Interim Analysis¶
Demets, D. L., & Lan, K. K. G. (1994). Interim Analysis: The Alpha Spending Function Approach. Statistics in Medicine, 13(13), 1341-1352.
Cited by¶
1 citation across 1 artifact.
Each citation links to the sentence it supports in the citing article.
Primes¶
- Termination Condition
- The prime's "optional stopping inflates false positives" inference is the entire reason the boundaries are computed from a pre-registered spending function rather than chosen on the fly: a stopping rule allowed to look and decide when to stop violates the fixed-design false-positive guarantee, so the post-halt certification ("the effect is real at level \(\alpha\)") is only valid if the predicate was fixed in advance.
This sourceIntroduces the alpha-spending-function method for pre-specifying group-sequential boundaries that preserve the overall Type I error.
Supported in partVerified against the publisher's abstract
The abstract states the alpha-spending function controls Type I error and permits flexible interim timing, but not that post-halt certification is valid only if the predicate was fixed in advance.
“Repeatedly testing interim data can inflate false positive error rates if not handled appropriately. Group sequential methods are a commonly used frequentist approach to control this error rate. Motivated by experience of clinical trials, the alpha spending function is one way to implement group sequential boundaries that control the type I error rate while allowing flexibility in how many interim analyses are to be …”
- The prime's "optional stopping inflates false positives" inference is the entire reason the boundaries are computed from a pre-registered spending function rather than chosen on the fly: a stopping rule allowed to look and decide when to stop violates the fixed-design false-positive guarantee, so the post-halt certification ("the effect is real at level \(\alpha\)") is only valid if the predicate was fixed in advance.
Verification¶
Does it exist? Confirmed. This work's DOI resolves to a registered record, which fixes its identity. That is all it fixes.
Does it back the claim? Read against the text for 1 of 1 citation: 1 supported in part. Each verdict is shown under its citation below, with what in the work backs the sentence.
Support is checked per citation rather than per work — the same source can be cited soundly in one article and wrongly in another. Per-citation recording began recently, so a citation with no recorded check is a gap in the record rather than evidence it went unchecked.
See how references were verified.
Registry ID ref:4ebdb5430386 · see in the full table