Assessment of Knowledge, Attitudes, and Behaviors Toward Others' Mental Disorders to Improve Mental Health First Aid: Cross-Sectional Study in a French Workplace.

BACKGROUND: Mental distress represents a major public health challenge worldwide, affecting work ability, productivity, and social functioning. Public-sector employees face high psychosocial demands, but data on their mental health literacy and supportive behaviors remain scarce. Mental Health First Aid (MHFA) aims to improve knowledge, attitudes, and behaviors (KAB) toward psychological distress among nonspecialists, but evidence among civil servants and on skill retention over time is limited. OBJECTIVE: This study aimed (1) to determine KAB related to psychological distress among French civil servants, (2) to examine associations between KAB scores and MHFA training exposure, and (3) to explore gradients according to time since training as an indirect indicator of potential retention of MHFA-related competencies. METHODS: A nationwide cross-sectional survey was conducted in November 2025 among French civil servants. Participants completed an online questionnaire adapted from a published instrument. The 3 dimension scores were normalized to a 0-40 scale, yielding a total KAB score of 0-120, categorized as inadequate (0-70), marginal (71-88), or adequate (89-120). Multivariable linear regression models identified factors associated with KAB outcomes, adjusting for sociodemographic and professional variables. RESULTS: Among 338,560 eligible civil servants invited by email, 6526 (1.93%) initiated the questionnaire, and 4679 (1.38% of those invited) fully completed it and were included in the analysis. Participants were predominantly women (3022/4679, 64.59%), aged 40-69 years (4317/4679, 92.26%), and belonged to professional category A (2207/4679, 47.17%). The mean total KAB score was 82.88 (SD 19.14; 95% CI 82.33-83.43), corresponding to a marginal level. Mean subscores were 31.31 (SD 5.26; 95% CI 31.16-31.46) for knowledge, 29.72 (SD 11.52; 95% CI 29.39-30.05) for attitudes, and 21.86 (SD 7.96; 95% CI 21.63-22.09) for behaviors. MHFA-trained participants (545/4679, 11.65%) obtained significantly higher total KAB scores than untrained participants (mean 95.56, SD 14.17; 95% CI 94.37-96.75 vs mean 81.21, SD 19.09; 95% CI 80.63-81.79; P<.001), with higher scores for knowledge (mean 33.31, SD 5.26 vs mean 31.04, SD 5.35), attitudes (mean 34.35, SD 8.81 vs mean 29.10, SD 11.70), and behaviors (mean 27.87, SD 6.13 vs mean 21.06, SD 7.84; all P<.001). Among MHFA-trained participants, scores decreased over time (<6 months, 6-12 months, >12 months; P<.001), but remained higher than in untrained individuals even beyond 12 months after training. In adjusted models, MHFA training was strongly associated with higher KAB scores (β=14.63 for <6 months; β=13.61 for 6-12 months; β=10.33 for >12 months; all P<.001). Lower scores were observed in professional categories B and C and among men. CONCLUSIONS: Mental health literacy and supportive behaviors among French civil servants remain heterogeneous and, on average, marginal. MHFA training is associated with substantially higher KAB scores, even beyond 12 months, supporting its role as a public health literacy intervention in occupational settings. Declining scores over time supports reinforcement strategies to sustain competencies.