UIC	Urinary iodine concentration
HPT	Hypothalamic–pituitary–thyroid
TSHR	Thyroid stimulating hormone receptor
NKX2-1	NK2 homeobox 1
TTF-1	Thyroid transcription factor 1
TPO	Thyroid peroxidase
TG	Thyroglobulin
DUOX2	Dual oxidase 2
DNA	Deoxyribonucleic acid
SNPs	Single nucleotide polymorphisms
PCR	Polymerase chain reaction
TJCDC	Tianjin Centers for Disease Control and Prevention
BMI	Body mass index
UNICEF	United Nations Children’s Fund
IGN	Iodine Global Network
FT3	Free triiodothyronine
FT4	Free thyroxine
TSH	Thyroid-stimulating hormone
1st-PCRP	First PCR primer
2nd-PCRP	Second PCR primer
RCS	Restricted cubic spline
OR	Odds ratio
95% CI	95% confidence interval
GEE	Generalized estimating equations
AIC	Akaike Information Criterion
PR	Prevalence ratio
RERI	Relative excess risk due to interaction
AP	Attributable proportion
S	Synergy index
VIF	Variance inflation factor
TPOAb	Thyroid peroxidase antibody
TgAb	Thyroglobulin antibody