The principal author and four co-authors declare that they have no competing interests.

ST conceived and designed the study and prepared the manuscript. NKV participated in the conception and design of the study and in compiling the manuscript. MD co-ordinated the project and supervised the intervention and data collection. RD participated in the recruitment of subjects, data collection and assisted in statistical analysis. MNK carried out data extraction and analysis. All authors read and approved the final manuscript.

The research was funded by the Central Council for Research in Yoga and Naturopathy, Department of AYUSH, Ministry of Health and Family Wel- fare, Government of India, New Delhi, India.

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