Ten studies were included in this review (n=905 patients; range 13 to 398): six RCTs; three non-controlled studies (one unpublished); and one programme evaluation study. Study quality (mean score 33.6, on a 9 to 45 point scale) and reporting (mean CONSORT score 12.5, on a 21-point scale) were adequate.
RCTs: Yoga was associated with moderate to large improvements in measures of anxiety (ES range 1.34 to 4.67; two RCTs), depression (ES range 1.31 to 7.44; two RCTs), stress (ES range 1.24 to 2.25; two RCTs), quality of sleep (ES 0.98; one RCT), mood (ES range 0.27 to 0.74; two RCTs), quality of life (ES range 0.28 to 1.51; three RCTs) and spiritual well-being (ES 0.39; one RCT). In one RCT yoga was associated with small improvements in measures of distress (ES 0.04), anxiety (ES 0.04) and depression (ES 0.17). Similarly small improvements were reported for fatigue (ES range 0.00 to 0.05; two RCTs).
Non-controlled trials: Overall, yoga was associated with moderate to large improvements in psychological outcome measures.