BackgroundWhen enrolled in university or college, students receive varying degrees of training in managing practical situations in the workplace. However, after graduation, the young professionals meet their responsibilities at work. The experience of the transition between education and work may connote a feeling of professional uncertainty and lack of coping, both of which are important factors related to young professionals’ mental health. The gap between the two areas of knowledge is frequently described as ‘practice shock’. Very few studies of mental health among students and young professional workers have used longitudinal designs. In the present study, we conducted a longitudinal investigation of change and stability in the levels of psychological distress among healthcare professionals, teachers, and social workers from the end of their study programs until 3 years into their subsequent professional lives. We also assessed the extent to which psychological distress at the end of the study program, sociodemographic characteristics, coping with the professional role, the psychosocial workplace environment, and experience of overall quality of life can predict psychological distress 3 years into their professional lives.MethodsPsychological distress was measured using the General Health Questionnaire 12 (GHQ-12). A total of 773 students/young professionals participated at both the end of their study programs and 3 years into their professional lives. Group differences were examined by the chi-squared test, independent samples t-test, and one-way analysis of variance. McNemar’s test were applied to identify changes in the proportion of cases at the two time points. Linear and logistic regressions were employed to identify factors associated with GHQ-12 Likert scores and GHQ-12 case scores, respectively.ResultsPsychological distress was significantly reduced at 3 years for health professionals. Among the social workers and teachers, the change in psychological distress was not significant during the same period. Higher current quality of life contributed to lower psychological distress.ConclusionsOur findings support assumptions about higher levels of mental health problems as students, with mental health improving as health professionals and social workers move into professional work.