“Spin” in wound care research: the reporting and interpretation of randomized controlled trials with statistically non-significant primary outcome results or unspecified primary outcomes

Abstract

BackgroundSpin in the reporting of randomized controlled trials, where authors report research in a way that potentially misrepresents results and mislead readers, has been demonstrated in the broader medical literature. We investigated spin in wound care trials with (a) no statistically significant result for the primary outcome and (b) no clearly specified primary outcome.MethodsWe searched the Cochrane Wounds Group Specialised Register of Trials for randomized controlled trials (RCTs). Eligible studies were: Parallel-group RCTs of interventions for foot, leg or pressure ulcers published in 2004 to 2009 (inclusive) with either a clearly identified primary outcome for which there was a statistically non-significant result (Cohort A) or studies that had no clear primary outcome (Cohort B).We extracted general study details. For both Cohorts A and B we then assessed for the presence of spin. For Cohort A we used a pre-defined process to assess reports for spin. For Cohort B we aimed to assess spin by recording the number of positive treatment effect claims made. We also compared the number of statistically significant and non-significant results reported in the main text and the abstract looking specifically for spin in the form of selective outcome reporting.ResultsOf the 71 eligible studies, 28 were eligible for Cohort A; of these, 71% (20/28) contained spin. Cohort B contained 43 studies; of these, 86% (37/43) had abstracts that claimed a favorable treatment claim. Whilst 74% (32/43) of main text results in Cohort B included at least one statistically non-significant result, this was not reflected in the abstract where only 28% contained (12/43) at least one statistically non-significant result.ConclusionsSpin is a frequent phenomenon in reports of RCTs of wound treatments. Studies without statistically significant results for the primary outcome used spin in 71% of cases. Furthermore, 33% (43/132) of reports of wound RCTs did not specify a primary outcome and there was evidence of spin and selective outcome reporting in the abstracts of these. Readers should be wary of only reading the abstracts of reports of RCTs of wound treatments since they are frequently misleading regarding treatment effects.

Wounds research for patient benefit: a 5-year programme of research

“…presenting outcomes for which there were statistically significant differences). In a related study, Lockyer et al 164 found that 86% of wound trials that did not define a primary outcome claimed a significant treatment effect. This raises deep suspicion of bias given the inadequate statistical power of trials in this field.…”

Industry sponsorship bias in clinical trials in implant dentistry: Systematic review and meta‐regression

“…There are several ways that industry sponsorship can influence clinical trials, from study design and conduction to selective reporting of results and spin in conclusions (Boutron, Dutton, Ravaud, & Altman, ; Boutron et al., ; Lockyer, Hodgson, Dumville, & Cullum, ; Schwendicke et al., ). Evidence demonstrates sponsorship bias in many medical studies, especially in the pharmaceutical field (Lexchin, ; Lexchin, Bero, Djulbegovic, & Clark, ).…”

Industry sponsorship in trials on fluoride varnish or gels for caries prevention

“…A large number of underlying mechanisms leading to such sponsorship bias have been identified, like specific trial design properties with regard to selection, performance, detection, attrition or reporting bias, the application of specific inclusion criteria, the statistical design and power, and the chosen comparators and controls . In addition to design and outcomes, reporting of findings might be affected by “spin,” that is a favourable interpretation and presentation of trial findings in the abstract or full text of a trial publication …”

“…6 In addition to design and outcomes, reporting of findings might be affected by "spin," that is a favourable interpretation and presentation of trial findings in the abstract or full text of a trial publication. [7][8][9] Many trials on fluoride varnishes or gels for caries prevention are funded by industry. While the general efficacy and effectiveness of fluoride on caries prevention has been demonstrated, 10,11 it is unclear to an extent of uncertainty whether any effects arising from the sponsored trials in respect of the nonsponsored trials are inflated, which in turn would affect the overall body of evidence.…”