I am trying to compute the sample size of a cohort study, pregnant women beyond 20 weeks of gestation with normal blood pressure <130/80 mmhg versus pregnant women beyong 20 weeks of gestation with subclinical elevation of blood pressure 130 - 139/ 80 - 89 mmhg. The outcome of interest is onset (incidence) of pregancy induced hypetenstion as per existing threasholds 140/90 mmhg). Recent cohort study of 2,090 normotensive women, 1318 (63.0%) remained normotensive for their entire antenatal course prior to delivery admission and 772 (37.0%) had new-onset blood pressure elevations between 130-139/80-89 mmHg. The incidence of pregnancy induced hypertension in the normotensive group was 11.6% vs 32% in the blood pressure elevation group. https://www.ajog.org/article/S0002-9378(20)30635-9/pdf
Therefore using 0.116 as the proportion of the outcome in the normotensive group, i would like to calculate the sample size for a cohort study powered at 80%, with type I error of 5%.
will the power twoproportions function in STATA sufice? how would I incoperate loss to follow up (drop out) in the said syntax?
Related Posts with estimating sample size for cohort studies
Using macros with Drawnorm to "clone" multiple datasetsHi there I am trying to loop drawnorm over mutiple STATA datasets, however I want drawnorm to use t…
Looping in StataHi, I am facing an issue that I am trying for a while. I want to create a dummy variable taking val…
Oaxaca-Blinder decomposition: percentage greater than 100Dear all, I'm currently running the Oaxaca-Blinder Decomposition on a binary outcome variable, stun…
Estimate parameters from restrictions on regression parameters via GMMDear all, I am trying to replicate the market resiliency model used in the following paper: Bessemb…
How to compare the slope gradients after mixed commandDear Stata experts, I have a repeated measures study design where subjects were followed over 5 vis…
Subscribe to:
Post Comments (Atom)
0 Response to estimating sample size for cohort studies
Post a Comment