Quality assessment of study design (rigor score^*).

*One point score for meeting each of the following items (if data were not available in the articles for any item, 0.5 was recorded): (a)was a prospective cohort, (b)used a comparison arm, (c)collected pre and post intervention data, (d)used random assignment of participants to study arms, (e)did random sampling for assessments, (f)sample size >100, (g)follow-up rate ≥80%, (h)had a comparison group with comparable socio-demographics such as age, education, race, employment, income, marital status and others [score “1” if >50% variables were comparable between study arms, and ‘0’ if not], and (i)had a comparison arm with comparable outcome measures at baseline between study arms.