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.

A number of recommendations have been made about HOW OFTEN and FOR HOW LONG a person would need to do the yoga, in order to gain benefit.
The yoga practice would be individually tailored in consultation with an experienced teacher, done regularly at home, and in conjunction with other treatments.
These are general recommendations only, and are summarised below. For each question 4 to 6, please indicate if you agree or disagree. There are many components of yoga practice, that include various approaches and techniques. It is generally agreed that yoga is most beneficial when these different components or techniques are used with an integrated approach. That is, in combination or conjunction with each other. This integrated approach includes particular recommendations for each of the components and techniques being used.
It is recommended that various approaches and techniques are always done in accordance with the level of ability of each individual, and may also be beneficial in conjunction with other forms of treatment.
Questions 7 to 14 include the components of yoga practice that were recommended as beneficial for reducing depression, and improving wellbeing.
Whilst these tools or techniques are often used in combination or conjunction with other techniques, questions 7 to 10 focus in the basic approach for each of the main components themselves, which does not exclude the possibility of using different or additional components in combination. n m l k j n m l k j n m l k j n m l k j    n m l k j n m l k j n m l k j n m l k j 11. All these components, and combinations of them, are considered to be beneficial for reducing depression.
The first questionnaire also asked participants to rate the IMPORTANCE of each component.
Using a rating scale from 1=not recommended to 5=essential, these components of yoga practice for reducing depression were rated by participants as either "very important" or "essential" as follows: 1st: Regulation of breathing (pranayama) (95% of participants, with an "importance" rating of 4.4) 2nd: Yoga postures (asana) (76% of participants, "importance" rating of 4.1) 3rd and 4th: Relaxation and meditation were rated similarly (55% and 57% of participants, with an "importance" rating of 3.8 and 3.6 respectively) Do you agree with this overall rating of the relative importance of these components of yoga for reducing DEPRESSION?
12. There was general consensus that this order of relative importance would be the same for using yoga to increase positive emotion and wellbeing in people with depression.
Do you agree? The previous section was for the reduction of depression and improving wellbeing. The following section is for the reduction of anxiety and improving wellbeing. There are many similarities in approach, and some important differences.

REDUCING DEPRESSION AND IMPROVING WELLBEING
Again, it is emphasised that yoga is most beneficial when the different components or techniques are used with an integrated approach. That is, in combination or conjunction with each other. This integrated approach also includes particular recommendations for each of the components and techniques being used.
It is recommended that various approaches and techniques are always done in accordance with the level of ability of each individual, and may also be beneficial in conjunction with other forms of treatment.
Questions 16 to 23 include the components of yoga practice that were recommended as beneficial for reducing ANXIETY, and improving wellbeing.
Whilst these tools or techniques are often used in combination or conjunction with other techniques, questions 16 to 19 focus in the basic approach for each of the main components themselves, which does not exclude the possibility of using different or additional components in combination.
16. The following approaches to YOGA POSTURES (asana) have been recommended as important components of yoga practice for reducing anxiety. This question seeks to clarify the relative importance of these factors. 19. The following approaches to MEDITATION have been recommended as an important component of yoga practice for reducing anxiety. This question seeks to clarify the relative importance of these factors.
For REDUCING ANXIETY, how important is it that MEDITATION is done with a focus on:

REDUCING ANXIETY AND IMPROVING WELLBEING
Not Important Somewhat Important Very Important Essential Mindfulness ( 20. All these components, and combinations of them, are considered to be beneficial for reducing anxiety.
The first questionnaire also asked participants to rate the importance of each component.
Using a rating scale from 1=not recommended to 5=essential, these components of yoga practice for reducing anxiety were rated by participants as either "very important" or "essential" as follows: 1st: Relaxation (95% of participants, with an "importance" rating of 4.5) 2nd: Regulation of Breathing (pranayama) (89% of participants, "importance" rating of 4.3) 3rd: Meditation (84% of participants, "importance" rating of 4.1) 4th: Postures (asana) (63% of participants, "importance" rating of 3.9) Do you agree with this overall rating of the relative importance of these components of yoga for reducing ANXIETY?
21. There was general consensus that this order of relative importance would be the same for using yoga to increase positive emotion and wellbeing in people with anxiety.