Table 2

 Subgroups of results from randomised controlled trials in adults

Subgroup factor, groupEffect size in kg (95% CI)No of comparisons, I2 (%)
Overall analysis: all arms−1.57 (−1.97 to −1.16)27, 75
Study duration (months):
 6-11−1.75 (−2.28 to −1.22)13, 63
 12-23−2.00 (−2.51 to −1.48)17, 71
 24-59−1.18 (−1.65 to −0.70)9, 56
 ≥60−0.68 (−1.66 to 0.29)4, 58
Control group fat intake (% energy):
 >35−1.20 (−1.62 to −0.78)11, 64
 >30-35−1.06 (−1.96 to −0.17)10, 69
 >25-30−2.97 (−3.60 to −2.33)5, 1
Participant sex:
 Men−2.74 (−4.32 to −1.17)4, 76
 Women−1.42 (−1.93 to −0.92)16, 70
 Mixed−1.27 (−2.08 to −0.47)7, 75
Publication decade:
 1960s−4.10 (−8.06 to −0.14)1
 1970sNo trials
 1980s−0.91 (−1.80 to −0.01)3, 0
 1990s−1.94 (−2.57 to −1.31)16, 77
 2000s−0.95 (−1.57 to −0.33)7, 72
Fat intake goal in intervention group (% energy):
 ≥35No data
 30-34−0.96 (−1.66 to −0.26)3, 0
 25-29−2.39 (−3.82 to −0.97)6, 87
 20-24−0.85 (−1.13 to −0.57)6, 14
 15-19−1.28 (−2.19 to −0.37)7, 58
Difference in fat intake between intervention and control (% energy):
 ≤5−0.19 (−0.88 to 0.50)6, 19
 5-9−2.08 (−2.77 to −1.39)13, 82
 10-14−1.34 (−1.70 to −0.98)4, 26
 ≥15−3.89 (−8.76 to 0.99)3, 68
Fat intake in intervention (control >30% energy):
 >30−0.83 (−1.29 to −0.38)6, 0
 ≤30−1.20 (−1.69 to −0.72)15, 74
Baseline body mass index:
 <25−0.96 (−1.69 to −0.22)8, 56
 25-29−1.82 (−2.37 to −1.28)16, 82
 ≥30−2.06 (−2.96 to −1.17)2, 0
Baseline health status:
 Healthy−0.98 (−1.56 to −0.41)3, 87
 Risk factors−2.11 (−2.93 to −1.29)15, 74
 Illness−1.20 (−1.85 to −0.56)9, 44
Energy intake* in reduced fat group compared with control:
 Same or greater−0.51 (−1.49 to 0.49)4, 25
 4-418 kJ/day lower−1.49 (−2.92 to −0.06)4, 66
 419-837 kJ/day lower−1.14 (−2.24 to −0.04)5, 80
 >837 kJ/day lower−2.15 (−2.78 to −1.52)11, 77

*418 kJ=100 kcal.