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. 2012 Dec 12;2012(12):CD008650. doi: 10.1002/14651858.CD008650.pub2

1. Overview of study populations.

Characteristic
Study ID 		Intervention(s) and 
 control(s) [N] screened [N] randomised [N] safety [N] ITT [N] finishing study [%] of randomised participants 
 finishing study
Auvichayapat 2008 1 
 (weight loss study) I1:   green tea extract
C1: placebo		 I1: ‐
C1: ‐
T: 73		 I1: 30
C1: 30
T: 60		 I1: 30
C1: 30
T: 60		 ‐ I1: 30
C1: 30
T: 60		 I1: 100
C1: 100
T: 100
Diepvens 2005 
 (weight loss study) I1: green tea
C1: placebo		 I1: ‐
C1: ‐
T: 57		 I1: 23
C1: 23
T: 46		 I1: 23
C1: 23
T: 46		 ‐ I1: 23
C1: 23
T: 46		 I1: 100
C1: 100
T: 100
Hill 2007 
 (weight loss study) I1: green tea extract
C1: placebo		 ‐ I1: ‐
C1: ‐
T: 42		 I1: ‐
C1: ‐
T: 42		 ‐ I1: 19
C1: 19
T: 38		 I1: ‐
C1: ‐
T: 91
Hsu 2008 
 (weight loss study) I1: green tea extract
C1: placebo		 I1: ‐
C1: ‐
T: 336		 I1: 50
C1: 50
T: 100		 ‐ ‐ I1: 41
C1: 37
T: 78		 I1: 82
C1: 74
T: 78
Hursel 2009 
 (weight maintenance study) I1: green tea‐caffeine mixture + AP diet
I2: green tea‐caffeine mixture + HP diet
C1: placebo + AP diet
C2: placebo + HP diet		 I1: ‐
I2: ‐
C1: ‐
C2: ‐
T: 100		 I1: 20
I2: 20
C1: 20
C2: 20
T: 80		 I1: 20
I2: 20
C1: 20
C2: 20
T: 80		 ‐ I1: 20
I2: 20
C1: 20
C2: 20
T: 80		 I1: 100
I2: 100
C1: 100
C2: 100
T: 100
Kajimoto 2005 
 (weight loss study) I1: catechin drink – low‐dose group
I2: catechin drink – high‐dose group
C1: placebo drink		 ‐ I1: ‐
I2: ‐
C1: ‐
T: 197		 I1: ‐
I2: ‐
C1: ‐
T: 197		 ‐ I1: 65
I2: 64
C1: 66
T: 195		 I1: ‐
I2: ‐
C1: ‐
T: 99
Kataoka 2004 
 (weight loss study) I1: catechin beverage 278 mg
I2: catechin beverage 570 mg
I3: catechin beverage 845 mg
C1: control
beverage		 ‐ I1: 25
I2: 71
I3: 25
C1: 71
T: 192		 I1: 25
I2: 71
I3: 25
C1: 71
T: 192		 ‐ I1: 25
I2: 71
I3: 25
C1: 71
T: 192		 I1: 100
I2: 100
I3: 100
C1: 100
T: 100
Kovacs 2004 2 
 (weight maintenance study) I1: green tea
C1: placebo		 I1: ‐
C1: ‐
T: 140		 I1: ‐
C1: ‐
T: 120		 I1: 51
C1: 53
T: 104		 ‐ I1: 51
C1: 53
T: 104		 I1: ‐
C1: ‐
T: 87
Kozuma 2005 3 
 (weight loss study) I1: catechin beverage
C1: placebo beverage		 I1: ‐
C1: ‐
T: 254		 I1: ‐
C1: ‐
T: 234		 I1: ‐
C1: ‐
T: 234		 ‐ I1: 107
C1: 119
T: 226		 I1: ‐
C1: ‐
T: 97
Maki  2009 4 
 (weight loss study) I1: green tea beverage
C1: control beverage		 I1:‐
C1:‐
T: 337		 I1: 67
C1: 65
T: 132		 I1: 66
C1: 63
T: 129		 I1: 65
C1: 63
T: 128		 I1: 56
C1: 51
T: 107		 I1: 84
C1: 79
T: 81
Nagao 2007 
 (weight loss study) I1: brewed green tea beverage with added catechins
C1: brewed green tea beverage with no added catechins		 ‐ I1: 135
C1: 135
T: 270		 ‐ ‐ I1: 123
C1: 117
T: 240		 I1: 91
C1: 87
T: 89
Suzuki 2009 
 (weight loss study) I1: tea catechin
C1: placebo		 ‐ I1: 20
C1: 21
T: 41		 ‐ ‐ I1: 18
C1: 20
T: 38		 I1: 90
C1: 95
T: 93
Takase 2008 5 
 (weight loss study) I1: catechin beverage
