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Abstract

Outcome reporting bias occurs when outcomes in research studies are selectively reported, the selection being influenced by the study results. For benefit outcomes, we have shown how risk assessments using the Outcome Reporting Bias in Trials risk classification scale can be used to calculate bias-adjusted treatment effect estimates. This paper presents a new and simpler version of the benefits method, and shows how it can be extended to cover the partial reporting and non-reporting of harm outcomes. Our motivating example is a Cochrane systematic review of 12 studies of Topiramate add-on therapy for drug-resistant partial epilepsy. Bias adjustments for partially reported or unreported outcomes suggest that the review has overestimated the benefits and underestimated the harms of the test treatment.

Keywords

Outcome reporting bias meta analysis selective reporting Outcome Reporting Bias in Trials classification

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References

Alderson

Tan

. Use of Cochrane Reviews in NICE clinical guidelines [editorial]. Cochrane Database Syst Rev 2011; 12: ED000032–ED000032.

Hutton

Williamson

. Bias in meta-analysis due to outcome variable selection within studies. Appl Stat 2000; 49: 359–370.

Dwan

Gamble

Williamson

et al.

Systematic review of the empirical evidence of study publication bias and outcome reporting bias - An updated review. PLoS One 2013; 8: e66844–e66844.

Saini

Loke

Gamble

et al.

Selective reporting bias of harm outcomes within studies: findings from a cohort of systematic reviews. Br Med J 2014; 349: g6501–g6501.

Kirkham

Dwan

Dodd

et al.

The impact of outcome reporting bias in randomised controlled trials on a cohort of systematic reviews. Br Med J 2010; 340: c365–c365.

Copas

Dwan

Kirkham

et al.

A model-based correction for outcome reporting bias in meta-analysis. Biostatistics 2014; 15: 370–383.

Pulman

Jette

Dykeman

et al.

Topiramate add-on for drug-resistant partial epilepsy. Cochrane Database Syst Rev 2014, Issue 2. Art. No.: CD001417. DOI: 10.1002/14651858.CD001417.pub3.

Ben-Menachem E, Henriksen O, Dam M, et al. Double-blind, placebo-controlled trial of topiramate as add-on therapy in patients with refractory partial seizures. Epilepsia 1996; 37: 539–543.

Elterman RD, Glauser TA, Wyllie E, et al. A double-blind, randomized trial of topiramate as adjunctive therapy for partial-onset seizures in children. Neurology 1999; 52: 1338–1344.

10.

Faught E, Wilder BJ, Ramsay RE, et al. Topiramate placebo-controlled dose-ranging trial in refractory partial epilepsy using 200-, 400-, and 600-mg daily dosages. Neurology 1996; 46: 1684–1690.

11.

Guberman A, Neto W and Gassmann-Mayer C. EPAJ-119 Study Group. Low-dose topiramate in adults with treatment-resistant partial-onset seizures. Acta Neurologica Scandinavica 2002; 106: 183–189.

12.

Korean Topiramate Study Group. Topiramate in medically intractable partial epilepsies: double-blind placebo-controlled randomized parallel group trial. Epilepsia 1999; 40: 1767–1774.

13.

Privitera M, Fincham R, Pnery J, et al. Topiramate placebo-controlled dose-ranging trial in refractory partial epilepsy using 600-, 800-, and 1,000-mg daily dosages. Neurology 1996;46: 1678–1683.

14.

Rosenfeld W, Abou-Khalil B, Reife R, et al. Topiramate YF/YG Study Group. Placebo-controlled trial of topiramate as adjunctive therapy to carbamazepine or phenytoin for partial-onset seizures. Epilepsia 1996; 37(Suppl 5): 153.

15.

Sharief M, Viteri C, Ben-Menachem E, et al. Double-blind, placebo-controlled study of topiramate in patients with refractory partial epilepsy. Epilepsy Research 1996; 25: 217–224.

16.

Tassinari CA, Michelucci R, Chauvel P, et al. Double-blind, placebo-controlled trial of topiramate (600 mg daily) for the treatment of refractory partial epilepsy. Epilepsia 1996; 37: 763–768.

17.

Yen DJ, Yu HY, Guo YC, et al. A double-blind, placebo-controlled study of topiramate in adult patients with refractory partial epilepsy. Epilepsia 2000; 41: 1162–1166.

18.

Zhang L, Huang J, Zhuang JH, et al. Topiramate as an adjunctive treatment for refractory partial epilepsy in the elderly. Journal of International Medical Research 2011; 39: 408–415.

19.

Coles H, Baker G and O'Donoghue M. Seizure severity in patients with partial onset (POS) or primary generalised tonic-clonic (PGTC) seizures following treatment with topiramate. A comparison of two different methodologies in a randomised controlled trial. Epilepsia 1999; 40(Suppl 2): 285.

20.

Higgins JPT, Deeks JJ and Altman DG (eds). Chapter 16: Special topics in statistics. In: Higgins JPT and Green S (eds). Cochrane Handbook for Systematic Reviews of Interventions. Version 5.1.0 [updated March 2011]. The Cochrane Collaboration, 2011. Available from www.cochrane-handbook.org.

21.

Mantel

Haenszel

. Statistical aspects of the analysis of data from retrospective studies of disease. J Natl Cancer Inst 1959; 22: 719–748.

22.

Hardy

Thompson

. A likelihood approach to meta-analysis with random effects. Stat Med 1996; 15: 619–629.

23.

Williamson

Gamble

. Application and investigation of a bound for outcome reporting bias. Trials 2007; 8: 9

24.

Kirkham

Riley

Williamson

. A multivariate meta-analysis solution for reducing the impact of outcome reporting bias in systematic reviews. Stat Med 2012; 31: 2179–2195.

25.

Chan

Krleza-Jeric

Schmid

et al.

Outcome reporting bias in randomized trials funded by the Canadian Institutes of Health Research. Can Med J 2004; 171: 735–740.

26.

Little

RJA

Rubin

. Statistical analysis with missing data, 2nd ed. New York: Wiley, 2002.

27.

Rubin

. Inference and missing data. Biometrika 1976; 63: 581–592.

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Model-based sensitivity analysis for outcome reporting bias in the meta analysis of benefit and harm outcomes

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