SD_from_CI {metaHelper} | R Documentation |
Standard Deviation from Confidence Interval
Description
Computes the standard deviation from the confidence interval and sample size. This method is valid only for single groups and assumes the confidence interval is symmetrical around the mean. For two groups (e.g., intervention effects), use SDp_from_CIp()
. For sample sizes smaller than 60, the t-distribution (parameter "t-dist") is typically used to calculate the confidence interval.
Usage
SD_from_CI(CI_low, CI_up, n, sig_level = 0.05, two_sided = TRUE, t_dist = TRUE)
Arguments
CI_low |
lower limit confidence interval |
CI_up |
upper limit confidence interval |
n |
sample size |
sig_level |
significance level |
two_sided |
whether a two sided test for significance was used |
t_dist |
whether a t-distribution has been used to calculate the CI. See description. |
Value
Standard deviation single group
References
See Also
SDp_from_CIp()
for two groups (e.g. intervention effects).
Examples
# lower CI = -0.5, upper CI = 2, sample size = 100
SD_from_CI(-05, 2, 100)
[Package metaHelper version 1.0.0 Index]