Time to first full RTW
Time to first full RTW was defined as the time to return to ordinary working hours (i.e. the hours they had worked before sick leave) for an uninterrupted period of 4 weeks. Time to first full RTW was assessed by a web-based questionnaire starting at baseline: ‘During the last 4 weeks, have you worked your ordinary hours for an uninterrupted period of at least 4 weeks’ (answer 1 = yes, 2 = no). During the 12-month follow-up, the following question was sent by text message every fourth week: “During the last 8 weeks, have you worked your ordinary working hours for an uninterrupted period of at least 4 weeks’ (1 = yes, 2 = no).