Soh Sze-Ee, Barker Anna, Morello Renata, Dalton Megan, Brand Caroline
Department of Epidemiology and Preventative Medicine, Monash University, Melbourne, VIC, Australia.
Department of Physiotherapy, Alfred Health, Melbourne, VIC, Australia.
BMC Health Serv Res. 2016 Sep 20;16:497. doi: 10.1186/s12913-016-1744-4.
The Safety Attitudes Questionnaire (SAQ) is commonly used to assess staff perception of safety climate within their clinical environment. The psychometric properties of the SAQ have previously been explored with confirmatory factor analysis and found to have some issues with construct validity. This study aimed to extend the psychometric evaluations of the SAQ by using Rasch analysis.
Assessment of internal construct validity included overall fit to the Rasch model (unidimensionality), response formats, targeting, differential item functioning (DIF) and person-separation index (PSI).
A total of 420 nurses completed the SAQ (response rate 60 %). Data showed overall fit to a Rasch model of expected item functioning for interval scale measurement. The questionnaire demonstrated unidimensionality confirming the appropriateness of summing the items in each domain. Score reliabilities were appropriate (internal consistency PSI 0.6-0.8). However, participants were not using the response options on the SAQ in a consistent manner. All domains demonstrated suboptimal targeting and showed compromised score precision towards higher levels of safety climate (substantial ceiling effects).
There was general support for the reliability of the SAQ as a measure of safety climate although it may not be able to detect small but clinically important changes in safety climate within an organisation. Further refinement of the SAQ is warranted. This may involve changing the response options and including new items to improve the overall targeting of the scale.
This study was registered with the Australian New Zealand Clinical Trials Registry, number ACTRN12611000332921 (21 March 2011).
安全态度问卷（SAQ）常用于评估员工对其临床环境中安全氛围的认知。此前已通过验证性因素分析对SAQ的心理测量特性进行了探索，发现其在结构效度方面存在一些问题。本研究旨在通过使用拉施分析来扩展对SAQ的心理测量评估。
内部结构效度评估包括对拉施模型的整体拟合度（单维度性）、反应格式、目标定位、项目功能差异（DIF）和人员分离指数（PSI）。
共有420名护士完成了SAQ（回复率60%）。数据显示，对于区间量表测量，整体符合预期项目功能的拉施模型。该问卷显示出单维度性，证实了对每个领域的项目进行求和的适当性。得分信度合适（内部一致性PSI为0.6 - 0.8）。然而，参与者并未以一致的方式使用SAQ上的反应选项。所有领域的目标定位都不理想，并且在安全氛围较高水平时得分精度受到影响（存在明显的天花板效应）。
尽管SAQ作为安全氛围的一种测量方法的可靠性得到了普遍支持，但它可能无法检测到组织内安全氛围中微小但具有临床重要性的变化。有必要对SAQ进行进一步完善。这可能包括改变反应选项并纳入新项目，以改善量表的整体目标定位。
本研究已在澳大利亚新西兰临床试验注册中心注册，注册号为ACTRN12611000332921（2011年3月21日）。
