“…Seven studies included respondents from healthcare occupations (37,45,47,49,52,53,55). The remaining five studies were based on public employees (46,51), employees in an urban municipality (48), postal employees (31), and employees from mixed occupational groups (44). The time-lag between measurement time-points for studies using prospective research design varied between 3-84 months, although the majority of studies [10 studies (31, 36-39, 44, 45, 49, 50, 53] were based on 12-month time intervals.…”