病证首选和常用药对的筛选已成为挖掘古代方药学遗产的侧重点。本文在常用的逻辑分析和频次判断方法之外，利用《普济方》数据库管理系统，以头痛及相类病证的用药情况为示范，建立药物组合使用率的卡方检验比较分析方法，借以确定古代病证首选和常用药对，提供一种定性与定量相结合的药对分析判断方法。但当借鉴由此获取的药对时，尚需结合现代临床经验做出综合判断。

The screening of primary choice and commonly-used paired herbs of symptoms become the focus of mining heritage of the ancient medicine. In this paper, besides the using of logical analysis and the frequency determination method, Pu Ji Fang Database Management System was also used. Drug use for headache and its similar symptoms was used as a model. The comparative analysis of chi-square test was established for utilization rate determination of drug combinations. This method provides a qualitative and quantitative method to determine paired herbs and may help us determine primary choice and commonly-used paired herbs of ancient symptoms. When referring to paired herbs results given by this method, comprehensive determination should be made in combination with modern clinical experiences.