Table 1 Characteristics of the included studies
Characteristics | Participants | Intervention | Comparison | Outcome | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Source | Study design | Country | Jadad score | Diagnosis | Age/Case no | Female No.(%) | DLX | PLC | Primary outcome | DLX | PLC | Drop-out rate, % | Severe AE DLX/PLC, No |
Case no./dose/frequency/duration | Case no./dose/frequency/duration | Baseline pain score, Mean ± SE | |||||||||||
Gao et al., 2015 [40] | Double-blind, RCT | China | 3 | 1. Daily pain > 6 mos 2. Michigan score ≥ 3 3. BPI weekly pain ≥ 4 | 61.4/405 | 223 (55.1%) | 203/60 mg/QD/12 wks | 202/PLC/QD/12 wks | Weekly mean 24-h avg. pain score | 5.7 ± 1.7 | 5.6 ± 1.7 | 13.80% | 3/2 |
Rowbotham et al., 2012 [39] | Double-blind, rct | USA | 5 | 1. Daily pain > 6 mos 2. Michigan score ≥ 3 3. Weekly 24-h pain score ≥ 4 | 59.9/108 | 48 (44.4%) | 57/60 mg/QD/8 wks | 51/PLC/QD/8 wks | Weekly mean 24-h avg. pain score | 6.61 ± 1.37 | 6.62 ± 1.23 | - | 1/1 |
Gao et al., 2010 [38] | Double-blind, rct | China | 4 | 1. Daily pain > 6 mos 2. Michigan score ≥ 3 3. Weekly 24-h pain score ≥ 4 | 59.3,215 | 114 (53.0%) | 109/60 mg or 120 mg/QD/12 wks | 106/PLC/QD/12wks | BPI avg. pain | 5.5 ± 1.3 | 5.5 ± 1.4 | 13.60% | 2/2 |
Yasuda et al., 2011 [34] | Double-blind, rct | Japan | 4 | 1. Daily pain > 6 mos 2. DSPN diagnostic criteria in Japan | 60.8/338 | 82 (24.3%) | 40 mg: 85/40 mg/QD/12 wks | 167/PLC/QD/12 wks | Weekly mean 24-h avg. pain score | 40 mg: 5.79 ± 1.23 | 5.78 ± 1.17 | 16.70% | 5/6 |
60 mg: 86/60 mg/QD/12 wks | 60 mg: 5.76 ± 1.17 | ||||||||||||
Double-blind, RCT | USA | 5 | 1. Daily pain > 6 mos 2. Michigan score ≥ 3 3. Weekly 24-h pain score ≥ 4 | 60.7/334 | 130 (38.9%) | 60 mg: 114/60 mg/QD/12 wks | 108/PLC/QD/12 wks | Weekly mean 24-h avg. pain score | 60 mg: 6.1 ± 1.6 | 5.9 ± 1.4 | 25.70% | 7/5 | |
120 mg: 112/60 mg/BID/12 wks | 120 mg: 6.2 ± 1.5 | ||||||||||||
Raskin et al., 2005 [36] | Double-blind, RCT | Canada | 5 | 1. Daily pain > 6 mos 2. Michigan score ≥ 3 3. Weekly 24-h pain score ≥ 4 | 58.8/348 | 186 (53.4%) | 60 mg: 116/60 mg/QD/12 wks | 116/PLC/QD/12 wks | Weekly mean 24-h avg. pain score | 60 mg: 5.5 ± 1.1 | 5.5 ± 1.3 | 15% | 6/4 |
120 mg: 116/60 mg/BID/12 wks | 120 mg: 5.7 ± 1.3 | ||||||||||||
Goldstein et al., 2005 [37] | Double-blind, RCT | USA | 5 | 1. Daily pain > 6 mos 2. Michigan score ≥ 3 3. Weekly 24-h pain score ≥ 4 | 60.1/457 | 176 (38.5%) | 20 mg: 115/20 mg/QD/12 wks | 115/PLC/QD/12 wks | Weekly mean 24-h avg. pain score | 20 mg: 5.9 ± 1.6 | 5.8 ± 1.5 | 24.70% | Total 19 |
60 mg: 114/60 mg/BID/12 wks | 60 mg: 6.0 ± 1.7 | ||||||||||||
120 mg: 113/60 mg/BID/12 wks | 120 mg: 5.9 ± 1.4 | ||||||||||||