Assessment of risk of bias in included studies  
The Cochrane risk of bias tool version 1 was used to assess the risk of bias of the included studies by two review authors independently (VVR and KM)16. The risk of bias was evaluated based on the following five domains - selection bias, performance bias, detection bias, attrition bias, reporting bias, and other bias. Any disagreement between the reviewers was resolved by discussion or consultation with the third author (PBH).