Table 2. Iodine concentrations in all groups.

Characteristic	Overall	PTC group	NTG group	Healthy control group
Excessive iodine intake (N / percent)	51/29	23/43*	22/37*	6/9
Non-excessive iodine intake (N / percent)	127/71	30/57	38/63	59/91
Urinary iodine (ng/ml)
Range	142.90–1409.90	169.52–1409.90	144.10–1007.60	142.90–433.70
GM	268.25	319.66*	273.34*	228.51
Median	252.45	289.60	271.30	230.20
P25	215.33	240.20	198.30	184.20
P75	325.52	399.10	357.83	266.60
Creatinine (g/l)
Range	0.10–3.24	0.20–2.66	0.11–2.24	0.10–2.24
GM	0.80	0.87	0.64	0.64
Median	0.85	0.94	0.70	0.70
P25	0.53	0.58	0.43	0.56
P75	1.35	1.31	1.07	1.59
Urinary iodine/creatinine (μg/g)
Range	71.25–2995.74	94.85–2149.31	77.86–2995.74	71.25–2130.37
GM	335.05	368.71*	426.02*	248.26
Median	316.69	355.72	386.25	230.94
P25	193.57	194.63	260.34	148.57
P75	551.65	632.14	658.60	396.84

^*P<0.05, there is statistical difference compared with the healthy control group.