Table 2.

Measured mean TSH, FT4, T4, T3, FT3 values at beginning and end of trials for monotherapy vs. combination therapy groups in trials grouped according to whether patients were estimated to have high RTF (>20%), medium RTF (10–20%), or low RTF (<10%).

Trial	TSH before	TSH end	FT4 (ng/dl) before	FT4 end	T3 (ng/dl) before	T3 end	FT3 (pg/dl) before	FT3 end	T3 & $\text{T}4$ ranges by sim	LT3 dose (μg)	LT4 dose (μg)
High RTF (>20%)
Appelhof T4	1.0	0.64	1.15	1.18	111	111	–	–	–
Appelhof T4 + T3 (10:1)	1.1	0.35	1.15	1.02	109	119	–	–	Med $\text{Med}$	7.5	75
Appelhof T4 + T3 (5:1)	1.0	0.07	1.18	1.00	115	143	–	–	Med-$\text{High}\text{Med}$	12.5	75
Bunevicius, 2002, T4	1.02	0.45	1.61	1.64	–	227	–	–	–
Bunevicius, 2002, T4 + T3	1.02	0.47	1.61	0.96	–	247	–	–	High $\text{High}$	10	65
Escobar-Morreale T4	nl	1.95	–	1.61	–	–	–	332	–
Escobar-Morreale T4 + T3 (5 μg)	nl	2.56	–	1.31	–	–	–	325	Med $\text{Med}$	5	75
Escobar-Morreale T4 + T3 (7.5 μg)	nl	1.09	–	1.34	–	–	–	384	Med $\text{Med}$	7.5	87.5
Siegmund T4	1.72	1.5	1.72	1.62	–	–	332	294	-
Siegmund T4 + T3	1.72	0.5	1.72	1.56	–	–	332	324	Low- Med $\text{High}$	6.5	123
Medium RTF (10–20%)
Clyde T4	2.2	2.1	1.2	1.2	96	87	–	–	–
Clyde T4 + T3	2.6	2.0	1.3	0.8	89	135	–	–	Med $\text{Med}$	15	86
Fadeyev T4	–	1.35	–	1.45	–	–	–	273
Fadeyev T4 + T3	–	1.7	–	0.96	–	–	–	267	Med $\text{Med}$	12.5	75
Kaminski T4	0.31	0.19	1.26	1.64	93	103	–	–	–
Kaminski T4 + T3	0.31	0.64	1.26	1.03	93	98	–	–	Med -High $\text{Med}$	15	75
Sawka T4	2.2	1.7	1.30	1.38	–	–	280	286	–
Sawka T4 + T3	1.75	1.8	1.22	0.82	–	–	267	306	Med Low	19	67
Rodriguez T4	1.7–1.8	2.5–2.9	$\mathrm{11}–\mathrm{11.2}$	$\mathrm{10.8}–\mathrm{10.9}$	76–79	73–86	–	–	–
Rodriguez T4 + T3	1.7–1.8	3.3–7.6	$\mathrm{11}–\mathrm{11.2}$	$\mathrm{7.6}–\mathrm{8.2}$	76–79	95–104	–	–	Med $\text{Med}$	10	71
Low RTF (<10%)
Bunevicius, 1999, T4	0.3	0.8	2.0	2.3/15.2	–	87	–	–	–
Bunevicius, 1999, T4 + T3	1.	0.5	1.9	1.8/11.3	–	117	–	–	High $\text{Med-High}$	12.5	125
Nygaard* T4	1.1	0.99	–	–	–	–	–	–	–
Nygaard* T4+T3	1.1	0.76	–	–	–	–	–	–	High Low	20	77
Saravanan T4	0.87	0.79	1.62	1.57	–	–	248	234	-
Saravanan T4 + T3	0.85	1.25	1.64	1.14	–	–	248	239	Med $\text{Med-High}$	10	77
Walsh T4	1.4	1.5	1.19	1.21	–	–	221	241	-
Walsh T4 + T3	1.4	3.1	1.19	0.89	–	–	221	228	Low-Med $\text{Med}$	10	86

Gray shading indicates T4/T3 arm of study,

^*study reports only free T4 index and FT3 index and does not report either total or free T4 or T3, blue font is total T4 levels in mcg/dL.

“T3 and T4 levels by sim” are the levels predicted by simulation for the combination therapy group, rather than measured T3 and T4 levels, and are categorized into 3 groups (high/medium/low). Mean/median LT3 and LT4 doses in the combination therapy group are also shown.