Table 1 Primary outcome measures

Self-efficacy

The General Self-Efficacy Scale

The scale assesses a general sense of perceived self-efficacy, aiming to predict coping ability and adaptation to stressful life events. The Scale has 10 questions with response choices on a 4-point scale: Not at all true/Hardly true/ Moderately true /Exactly true.

A higher mean self-efficacy score than the comparison group, by at least a third of a standard deviation, as measured by the General Self-Efficacy Scale [34], immediately after intervention completion and at 6 and 12 months post-baseline.

Depression

The Center for Epidemiologic Studies Depression Scale, Revised (CESD-R)

The Center for Epidemiologic Studies Depression Scale (CESD) is widely used in community samples. The 20 items in the CESD-R scale measure symptoms of depression in nine different groups as defined by the DSM-IV. Users are asked to rate the occurrence of symptoms ‘in the past week or so’ from 0 (Rarely or none of the time – less than one day) up to 4 (Nearly every day for two weeks)

A lower mean depression score than the comparison group, by at least a third of a standard deviation, as measured by The Center for Epidemiologic Studies Depression Scale, Revised (CESD-R) [35] at 6 and 12 months post-baseline.