度正皮尔逊相关）；另外，可解释性和可行性。结果最终的BacKS由20个项目组成，具有2因素结构（生物医学因素：9个项目，得分范围为9至45，自我保健因素：11个项目，得分范围为11至55）。每个因素的内部一致性和可靠性都足够（>0.70）。可检测到的最小变化为 4.4（生物医学因素）和 7.0（自我护理因素）。我们的构建有效性假设得到了证实（皮尔逊相关=0.53）。未检测到地板或天花板效应。 结论 BacKS 是一种有效、可靠且可行的 PROM，可用于测量临床实践和研究环境中有关腰痛的知识和信念。可根据合理要求提供数据。