Efficacy and safety of Qing-Feng-Gan-Ke Granules in patients with postinfectious cough: study protocol of a novel-design phase III placebo-controlled, double-blind randomized trial.

Efficacy and safety of Qing-Feng-Gan-Ke Granules in patients with postinfectious cough: study protocol of a novel-design phase III placebo-controlled, double-blind randomized trial.