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Allocation concealment as a potentially useful aspect of randomised experiments

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Abstract

In experiments where subjects are allocated to different treatments, implementing allocation concealment simply means that procedures are used to prevent conscious or unconscious human bias influencing the allocation of particular subjects to particular treatments. It is a related, but distinct, procedure to blinding. Allocation concealment is a neglected, but potentially valuable, tool in improving the design of experiments, and it can always be applied inexpensively and easily to any experiment involving allocation of subjects between treatment groups. I feel allocation concealment should be adopted more widely.

Significance statement

Allocation concealment simply means that the allocation of particular subjects to particular treatment groups in an experiment is not known to anyone prior to subjects being allocated to particular groups. It is a related but distinct procedure to blinding. Allocation concealment is a neglected but valuable tool in avoiding the introduction of biases into an experiment; and it can always be applied cheaply and easily. BES is right to encourage greater consideration of blinding, but it should also encourage allocation concealment.

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References

  • Clark L, Schmidt U, Tharmanathan P, Adamson J, Hewitt C, Torgerson D (2013) Allocation concealment: a methodological review. J Eval Clin Pract 19:708–712

    Article  PubMed  Google Scholar 

  • Cook DJ, Teves L, Tymianski M (2012) Treatment of stroke with a PSD-95 inhibitor in the gyrencephalic primate brain. Nature 483:213–217

    Article  CAS  PubMed  Google Scholar 

  • Doig GS, Simpson F (2005) Randomization and allocation concealment: a practical guide for researchers. J Crit Care 20:187–191

    Article  PubMed  Google Scholar 

  • Holman L, Head ML, Lanfear R, Jennions MD (2015) Evidence of experimental bias in the life sciences: why we need blind data recording. PLoS Biol 13:e1002190

    Article  PubMed  PubMed Central  Google Scholar 

  • Jüni P, Altman DG, Egger M (2001) Assessing the quality of controlled clinical trials. Brit Med J 323:42–46

    Article  PubMed  PubMed Central  Google Scholar 

  • Kardish MR, Mueller UG, Amador-Vargas S, Dietrich EI, Ma R, Barrett B, Fang C-C (2015) Blind trust in unblinded observation in ecology, evolution, and behavior. Front Ecol Evol 3:51

    Article  Google Scholar 

  • Milinski M (1997) How to avoid seven deadly sins in the study of behavior. Adv Stud Behav 26:159–180

    Article  Google Scholar 

  • Moher D, Fortin P, Jadad AR, Jüni P, Klassen T, Le Lorier J, Liberati A, Linde K, Penna A (1996) Completeness of reporting of trials published in languages other than English: implications for conduct and reporting of systematic reviews. Lancet 347:363–366

    Article  CAS  PubMed  Google Scholar 

  • Schulz KF, Chalmers I, Hayes RJ, Altman DG (1995) Empirical evidence of bias: dimensions of methodological quality associated with estimates of treatment effects in controlled trials. JAMA 273:408–412

    Article  CAS  PubMed  Google Scholar 

  • Traniello JF, Bakker TCM (2015) Minimizing observer bias in behavioral research: blinded methods reporting requirements for Behavioral Ecology and Sociobiology. Behav Ecol Sociobiol 69:1573–1574

    Article  Google Scholar 

  • Tuyttens FAM, de Graaf S, Heerkens JLT, Jacobs L, Nalon E, Ott S, Stadig L, Van Laer E, Ampe B (2014) Observer bias in animal behaviour research: can we believe what we score, if we score what we believe? Anim Behav 90:273–280

    Article  Google Scholar 

  • van Wilgenburg E, Elgar MA (2013) Confirmation bias in studies of nestmate recognition: a cautionary note for research into the behaviour of animals. PLoS One 8:e53548

    Article  PubMed  PubMed Central  Google Scholar 

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Acknowledgements

I thank the editors and two referees for the helpful comments.

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Authors and Affiliations

  1. School of Biology, University of St Andrews, St Andrews, UK

    G. D. Ruxton

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  1. G. D. Ruxton
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Correspondence to G. D. Ruxton.

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Note on blinding

This paper did not involve data collection, so blind procedures could not be applied.

Ethical statement

This paper did not involve data collection and so no ethical issues arise. Similarly, the author considers that there are no conflicts of interest or funding issues that should be declared.

Additional information

Communicated by L. Z. Garamszegi

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Ruxton, G.D. Allocation concealment as a potentially useful aspect of randomised experiments. Behav Ecol Sociobiol 71, 31 (2017). https://doi.org/10.1007/s00265-016-2261-5

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  • DOI: https://doi.org/10.1007/s00265-016-2261-5

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