Abstract: AIM: To develop a symptom scale for evaluating efficacy of the multi-enzyme combination capsule in treatment of patients with dyspepsia symptoms be caused digestive enzyme insufficient. METHODS: The symptom score is always related to the incidence rate (f requency), the importance (evaluated by experts) and the serious degree (light, moderate and serious) in a measuring scale, and a mathematical model was proposed to calculate the weight factor and its scores for each symptom in the scale.In an example of the multi-enzyme combination capsule in treatment of patients with chemical dyspepsia, the efficacy was analyzed based on the symptom scales with this approach.The scale was evaluated with the reliability, the validity, the responsibility to change, and the simulation. RESULTS: Six symptoms (epigastric distention, easy satiety, the degression of appetite, belches, counter-sour and nausea) were selected as indices, and their weight factors and grades were calculated in score scales.Some evaluations demonstrated that the approach showed a better feasibility, uniformity, and responsibility to change.The sample size (100-2 000) and the flutter (10%) of the importance and the frequency yielded a little effect on total scores in simulation. CONCLUSION: This is a reliable approach in developing a scale of symptomatology for evaluating efficacy of drugs.

Key words: multi-enzyme combination capsule, dyspepsia, scale, mathematical model, simulation, reliability, validity, the responsibility to change