Table 2.
Overview of Five Studies Included in the Systematic Review
| Study | Sample (n) | Duration | WS dosage | Control regimen | Outcome measures | Results | Risk of bias and threats to validity |
|---|---|---|---|---|---|---|---|
| Andrade et al., 200016 | 39 (15 female, 24 male) | 6 wk (42 d) | 1000 mg/d (250-mg per tablet); dose adjusted after wk 2 | Placebo twice per day | Primary: HAM Secondary: GRS, SAFTEE |
88.2% response in WS group vs. 50% in placebo group (p=0.026) | Risk of bias: high Inconsistent dosing; range of 2–10 tablets per day, small sample, short duration, 48.7% dropout rate |
| Auddy et al., 200817 | 130 (35 female, 95 male) | 60 d | 125 mg/d, 250 mg/d, 500 mg/d | Placebo twice per day | Primary: mHAM-A Secondary: biomarkers |
Significant dose-dependent decrease in mean sum mHAM-A score (p<0.001) | Risk of bias: unclear Reporting bias; conflicts of interest: 2 authors employed by funder (Natreon Inc.); 24.6% dropout rate |
| Cooley et al., 200918 | 81 (51 female, 30 male) | 12 wk (84 d) | 600 mg/d with counseling | PT: CBT+placebo | Primary: BAI Secondary: SF-36, FQ, MYMOP |
Final BAI scores decreased by 56.5% in NC group and 30.5% in PT group (p<.0001) Greater improvement in BAI for NC versus PT (p=0.003) |
Risk of bias: high Performance bias: care providers not blinded to participant distribution, lack of true control group, 21.0% dropout rate |
| Chandrasekhar et al., 201219 | 64 (23 female, 41 male) | 60 d | 600 mg/d after food and with water | Placebo twice per day | Primary: PSS Secondary: DASS, GHQ-28, cortisol |
Greater decrease in PSS (44.0% versus 5.5%; p<0.0001), GHQ-28 and DASS (p<0.0001), and cortisol (27.9% versus 7.9%; p=0.002) for WS versus placebo | Risk of bias: unclear Small sample size, 4.7% dropout rate |
| Khyati and Ayup, 201420 | 86 | 60 d | 12,000 mg/d taken with Anupana (milk) | Placebo thrice per day | Primary: HAM | Greater improvement in WS versus placebo in anxious mood (p<0.001) | Risk of bias: unclear Dropout rate not indicated |
Risk of bias assessed by using Cochrane Collaboration tool.
HAM, Hamilton Anxiety Scale; GRS, Global Rating Scale; SAFTEE, Systematic Assessment for Treatment Emergent Effects; mHAM-A, modified Hamilton Anxiety Scale; CBT, cognitive-behavioral therapy; BAI, Beck Anxiety Inventory; SF-36, Short Form 36; FQ, Fatigue Questionnaire; MYMOP, Measure Yourself Medical Outcomes Profile; NC, naturopathic care; PT, psychotherapy; PSS, Perceived Stress Scale; DASS, Depression Anxiety Stress Scale; GHQ-28, General Health Questionnaire 28.