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Move over LOCF: principled methods for handling missing data in sleep disorder trials.

Publication ,  Journal Article
Olsen, MK; Stechuchak, KM; Edinger, JD; Ulmer, CS; Woolson, RF
Published in: Sleep Med
February 2012

Missing data, e.g. patient attrition, are endemic in sleep disorder clinical trials. Common approaches for dealing with this situation include complete-case analysis (CCA) and last observation carried forward (LOCF). Although these methods are simple to implement, they are deeply flawed in that they may introduce bias and underestimate uncertainty, leading to erroneous conclusions. There are alternative principled approaches, however, that are available in statistical software namely mixed-effects models and multiple imputation. In this paper we introduce terminology used to describe different assumptions about missing data. We emphasize that understanding reasons for missingness is a critical step in the analysis process. We describe and implement both linear mixed-effects models and an inclusive multiple imputation strategy for handling missing data in a randomized trial examining sleep outcomes. These principled strategies are compared with "complete-case analysis" and LOCF. These analyses illustrate that methodologies for accommodating missing data can produce different results in both direction and strength of treatment effects. Our goal is for this paper to serve as a guide to sleep disorder clinical trial researchers on how to utilize principled methods for incomplete data in their trial analyses.

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Published In

Sleep Med

DOI

EISSN

1878-5506

Publication Date

February 2012

Volume

13

Issue

2

Start / End Page

123 / 132

Location

Netherlands

Related Subject Headings

  • Sleep Wake Disorders
  • Research Design
  • Randomized Controlled Trials as Topic
  • Neurology & Neurosurgery
  • Models, Statistical
  • Longitudinal Studies
  • Humans
  • 5203 Clinical and health psychology
  • 3202 Clinical sciences
  • 1701 Psychology
 

Citation

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ICMJE
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Olsen, M. K., Stechuchak, K. M., Edinger, J. D., Ulmer, C. S., & Woolson, R. F. (2012). Move over LOCF: principled methods for handling missing data in sleep disorder trials. Sleep Med, 13(2), 123–132. https://doi.org/10.1016/j.sleep.2011.09.007
Olsen, Maren K., Karen M. Stechuchak, Jack D. Edinger, Christi S. Ulmer, and Robert F. Woolson. “Move over LOCF: principled methods for handling missing data in sleep disorder trials.Sleep Med 13, no. 2 (February 2012): 123–32. https://doi.org/10.1016/j.sleep.2011.09.007.
Olsen MK, Stechuchak KM, Edinger JD, Ulmer CS, Woolson RF. Move over LOCF: principled methods for handling missing data in sleep disorder trials. Sleep Med. 2012 Feb;13(2):123–32.
Olsen, Maren K., et al. “Move over LOCF: principled methods for handling missing data in sleep disorder trials.Sleep Med, vol. 13, no. 2, Feb. 2012, pp. 123–32. Pubmed, doi:10.1016/j.sleep.2011.09.007.
Olsen MK, Stechuchak KM, Edinger JD, Ulmer CS, Woolson RF. Move over LOCF: principled methods for handling missing data in sleep disorder trials. Sleep Med. 2012 Feb;13(2):123–132.
Journal cover image

Published In

Sleep Med

DOI

EISSN

1878-5506

Publication Date

February 2012

Volume

13

Issue

2

Start / End Page

123 / 132

Location

Netherlands

Related Subject Headings

  • Sleep Wake Disorders
  • Research Design
  • Randomized Controlled Trials as Topic
  • Neurology & Neurosurgery
  • Models, Statistical
  • Longitudinal Studies
  • Humans
  • 5203 Clinical and health psychology
  • 3202 Clinical sciences
  • 1701 Psychology