Increasing social support for individuals with serious mental illness: evaluating the compeer model of intentional friendship.

We conducted a quasi-experimental study of Compeer, which matches community volunteers and people with SMI to increase social support. Seventy-five adults with SMI received community psychiatric treatments-usual (TAU) while 79 adults received Compeer services plus TAU. Compeer clients reported significant improvements in social support and a trend towards improved subjective well-being. After 6 months, social support increased >1 SD for 13%, increasing to 23% at 12 months, supporting qualitative research suggesting the "active ingredient" in intentional friendships often takes more than 1 year to develop. This subgroup of responders showed significant gains in subjective well-being and reductions in psychiatric symptoms.