All data were collected through direct interview. The gathered data were analyzed by methods of matched and unmatched studies in IBM computer, and expressed by odds ratio (OR).
直接面询收集的资料用IBM微机处理，主要用成组和非成组分析方法计算比数比(OR值)。
2
On the bases of the work of a superposed energy type ignition system and its circuits analysis, a series of experimental studies on the matched engine have been done.
在能量叠加点火系电路分析的基础上，对其进行了匹配发动机的试验研究。
3
The other two studies examined the cancer risk and smoking habits of current and former smokers, with and without cancer, with a carefully matched control group of never-smokers.