Table 3.

Quality assessment of included cohort and cross-sectional studies using the NIH quality assessment tool.

Author, YOP	Q1	Q2	Q3	Q4	Q5	Q6	Q7	Q8	Q9	Overall Quality
Jiramongkolchai et al. [8]	Y	Y	Y	Y	Y	Y	Y	Y	Y	Good
Govetto et al. [6]	Y	Y	Y	Y	Y	Y	Y	Y	Y	Good

Quality was rated as poor (if a study scored 0–3 out of 9 questions), fair (if a study scored 4–6 out of 9 questions), or good (if a study scored 7–9 out of 9 questions).

YOP year of publication, Y yes, N no, NR not reported.

Q1: Was the study question or objective clearly stated? Q2: Was the study population clearly and fully described, including a case definition? Q3: Were the cases consecutive? Q4: Were the subjects comparable? Q5: Was the intervention clearly described? Q6: Were the outcome measures clearly defined, valid, reliable, and implemented consistently across all study participants? Q7: Was the length of follow-up adequate? Q8: Were the statistical methods well-described? Q9: Were the results well-described?