The DOI matches its Crossref record.
Sample-Size Formula for the Proportional-Hazards Regression Model
Abstract
A formula is derived for determining the number of observations necessary to test the equality of two survival distributions when concomitant information is incorporated. This formula should be useful in designing clinical trials with a heterogeneous patient population. Schoenfeld (1981, Biometrika 68, 316-319) derived the asymptotic power of a class of statistics used to test the equality of two survival distributions. That result is extended to the case where concomitant information is available for each individual and where the proportional-hazards model holds. The loss of efficiency caused by ignoring concomitant variables is also computed.
Overview
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Integrity signals
Registry
Cites
Statistics
Verification
Claims the paper makes
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
The self-check needs the paper’s full text.
Citations
Cited by
Relaxing the Rule of Ten Events per Variable in Logistic and Cox Regression
Vittinghoff, E., & McCulloch, C. E. (2007) · American Journal of Epidemiology · doi:10.1093/aje/kwk052 · Cited by 4,359
Keys, H. M., Bundy, B. N., Stehman, F. B., Muderspach, L. I., Chafe, W. E., Suggs, C. L., Walker, J. L., & Gersell, D. (1999) · New England Journal of Medicine · doi:10.1056/nejm199904153401503 · Cited by 1,923
Sedlis, A., Bundy, B. N., Rotman, M. Z., Lentz, S. S., Muderspach, L. I., & Zaino, R. J. (1999) · Gynecologic Oncology · doi:10.1006/gyno.1999.5387 · Cited by 1,315
An anti-CD3 antibody, teplizumab, in relatives at risk for type 1 diabetes
Herold, K. C., Bundy, B. N., Long, S. A., Bluestone, J. A., DiMeglio, L. A., Dufort, M. J., Gitelman, S. E., Gottlieb, P. A., Krischer, J. P., Linsley, P. S., et al. (2019) · New England Journal of Medicine · doi:10.1056/nejmoa1902226 · Cited by 1,189
Cognitive Therapy for the Prevention of Suicide Attempts: A Randomized Controlled Trial
Brown, G. K., Ten Have, T., Henriques, G. R., Xie, S. X., Hollander, J. E., & Beck, A. T. (2005) · JAMA · doi:10.1001/jama.294.5.563 · Cited by 1,045
Metadata
- Authors
- Schoenfeld, D. A.
- Venue
- Biometrics
- Publisher
- JSTOR
- Published
- 1983-06
- Volume
- 39
- Issue
- 2
- Pages
- 499
- ISSN
- 0006-341X (ISSN-L)
- OpenAlex
- W1988262403
- Cited by
- 1,096
- References
- 0
- FWCI
- 3.41
- Type
- journal article
- Language
- en
- Open access
- closed
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
How to cite
Cite CoChat for the checks on this page, and the paper for its own findings.
- This page
- CoChat. (2026). Citation check: Sample-Size Formula for the Proportional-Hazards Regression Model. https://app.cochat.ai/papers/10.2307/2531021
- The paper
- Schoenfeld, D. A. (1983). Sample-Size Formula for the Proportional-Hazards Regression Model. Biometrics. https://doi.org/10.2307/2531021
Data sources
Bibliographic data: Semantic Scholar, OpenAlex, Crossref.
Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).
Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.
