{
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"uri": "at://did:plc:wwyqal4cnqhuwyacdj7rqq3n/app.bsky.feed.post/3mkatazfgvlb2"
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"path": "/t/sample-size-determination-confirmatory-prognostic-factor-study/28722#post_2",
"publishedAt": "2026-04-24T14:24:33.000Z",
"site": "https://discourse.datamethods.org",
"textContent": "Covariate adjustment, as long as the covariates have some impact on Y, always increases power. For nonlinear model it seems to decrease power but this is a mirage. The standard errors can increase with covariate adjustment in say logistic or Cox models, but the \\hat{\\beta} increase more than that.",
"title": "Sample size determination-confirmatory prognostic factor study"
}