Stress measures Occupational stress was assessed using the validated Italian versions40 of two standardised questionnaires: DCS questionnaire, derived from the longer Job Content Questionnaire,16 and the ERI questionnaire.17 DCS is a 17-item self-report questionnaire that provides scores on three scales: Psychological Job Demand, (Demand, 5 items mapping quantitative aspects of work, such as time required to perform tasks and conflict among different demands), Job Control/Decision Latitude (Control, 6 items mapping the use and development of skills and autonomy in making decisions about the work process) and Workplace Social Support (Support, 6 items mapping relationships between coworkers and superiors). Participants are asked to rate each item on a four-point frequency (Demand and Control) or agreement (Support) scale. In this study reliabilities (Cronbach’s α) of the scales were 0.71, 0.65 and 0.84, respectively. Along with scale sum scores, a further index, ‘perceived job strain’ (DCS job strain) was computed by dividing the mean item score of Demand by the mean item score of the Control scale. A ratio of 1 indicates a balance between Demand and Control; values >1 indicate excessive perceived job strain.41 ERI is a 23-item self-report questionnaire that assesses three dimensions: Effort (6 items mapping the demanding aspects of the work environment), Reward (11 items mapping the occupational rewards that the worker expects to receive) and Overcommitment (6 items mapping the intrinsic personal factors regarding occupational motivation and participation that enhance the effects of stress). Participants are asked to rate each item on a five-point intensity scale. In this study, reliabilities of the scales were 0.82, 0.89 and 0.79, respectively. Along with scale sum scores, the weighted ratio between effort and reward (E/R ratio) was computed to quantify the degree of mismatch between effort and reward. Values >1 reflect an imbalance that can induce stress.