Year: 2018
Type: article
Abstract: We searched Medline for all English-language RCTs examining drug efficacy published in 2013. Our search identified 2851 potential studies. After screening titles and abstracts, 1101 potential studies remained. We randomly selected 646 of this sample, of which 190 studies were focused on drug efficacy and met inclusion criteria. For each study, we extracted information on outcome, funding source, financial ties to the manufacturer, and design characteristics (Table 1 ). The methods are described in full in a prior publication. 3 Trained abstractors used the results section of each study to determine whether the study reported positive or negative primary efficacy outcome. For superiority studies, if the drug of interest was statistically superior to the control (e.g., p -value < 0.05), the study outcome was defined as positive. For non-inferiority studies, if the drug of interest and the control had no significant difference, the study outcome was defined as positive. Study outcomes were assessed independently and in duplicate. Any disagreement on study outcome was resolved by discussion among the research team. The main outcome variable considered was the presence or absence of spin in the abstract of the RCT. We considered spin present if the abstract outcome was positive or mixed and the study reported a negative primary efficacy outcome in the results section of the manuscript. 1 Two clinician reviewers (SK, DK) evaluated all abstract conclusion sections, rating each conclusion as positive (in favor of study drug), negative (neutral or in favor of control), or mixed. A mixed rating meant that it was unclear in the abstract whether the study drug or the control was favored (i.e., if a subgroup analysis was emphasized over the primary outcome). The two clinicians remained blinded to the study outcome during this discussion. We report the prevalence of spin in a sample of RCTs. We examined the association between spin and study characteristics using a two-sided, 0.05-level χ test of significance. Statistical analysis was performed using SAS version 9 statistical software (SAS Institute Inc., Cary, NC). Of the 190 RCTs identified, 59 had a negative primary outcome in the results. These 59 studies were evaluated for the presence of spin. Among the 59 studies, clinician reviewers rated 8 abstracts as having a positive outcome and 17 as having a mixed outcome, for a total of 25 (42%) abstracts with spin. Study characteristics were largely similar across studies with and without spin (Table 1 ). Overall, studies with spin had smaller samples (median: 201) than studies without spin (median: 352; p = 0.03). There was no relationship between any financial tie to the manufacturer and presence of spin in the abstract ( p = 0.83).
Language: English
Subfield: Pharmacology
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $5,290
OpenAlex ID: W2783512958