To detect the risk factots of LBW in medium altitude (2260 m),a case-control study was conduct in Xining during 1993. 6-1994. 12. The subjects of study consisted of 147 term LBW and their parents with 147 controls.

• 为了研究亚高原（2260米）LBW发病原因，我们于1993年6月一1994年12月对西宁市147对对象进行一次病例对照研究。