Self-help is increasingly accepted for the treatment of mental disorders, including psychosis, as both a provisional first step and a way to bridge the large treatment gap. Though mindfulness-based interventions do not belong to first line treatment strategies in psychosis and randomized controlled trials are lacking, encouraging preliminary findings speak for the usefulness of this approach. For the present study, we examined whether patients with psychosis benefit from mindfulness bibliotherapy.

A sample of 90 patients with psychosis (including a subsample with a verified diagnosis of schizophrenia) took part in the study via the Internet. Following baseline assessment, participants were randomized to either a mindfulness group or a Progressive Muscle Relaxation (PMR) control group and received the respective self-help manual including accompanying audio files. Symptom change was measured six weeks after the baseline assessment with self-rating scales including the Paranoia Checklist. The retention rate was 71%. The quality of the online dataset was confirmed by various strategies (e.g., psychosis lie scale; examination of response biases). The trial was registered at the ISRCTN registry (ISRCTN86762253).

No changes across time or between groups were noted for the Paranoia Checklist. Both conditions showed a decline in depressive and obsessive-compulsive symptoms at a medium effect size (per protocol and intention to treat analyses).

The study provided partial support for the effectiveness of self-help mindfulness and PMR for depression in psychosis. Whether mindfulness delivered by a licensed therapist might lead to improved treatment adherence and a superior outcome relative to PMR remains to be established. The results underscore that bibliotherapy is a worthwhile approach to narrow the large treatment gap seen in psychosis.