TABLE 1.

Effect of study design aspects (effect modifiers) on heterogeneity in TEE outcome among 29 trials comparing lower- and higher-carbohydrate diets¹

Modifiers	P	Qres2	I2res,3 %	τ2 remaining4	R 2,5 %
Overall (no modifier)	—	124.2	81.6	6036	—
Univariate
Study duration	<0.001	84.7	65.9	2586	57.2
Difference in carbohydrate	0.001	82.1	71.8	3534	41.5
TEE method6	0.004	103.6	73.4	3660	39.4
Multivariate
Study duration	<0.001	54.3	51.0	1420	76.5
Difference in carbohydrate	0.002
Study duration	<0.001	84.1	67.1	2659	56.0
TEE method	0.919
Difference in carbohydrate	<0.001	56.3	46.4	1173	80.6
TEE method	<0.001
Study duration	0.011	49.7	46.2	1141	81.1
Difference in carbohydrate	0.001
TEE method	0.130

¹TEE, total energy expenditure.

² is Cochran's Q statistic for heterogeneity remaining after effect modifiers included.

³ is the percentage of variation across studies due to heterogeneity remaining after modifiers included.

⁴τ² is the between-study variability remaining after modifiers included.

⁵ R ² is the percentage of variability (τ²) explained by the modifiers in each model.

⁶Whole-room calorimetry vs doubly labeled water.