Table 3 Summary of risk of bias assessment based on Newcastle-Ottawa Quality Assessment for Cohort Studies. A filled star denotes that a star has been awarded and that a study has been graded high quality. A blank star denotes that no star has been awarded and that the study has been graded as poor quality in that category. Total score indicates the total number of stars awarded in all categories. N/A denotes not applicable

From: Malignancy risk of hyperfunctioning thyroid nodules compared with non-toxic nodules: systematic review and a meta-analysis