计算SD(Calculate SD)
通过标准误(SE)计算标准差(SD)
SD = SE * sqrt(n)
通过组内95%置信区间(CI)估算SE时,上述公式变换为(n>60):
SD = ((CIUpper - CILower)/3.92) * sqrt(n)
附:通过中位数(Medians)和四分位数(Quartile)估算均数和标准差
若数据符合正态分布,可以直接用中位数代替均数,标准差通过下式估算。
SD = (75th percentile - 25th percentile)/1.35
Go Top
两组合并(Combining two groups)
二分类数据(For Binary data):各组样本量和事件数分别相加。 Add up sample_size and event_number of each group separately.
连续型数据(For Continuous data): 通过下表计算 as follow
Go Top
拆分组(Splitting group)
二分类数据(For Binary data):样本量和事件数分别除以组数后取整。The sample size and the number of events were divided by the number of groups and then rounded them up.
连续型数据(For Continuous data):样本量除以组数后取整,均值和标准差不变。 The sample size is divided by the number of groups and then rounded, the mean and standard deviation remain unchanged.
Go Top