Table 4. Characteristics of the 10 included studies on leptin.
| BMI (mean ± SD) | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Author | Year | Country | Sample size | Age (mean ± SD) | Pre-Met | Post-Met | Inclusion/exclusion criteria | Study design | LOE | Therapy duration (month) | Daily dose (mg) |
| Kowalska I [30] | 2001 | Poland | 11 | 27.7 ± 1.3 | 34.9 ± 5.6 | 31.4±4.8 | H | SCT | 2 | 4–5 | 1500 |
| Luque RM [32]A | 2008 | Spain | 10 | 23 ±5 | 25.0 ± 2.8 | NR | H | SCT | 2 | 3 | 850 |
| Luque RM [32]B | 2008 | Spain | 9 | 27 ± 8 | 36.6 ± 4.4 | NR | H | RCT | 1 | 3 | 850 |
| Maciel GA [33] | 2003 | Brazil | 7 | 22.5 ± 1.9 | 25.3 ± 2.1 | 24.9±2.7 | H | RCT | 1 | 6 | 1500 |
| Marciniak A [34] A | 2009 | Poland | 23 | NR | 30.86 ± 5.35 | 30.39±6.1 | H | SCT | 2 | 3 | 1700 |
| Marciniak A [34] B | 2009 | Poland | 12 | NR | 20.99 ± 1.87 | 20.75±1.79 | H | SCT | 2 | 3 | 1700 |
| Moran L J [35] | 2010 | Australia | 29 | 33.5±6.7 | 36.1 ± 7.2 | NR | H | SCT | 2 | 6 | 2000 |
| Morin PL [36] A | 2003 | Finland | 8 | 28.2±1.4 | 22.5 ± 0.8 | 21.7±0.7 | H | RCT | 1 | 3 | 1000 |
| Morin PL [36] B | 2003 | Finland | 8 | 28.2 ±1.4 | 22.5 ± 0.8 | 22.1 ± 0.8 | H | RCT | 1 | 6 | 2000 |
| Morin PL [37] A | 1998 | Finland | 26 | 30 ± 6.8 | 31 ± 4.6 | 30.66± 4.7 | H | SCT | 2 | 2 | 1500 |
| Morin PL [37] B | 1998 | Finland | 12 | NR | 31 ± 4.6 | 31.7±6 5.4 | H | SCT | 2 | 4–6 | 1500 |
| Ng E H [38] | 2001 | China | 8 | 30.5 | 24.1 | NR | H | RCT | 2 | 3 | 1500 |
| Maria M [39] | 2011 | Bulgaria | 32 | 23.58±4.17 | 28.45±4.38 | 27.45±3.73 | H | SCT | 2 | 3 | 1275 |
| Romualdi D [41] | 2008 | Italy | 7 | 23.57±6.97 | 32.64±4.35 | 31.64±3.15 | H | SCT | 2 | 4 | 1500 |
Abbreviations: SD, standard deviation; BMI, body mass index; NR, not reported; H, have; LOE, level of evidence; SCT, self-control trials; RCT, randomized controlled trials.