Establishing key components of yoga interventions for reducing depression and anxiety, and improving well-being: a Delphi method study

BACKGROUND: Previous research suggests benefits of yoga in reducing depression and anxiety. However, common concerns in reviews of the research include lack of detail, rationale and consistency of approach of interventions used. Issues related to heterogeneity include amount, types and delivery of yoga interventions. This study aims to document consensus-based recommendations for consistency of yoga interventions for reducing depression and anxiety. METHODS: The Delphi method was used to establish consensus from experienced yoga teachers. Thirty-three eligible teachers were invited to participate, from four different countries. Two rounds of an online survey were sent to participants. The first round sought initial views. The second round sought consensus on a summary of those views. Survey questions related to frequency and duration (dosage) of the yoga, approaches and techniques to be included or avoided, and training and experience for yoga teachers. RESULTS: Twenty-four teachers agreed to participate. Eighteen completed the second round (n = 18). General consensus (>75% of participants in agreement) was achieved on parameters of practice (dosage): an average of 30 to 40 minutes, to be done 5 times per week, over a period of 6 weeks. Numerous recommendations for yoga techniques to include or avoid were collected in the first round. The second round produced a consensus statement on those recommendations. Breath regulation and postures were considered very important or essential for people with depression; and relaxation, breath regulation and meditation being very important or essential for people with anxiety. Other recommended components also achieved consensus. There was also general consensus that it is very important or essential for teachers to have a minimum of 500 training hours over 2 years, at least 2 years teaching experience, training in developing personalised yoga practices, training in yoga for mental health, and professional supervision or mentoring. CONCLUSIONS: The Delphi process has achieved a consensus statement on the application of yoga for reducing anxiety and depression. This consensus provides a checklist for identification of commonalities and evaluation of past research. Future research can proceed to develop and evaluate consensus-based yoga intervention protocols for the reduction of anxiety and depression, and improvements in well-being. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12906-015-0614-7) contains supplementary material, which is available to authorized users.