Investigating the construct validity and reliability of the moral distress instrument: a systematic review

 Moral distress occurs when an individual feels dissatisfaction due to ethical conflicts and an inability to adhere to their moral principles, which can lead to depression and decreased job satisfaction. Measuring moral distress is crucial. Moreover, ensuring the validity and reliability of credible tools for assessing moral distress is essential. Therefore, the aim of the present study was to evaluate the psychometric properties of the Moral Distress Scale.

 In this scoping study, databases including PubMed, Scopus, Web of Science, Google Scholar, SID, and Magiran were systematically searched between 2001 and 2023 using keywords such as "Psychometric," "validity," "reliability," "moral," "distress," "scale," and their Persian equivalents ("روان سنجی," "روایی," "پایایی," "اخلاق," "پریشانی," "مقیاس"). Four researchers independently assessed the quality of the studies based on the Standards for Reporting Diagnostic Accuracy (STARD) checklist and the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2).

 Out of 2677 articles (321 Persian articles, 2356 English articles) retrieved, eight articles were ultimately evaluated. The quality of the studies was acceptable. The findings indicated that the number of factors extracted varied across studies, and both the Moral Distress Scale and the Revised Moral Distress Scale demonstrated appropriate validity and reliability. The internal consistency of the studies, as reported by Cronbach's alpha, ranged from 0.385 to 0.97. The lowest total variance of extracted factors was 19.38%, while the highest was 68.99%.

 There were evident limitations in the application of validation methods in the scales under review, and the Moral Distress Scale has not been widely used across different populations. Hence, the lack of application in various cultural contexts limits confidence in the scale's performance. The use of robust techniques for validation and further investigation of the validity and reliability of the Moral Distress Scale in future studies is recommended.