Because of the influence of subjects’ poor compliance

failure to record the combined drugs and other factors

it is difficult to make quality control during the large sample multicenter

randomized

double-blind controlled trials of Chinese Medicine treatment of cold

which finally will affect the authenticity and scientific nature of the study results. To ensure research implementation quality

in a multicenter

randomized

double-blind controlled trial including 3000 cases of cold treated with antiviral oral liquid

the quality control method of field distance interaction was adopted. The advantage of field quality control was researchers（ implementation interveners and effect evaluators） and subjects could meet face to face. Thus it was appropriate to develop interview of research related personnel and to study the information origins. The advantage of distance quality control was real-time. Quality control personnel could know study progress

adverse events and other situations by distance quality control instantly and meanwhile adjust check frequency of field quality control according to evaluation results of distance quality control

so that to save quality control cost

and at the same time ensure research quality. The content and methods of quality control did well control the quality of research

and it provided references for quality control in randomized controlled trials of Chinese Medicine treatment of cold.