Intended for healthcare professionals

Feature Christmas 2018: Look Before You Leap

Key opinion leaders’ guide to spinning a disappointing clinical trial result

BMJ 2018; 363 doi: https://doi.org/10.1136/bmj.k5207 (Published 13 December 2018) Cite this as: BMJ 2018;363:k5207

Re: Key opinion leaders’ guide to spinning a disappointing clinical trial result

Hartley and colleagues identified “negative” trials (which the reader presumes to mean trials which were statistically not significant); and accuses opinion leaders for “spinning” results when these findings are not interpreted as showing a treatment does not work.

The authors are misguided and wrong. Statistically non-significant findings rarely demonstrate that a treatment does not work; and most commonly represent uncertainty [Gerandter 20017]. The authors further seem to suggest that reports of non-significant findings should re-calculate required sample size. This is also incorrect, and is not necessary, as the information needed to interpret the trials findings is included in the confidence interval [Moher 2012].

[Gewandter 2017] Gewandter JS, McDermott MP, Kitt RA, Chaudari J, Koch JG, Evans SR, Gross RA, Markman JD, Turk DC, Dworkin RH. Interpretation of CIs in clinical trials with non-significant results: systematic review and recommendations. BMJ Open. 2017 Jul 18;7(7):e017288. doi: 10.1136/bmjopen-2017-017288. Review. PubMed PMID: 28720618; PubMed Central PMCID: PMC5726092.
[Moher 2012] Moher D, Hopewell S, Schulz KF, Montori V, Gøtzsche PC, Devereaux PJ, Elbourne D, Egger M, Altman DG; CONSORT. CONSORT 2010 explanation and elaboration: updated guidelines for reporting parallel group randomised trials. Int J Surg. 2012;10(1):28-55.

Competing interests: No competing interests

05 January 2019
Karla Hemming
Lecturer
University of Birmingham
Public Health Building, University of Birmingham