Table 4.

Physician Characteristics Affecting Physician Prescribing Continued LT4 Versus Increasing LT4 Versus Adding LT3 to LT4 Versus Replacing LT4 with T3-Containing Therapy

(A) Univariate analyses
Physician characteristic	Therapeutic options	Unadjusted odds ratio	Confidence interval		p-Value for model
Years in practice (in training = reference)
<5 years	1 vs. 2	2.2	0.77	6.3	0.041
	1 vs. 3	0.96	0.25	3.7
	1 vs. 4	5.5	0.95	32.2
5–10 years	1 vs. 2	2.3	0.83	6.3
	1 vs. 3	1.4	0.39	5.0
	1 vs. 4	3.2	0.57	18.1
11–20 years	1 vs. 2	3.6	1.4	9.6
	1 vs. 3	1.6	0.48	5.5
	1 vs. 4	5.1	0.96	26.8
>20 years	1 vs. 2	2.8	1.1	7.1
	1 vs. 3	0.8	0.25	2.6
	1 vs. 4	3.6	0.71	18.0

Country of practice (outside North America = reference)
North America	1 vs. 2	0.89	0.66	1.2	0.0088
	1 vs. 3	1.8	1.2	2.7
	1 vs. 4	1.6	0.95	2.6

Specialty (internist or primary care = reference)
vs endocrinologist, surgeon, nuclear medicine physician, other					0.24

(b) Multivariate analyses
Physician characteristic	Therapeutic options	Adjusted odds ratio	Confidence interval		p-Value for model
Years in practice (in training = reference)
vs. <5 years, 5–10 years, 11–20 years, >20 years					0.067
Country of practice (outside North America = reference)
North America	1 vs. 2	0.92	0.68	1.3	0.0073
	1 vs. 3	1.9	1.2	2.9
	1 vs. 4	1.7	1.0	2.9
Specialty (internist or primary care = reference)
vs. endocrinologist, surgeon, nuclear medicine physician, other					0.35

Significant comparisons are indicated in bold.

Continuing LT4 = therapeutic option 1 (reference); increasing LT4 = therapeutic option 2; adding LT3 to same or reduced LT4 = option 3; replacing LT4 with DTE or LT3 = option 4.