Quality
appraisal
The risk of bias and the methodology quality of the identified
publications were assessed using the Newcastle-Ottawa Scale (NOS) for
cohort studies and a NOS adapted version for cross-sectional studies
[9]. NOS is a star-rating based system, with a maximum of 9 scores
for cohort studies, randomized controlled trials and a maximum of 10
scores for cross-sectional studies. Each study’s quality is assessed
using the following grading algorithms: with a NOS score of 7 and above,
it is considered a high-quality study, studies with 4 to 6 points are
considered medium-quality, while those with 0 to 3 scores are considered
low-quality [10].