German translation and psychometric evaluation of the Mental Health Literacy Scale (MHLS-GER) in a general population sample and in patients with acute myocardial infarction

Background: The Mental Health Literacy Scale (MHLS) is a scale-based measure with 35 items that assesses various aspects of mental health literacy. The original English version was developed in Australia and has been translated into several languages. The present study aimed to translate and culturally adapt the questionnaire for its use in Germany and to determine the psychometric properties of the German version of the MHLS (MHLSGER) in two different samples. Methods: After translation and cultural adaptation, the MHLS-GER was administered via an online survey in a general population sample and via a postal survey in patients with acute myocardial infarction (AMI). Exploratory factor analysis and confirmatory factor analysis were conducted to determine the dimensionality. Furthermore, internal consistency, known-groups-validity and measurement invariance were evaluated. Results: Data of 517 participants of the general population sample and 786 participants of the AMI sample were analyzed. In both samples a four-factor structure yielded good model fit indices. The four subscales of the MHLSGER including 31 items comprise the topics 'knowledge' (11 items), 'information seeking' (4 items), 'stigmatization' (9 items) and 'social distance' (7 items). All four subscales showed good internal consistency (Cronbach's alpha: 0.80 to 0.90, average inter-item correlation: 0.30-0.59) and were mostly invariant across the two samples. Participants with previous experience with mental disorders (personal or professional context) showed higher scores on the four subscales. Conclusion: In contrast to the unidimensional structure of the original version, the MHLS-GER comprises four subscales. All subscales showed acceptable to good psychometric properties and can now be used to assess mental health literacy. Further validation studies to evaluate test-retest-reliability and responsiveness are required.