C1: placebo beverage		 ‐ I1: 49
C1: 52
T: 101		 I1: 48
C1: 46
T: 94		 ‐ I1: 46
C1: 47
T: 93		 I1: 94
C1: 90
T: 92
Takashima 2004 
 (weight loss study) I1: catechin beverage
C1: control beverage		 ‐ I1: 10
C1: 9
T: 19		 I1: 10
C1: 9
T: 19		 ‐ I1: 10
C1: 9
T: 19		 I1: 100
C1: 100
T: 100
Takeshita 2008 
 (weight loss study) I1: catechin beverage
C1: placebo beverage		 ‐ I1: 40
C1: 41
T: 81		 I1: 40
C1: 41
T: 81		 ‐ I1: 40
C1: 41
T: 81		 I1: 100
C1: 100
T: 100
Tsuchida 2010 
 (weight loss study) I1: catechin beverage
C1: control beverage		 ‐ I1: 39
C1: 41
T: 80		 I1: 39
C1: 41
T: 80		 ‐ I1: 39
C1: 41
T: 80		 I1: 100
C1: 100
T: 100
Wang 2010 6 
 (weight loss study) I1: green tea 1
I2: green tea 2
I3: green tea 3
C1: control drink		 I1: ‐
I2: ‐
I3: ‐
C1: ‐
T: 435		 I1: ‐
I2: ‐
I3: ‐
C1: ‐
T: 205		 ‐ ‐ I1: ‐
I2: ‐
I3: ‐
C1: ‐
T: 192		 I1: ‐
I2: ‐
I3: ‐
C1: ‐
T: 94
Westerterp‐Plantenga 2005 
 (weight maintenance study) I1: green tea‐caffeine capsule ‐ low habitual caffeine consumers
I2: green tea‐caffeine capsule ‐ high habitual caffeine consumers
C1: placebo ‐ low habitual caffeine consumers
C2: placebo ‐ high habitual caffeine consumers		 I1: ‐
I2: ‐
C1: ‐
C2: ‐
T: 90		 I1: 19
I2: 19
C1: 19
C2: 19
T: 76		 I1: 19
I2: 19
C1: 19
C2: 19
T: 76		 ‐ I1: 19
I2: 19
C1: 19
C2: 19
T: 76		 I1: 100
I2: 100
C1: 100
C2: 100
T: 100
Total7 Weight loss studies   1800   1685  
  Weight maintenance studies 276 260
  All studies 2076 1945

"‐" denotes not reported. 
 1 all participants were Khon Kaen University officers. 
 2 this was a two‐part study. Participants were given special diet (not including green tea) to lose weight for four weeks. They were then given green tea to see if it would help maintain weight loss. Sixteen participants dropped out during very‐low‐energy diet period before ever receiving the intervention or placebo. 
 3 254 participants "gave informed consent" – it is not clear if this was the actual number screened, but we think so. 
 4 this study's usage of ITT differs from the Cochrane definition. 
 5 "of these individuals, four whose insulin levels recorded at week 0 were abnormal (two in the placebo group and two in the catechin group) were excluded from analysis, leaving a group suitable for analysis of 45 individuals in the placebo group and 44 individuals in the catechin group." 
 6 although 192 completed the study 10 participants were excluded from analysis for various reasons; thus analysis was carried out for 182 participants. 
 7 not all studies specified how many participants were randomised into each group at the start, though totals are available for each study. In one case (Wang 2010), the number of participants in each group at the end of the study was also not given, though the total number of participants finishing was given.

C: control; I: intervention; ITT: intention to treat; T: total.