To analyze the difference between bilateral P25 peak latencies by t test.To obtain the 95% normal reference values of the difference between bilateral P25 peak latencies.

• 计算52例受试者的P25峰潜伏期的双侧95%25测定值范围，用配对t检验分析受试者双侧P25峰潜伏期是否存在差异，得出双侧P25峰潜伏期差值的单侧95%25测定值范围。