Fig. 1.

Efficacy of Chinese herbal medicine (CHM) compared with α2-adrenergic agonists (A), and opioid agonists (B) in alleviating opioid-withdrawal symptoms. Summary estimates of the weighted mean differences (WMDs) and their 95% CIs are given day by day. D0 indicates pretreatment baseline. D0, D5, D6, D9, D10 in (A) and D0, D1, D2 in (B) were analyzed in fixed-effects models. The other time points were analyzed in random-effects models. N_R indicates the fail-safe number, i.e. the number of unpublished negative studies that would be required to overturn each significant finding at an alpha level of 0.05