Evaluating Spin in the Abstracts of Systematic Reviews and Meta-Analyses on Cannabis Use Disorder

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Substance Abuse


Background: Clinicians rely upon abstracts to provide them quick synopses of research findings that may apply to their practice. Spin can exist within these abstracts that distorts or misrepresents the findings. Our goal was to evaluate the level of spin within systematic reviews (SRs) focused on the treatment of cannabis use disorder (CUD).

Methods: A systematic search was conducted in May 2020. To meet inclusion criteria, publications had to be either an SR or meta-analysis related to the treatment of cannabis use. Screening and data extraction was performed in a duplicate and masked fashion. Study quality was assessed using AMSTAR-2 .

Results: 16/24 SRs (66.7%) contained at least one form of spin in the abstract. The most common forms of spin identified were type 3-selective reporting of or overemphasis on efficacy outcomes or analysis favoring the beneficial effect of the experimental intervention (45.8%)-and type 8-the review's findings from a surrogate marker or a specific outcome to the global improvement of the disease (37.5%). No significant association between spin and intervention type, PRISMA requirements, or funding source was identified. Weak positive correlations were found between the presence of spin and abstract word count (r =.217) and between spin and AMSTAR-2 rating (r = 0.143). "Moderate" was the most common AMSTAR-2 rating (9/24, 37.5%), followed by "low" (7/24, 29.2%) and "critically low" (7/24, 29.2%). One systematic review received an AMSTAR-2 rating of "high" (1/24, 4.2%).

Conclusions: Spin was common among abstracts from the SRs focused on the treatments for CUD. Higher quality studies may help reduce the overall rate as well as standardizing treatment outcomes. To facilitate this, we encourage all authors, peer-reviewers, and editors to be more aware of the various types of spin as they can help reduce the overall amount of spin seen within the literature.



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CUD, Cannabis, spin, substance abuse, systematic review