Quality assessment
The same two researchers (NL and LX) independently rated all the research articles included in the systematic review using the American Dietetic Association Quality Criteria Checklist.16 The scientific soundness of the articles was rated using ten validity questions. Based on the answers, one of the three quality ratings was assigned: positive (answered “yes” to six or more validity questions, including four priority questions), negative (answered “no” to six or more validity questions), or neutral (the rest of the situations). Only articles with a positive or neutral quality rating were included in the meta-analysis.