The DOI matches its Crossref record; 18 of the 18 references it cites were found in a registry or an index.
Handling drop‐out in longitudinal clinical trials: a comparison of the LOCF and MMRM approaches
Open accessAbstract
This study compares two methods for handling missing data in longitudinal trials: one using the last‐observation‐carried‐forward (LOCF) method and one based on a multivariate or mixed model for repeated measurements (MMRM). Using data sets simulated to match six actual trials, I imposed several drop‐out mechanisms, and compared the methods in terms of bias in the treatment difference and power of the treatment comparison. With equal drop‐out in Active and Placebo arms, LOCF generally underestimated the treatment effect; but with unequal drop‐out, bias could be much larger and in either direction. In contrast, bias with the MMRM method was much smaller; and whereas MMRM rarely caused a difference in power of greater than 20%, LOCF caused a difference in power of greater than 20% in nearly half the simulations. Use of the LOCF method is therefore likely to misrepresent the results of a trial seriously, and so is not a good choice for primary analysis. In contrast, the MMRM method is unlikely to result in serious misinterpretation, unless the drop‐out mechanism is missing not at random (MNAR) and there is substantially unequal drop‐out. Moreover, MMRM is clearly more reliable and better grounded statistically. Neither method is capable of dealing on its own with trials involving MNAR drop‐out mechanisms, for which sensitivity analysis is needed using more complex methods. Copyright © 2007 John Wiley & Sons, Ltd.
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“Building on a likelihood-based approach, the linear mixed models analysis uses all available data and produces unbiased parameter estimates under the assumption of data being missing at random, making it suitable for intention-to-treat analyses in longitudinal studies with data missing at random [56-58].”
From Comparing internet-based cognitive behavioral therapy with standard care for women with fear of birth: Randomized controlled trial (2018) · cites this paper as [57]
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Cites
Statistical Analysis With Missing Data
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Roderick J.A. Little, Donald B. Rubin — Statistical Analysis with Missing Data
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Molenberghs, G. (2004) · Biostatistics · doi:10.1093/biostatistics/5.3.445 · Cited by 463
ACCOUNTING FOR DROPOUT BIAS USING MIXED-EFFECTS MODELS
Mallinckrodt, C. H., Clark, W. S., & David, S. R. (2001) · Journal of Biopharmaceutical Statistics · doi:10.1081/bip-100104194 · Cited by 398
Analyzing incomplete longitudinal clinical trial data
Molenberghs, G. (2004) · Biostatistics · doi:10.1093/biostatistics/kxh001 · Cited by 378
A multiple imputation strategy for clinical trials with truncation of patient data
Lavori, P. W., Dawson, R., & Shera, D. M. (1995) · Statistics in Medicine · doi:10.1002/sim.4780141707 · Cited by 291
Assessing and interpreting treatment effects in longitudinal clinical trials with missing data
Mallinckrodt, C. H., Sanger, T. M., Dubé, S., DeBrota, D. J., Molenberghs, G., Carroll, R. J., Potter, W. Z., & Tollefson, G. D. (2003) · Biological Psychiatry · doi:10.1016/s0006-3223(02)01867-x · Cited by 250
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Moher, D., Hopewell, S., Schulz, K. F., Montori, V., Gotzsche, P. C., Devereaux, P. J., Elbourne, D., Egger, M., & Altman, D. G. (2010) · BMJ · doi:10.1136/bmj.c869 · Cited by 8,883
Moher, D., Hopewell, S., Schulz, K. F., Montori, V., Gøtzsche, P. C., Devereaux, P. J., Elbourne, D., Egger, M., & Altman, D. G. (2012) · International Journal of Surgery · doi:10.1016/j.ijsu.2011.10.001 · Cited by 2,345
“Many authors have severely criticised last observation carried forward [229 e 231].”
BackgroundMoher, D., Hopewell, S., Schulz, K. F., Montori, V., Gøtzsche, P. C., Devereaux, P. J., Elbourne, D., Egger, M., & Altman, D. G. (2010) · Journal of Clinical Epidemiology · doi:10.1016/j.jclinepi.2010.03.004 · Cited by 1,858
Lock, J., Le Grange, D., Agras, W. S., Moye, A., Bryson, S. W., & Jo, B. (2010) · Archives of General Psychiatry · doi:10.1001/archgenpsychiatry.2010.128 · Cited by 866
Douillard, J. Y., Siena, S., Cassidy, J., Tabernero, J., Burkes, R., Barugel, M., Humblet, Y., Bodoky, G., Cunningham, D., Jassem, J., et al. (2014) · Annals of Oncology · doi:10.1093/annonc/mdu141 · Cited by 606
Metadata
- Authors
- Lane, P.
- Affiliations
- GlaxoSmithKline (United Kingdom) (GB)
- Corresponding author
- Lane, Peter
- ORCID
- Lane, Peter
- Venue
- Pharmaceutical Statistics
- Publisher
- Wiley
- Published
- 2007-03-09
- Volume
- 7
- Issue
- 2
- Pages
- 93-106
- ISSN
- 1539-1604 (ISSN-L)
- 1539-1612
- OpenAlex
- W2068456795
- Cited by
- 262
- References
- 17
- Citations by year
- 2026: 5 · 2025: 12 · 2024: 9 · 2023: 4 · 2022: 12 · 2021: 17 · 2020: 9 · 2019: 8 · 2018: 5 · 2017: 14 · 2016: 10 · 2015: 22 · 2014: 24 · 2013: 20 · 2012: 12
- FWCI
- 17.61
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Pharmaceutical Statistics (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods and Bayesian Inference
- Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Clinical Trials
- Physical Sciences › Mathematics › Statistics and Probability › Advanced Causal Inference Techniques
- Keywords
- dropout, missing data, last observation carried forward, bias in treatment effect estimation, statistical power, missing not at random, sensitivity analysis
- MeSH terms
- Clinical Trials as Topic, Computer Simulation, Data Interpretation, Statistical, Humans, Longitudinal Studies, Patient Dropouts, Bias, Multivariate Analysis
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