The DOI matches its Crossref record; 2 of the 2 references it cites were found in a registry or an index.
Group sequential procedures: Calendar versus information time
Abstract
This paper describes the relationship between information time and calendar time in the use of group sequential procedures to monitor interim analyses of clinical trials. Information time is the proportion of maximum subjects or events already observed. Interim analyses often occur at specified calendar times while the definition of classic group sequential procedures occurs in terms of information time. We extend the general group sequential approach of Lan and DeMets 1 to include this situation as well.
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Citations
Cites
Discrete sequential boundaries for clinical trials
GORDON LAN, K. K., & DEMETS, D. L. (1983) · Biometrika · doi:10.1093/biomet/70.3.659 · Cited by 2,310
Self-citationGroup sequential methods in the design and analysis of clinical trials
POCOCK, S. J. (1977) · Biometrika · doi:10.1093/biomet/64.2.191 · Cited by 1,831
Cited by
Dormandy, J. A., Charbonnel, B., Eckland, D. J., Erdmann, E., Massi-Benedetti, M., Moules, I. K., Skene, A. M., Tan, M. H., Lefèbvre, P. J., Murray, G. D., et al. (2005) · The Lancet · doi:10.1016/s0140-6736(05)67528-9 · Cited by 4,129
Adaptive design methods in clinical trials–a review
Chow, S.-C., & Chang, M. (2008) · Orphanet Journal of Rare Diseases · doi:10.1186/1750-1172-3-11 · Cited by 482
“Various stopping boundaries based on different boundary functions for controlling an overall type I error rate are available in the literature (see, e.g., Lan and DeMets, 1987; Wang and Tsiatis, 1987; Rosenberger et al., 2001; Jennison and Turnbull, 2000, 2005; Chow and Chang, 2006).”
White, W. B., Bakris, G. L., Bergenstal, R. M., Cannon, C. P., Cushman, W. C., Fleck, P., Heller, S., Mehta, C., Nissen, S. E., Perez, A., et al. (2011) · American Heart Journal · doi:10.1016/j.ahj.2011.08.004 · Cited by 152
The alpha spending function approach to interim data analyses
DeMets, D. L., & Lan, G. (1995) · Cancer Treatment and Research · doi:10.1007/978-1-4615-2009-2_1 · Cited by 58
Self-citation
Metadata
- Authors
- Lan, K. K. G., & Demets, D. L.
- Venue
- Statistics in Medicine
- Publisher
- Wiley
- Published
- 1989-10
- Volume
- 8
- Issue
- 10
- Pages
- 1191-1198
- ISSN
- 0277-6715 (ISSN-L)
- 1097-0258
- OpenAlex
- W2055502243
- Cited by
- 168
- References
- 2
- FWCI
- 3.68
- Type
- journal article
- Language
- en
- Open access
- closed
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- CoChat. (2026). Citation check: Group sequential procedures: Calendar versus information time. https://app.cochat.ai/papers/10.1002/sim.4780081003
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- Lan, K. K. G., & Demets, D. L. (1989). Group sequential procedures: Calendar versus information time. Statistics in Medicine. https://doi.org/10.1002/sim.4780081003
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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.
