Managing job strain: A randomized controlled trial of an intervention conducted by mail and telephone

Employees of San Mateo County were invited to participate in a 1-year stress management program. The 81 volunteers were randomly assigned to one of three groups. All three groups completed a Job Content Survey at baseline and 1 year and a Health Risk Appraisal (HRA) at baseline, 6 months and, 1 year. The 'materials plus phone' group also received materials by mail, including a workbook with modules on reducing stress at home and at work, a book, an audio tape, a stress card with results of the HRA screening, and telephone calls from a health educator approximately every 6 weeks. The 'materials only' group received all the materials but no telephone calls. A control group received only the assessment during the study, but after the study, they received all the materials. Both intervention groups showed improvements in stress-related measures that were statistically greater than the control group, but no improvements in general health measures were found. The 'materials plus phone' group showed greater improvement than the 'materials only' group.