Footnotes

• Collaborators Members of GAIN Group (in alphabetical order)- All India Institute of Medical Sciences, New Delhi, India: Ashish Agarwal, Samagra Agarwal, Vineet Ahuja, Abhinav Anand, Rajat Bansal, Vikas Banyal, Kaushik Chatterjee, Anugrah Dhooria, Anshuman Elhence, Pramod Garg, Srikanth Gopi, Deepak Gunjan, Yegurla Jatin, Vikas Jindal, Bhaskar Kante, Kanav Kaushal, Saurabh Kedia, Soumya Jagannath Mahapatra, Govind Makharia, Srikant Mohta, Sandeep Kumar Mundhra, Piyush Pathak, Shubham Prasad, Mahendra Singh Rajput, Atul Rana, Anoop Saraya, Pabitra Sahu, Rahul Sethia, Shalimar, Sanchit Sharma, Amit Anurag Singh, Manas Vaishnav, Sudheer Kumar Vuyurru. Post Graduate Institute of Medical Educations and Research, Chandigarh, India: Usha Dutta, Rakesh Kochhar, Harshal S Mandavdhare, Gaurav Muktesh, Praveer Rai, Jayanta Samanta, Vishal Sharma, Jayendra Shukla. Christian Medical College, Vellore, India: Kaushik Chatterjee, Sudipta Dhar Chowdhury, Amit Kumar Dutta, John Titus George, Rajeeb Jaleel, Anjilivelil Joseph, Ebby George Simon. Sanjay Gandhi Post Graduate Institute, Lucknow, India: Ptaviva Chandra, Samir Mohindra, Vivek Saraswat, Jimil Shah. Gobind Ballabh Pant Hospital, New Delhi, India: Roshan George, Arpan Jain, Anurag Mishra, Sanjeev Sachdeva, Alok Kumar Singh.

• Contributors SJ, AA, DG, SDC, VS, SS, RK and AS: study design, critical inputs, collection of data and manuscript writing. SM, VS and other members of GAIN study group: collection of data.

• Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

• Competing interests None declared.

• Provenance and peer review Not commissioned; externally peer reviewed.

• Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.