Table 6.

Multivariate analysis of predictors of a tumour-free clinical outcome.

Parameters	OR	95%CI	P
Sex
Male	1
Female	0.355	0.111–1.135	0.081
Surgery
TT+ central neck lymph node dissection	1
TT+ central and lateral neck lymph node dissection	0.677	0.139–3.288	0.628
Extrathyroidal extension
No invasion	1
Microscopic	1.703	0.097–29.976	0.716
Macroscopic	0.890	0.061–13.048	0.932
T
T1	1
T2	0.016	0.000–0.876	0.043
T3	0.060	0.001–3.207	0.166
T4	0.247	0.012–5.162	0.367
N
N0	1
N1a	0.820	0.100–6.732	0.854
N1b	1.120	0.212–5.925	0.894
Initial risk stratification
Low risk	1
Intermediate risk	0.283	0.025–3.234	0.310
High risk	0.461	0.124–1.712	0.247
The variation of TgAb relative to preoperative level
Before 131I therapy <−63.4%	1
Before 131I therapy ≥−63.4%	0.600	0.193–1.865	0.377
6 months after 131I therapy <−77.9%	1
6 months after 131I therapy ≥−77.9%	3.098	0.975–9.845	0.055
1 year after 131I therapy <−77.4%	1
1 year after 131I therapy ≥−77.4%	4.875	1.651–14.395	0.004
2 years after 131I therapy <−88.6%	1
2 years after 131I therapy ≥−88.6%	9.919	3.185–30.885	<0.001

OR, odds ratio; TT, total thyroidectomy; TgAb, antithyroglobulin antibody.