Table 1

 Baseline characteristics in the intervention (I) and control (C) groups, and mean length of sick leave

Baseline characteristics of randomised groupsNumber of sick-listedMean length of sick leaves (calendar days)Difference in mean length (calendar days)
ICp valueICI − C (95% CI)
Gender
    Males1921970.7492.097.4−5.4 (−27.9 to 17.1)
    Females303298100.1110.5−10.3 (−28.7 to 8.1)
Age group
    <41 years2462600.3788.893.2−4.4 (−22.6 to 13.7)
    >40 years249230105.1118.6−13.5 (−35.2 to 8.5)
Education
    ⩽12 years2682790.48107.3113.8−6.4 (−26.8 to 13.9)
    ⩾12 years22721684.894.3−9.5 (−28.9 to 9.9)
Diagnoses
    Low back pain1131230.46109.992.717.2 (−12.5 to 46.9)
    Rheumatic disorders and arthritis53460.46111.4179.6−68.3 (−123.3 to −13.3)
    Other musculoskeletal2502360.3793.392.70.5 (−18.1 to 19.1)
    Mental disorders79900.3580.7117.2−36.6 (−71.9 to −1.2)
Length of sick leave
    <12 weeks3283300.8935.535.6−0.1 (−3.1 to 2.9)
    ⩾12 weeks167165217.8244.6−26.8 (−51.0 to −2.7)
Total49549597.0105.3−8.3 (−22.5 to 6.0)