Linguistic and psychometric validation of a German version of the measure of moral distress for healthcare professionals (MMD-HP GER): results of a study with intensive care nurses

BACKGROUND: Moral distress is an increasingly studied phenomenon in nursing science and ethics. It refers to the psychological discomfort experienced when an individual is prevented from acting on a course of action that they recognize as ethically correct. Nurses who work in intensive care are at high risk of experiencing moral distress. Various instruments to assess moral distress, most recently Epstein et al.'s measure of moral distress for health care professionals (MMD-HP), have been developed. At present, there is no validated German language version of the instrument for assessing moral distress in Germany. Therefore, this study aimed, at (1) translating and linguistically validating the instrument, as well as (2) psychometrically validating it among intensive care nurses in Germany. METHODS: According to the ISPOR (International Society for Pharmacoeconomics and Outcomes Research) guidelines, the MMD‑HP was translated, linguistically validated, and psychometrically tested. The German version of the moral distress thermometer (MDT) and the German Nursing Workload Scale (NWS) were used to measure the construct validity of the translated instrument. Institutional ethics review boards of two universities approved the study protocols. RESULTS: A total of 187 questionnaires of intensive care nurses remained for analysis after listwise deletion. The mean sum‑score was 106.9 (± 62) (minimum = 3, maximum = 325; range = 0-400). Criterion validity was supported by a high positive correlation between the German version of the MMD‑HP and the validated German-language moral distress thermometer (ρ = 0.598, p = 0.001, n = 168). Factor analyses revealed a four‑factor solution with correlating factors for the German version. The instrument showed high reliability (ωH = 0.91, 95 % CI = 0.88-0.93). CONCLUSIONS: Our findings demonstrate that the German adaptation of the MMD-HP shows potential for measuring moral distress among intensive care nurses in Germany. In addition, its psychometric properties preliminarily support its reliability and validity in this cultural context. Further independent validation studies are needed to provide support for the proposed four-factor model.