Hi all,
I would like to calculate the 95% confidence interval of the slope for a thickness cluster (vs age in years) produced by mri_glmfit-sim.
I have obtained values for my clusters from gamma.mgh and gammavar.mgh using these two commands:
mri_segstats --i gamma.mgh --seg mc-z.th1.3.neg.sig.ocn.mgh --excludeid 0 --sum mc-z.th1.3.neg.sig.ocn.gamma.segstats
mri_segstats --i gammavar.mgh --seg mc-z.th1.3.neg.sig.ocn.mgh --excludeid 0 --sum mc-z.th1.3.neg.sig.ocn.gammavar.segstats
Next, (for each cluster, within each segstats summary file) I would take the “mean” from gamma, and the “mean” from gammavar, and calculate the positive 95% CI thus: gamma + 1.96*sqrt(gammavar) gamma - 1.96*sqrt(gammavar)
Would these two values would give me the 95% confidence interval for the effect of age on that cluster, in mm/year?
Thanks, -Kayle