RESUMO
OBJECTIVE: Spin is characterized as a misinterpretation of results that, whether deliberate or unintentional, culminates in misleading conclusions and steers readers toward an excessively optimistic perspective of the data. The primary objective of this systematic review was to estimate the prevalence and nature of spin within the traumatic brain injury (TBI) literature. Additionally, the identification of associated factors is intended to provide guidance for future research practices. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations were followed. A search of the MEDLINE/PubMed database was conducted to identify English-language articles published between January 1960 and July 2020. Inclusion criteria encompassed randomized controlled trials (RCTs) that exclusively enrolled TBI patients, investigating various interventions, whether surgical or nonsurgical, and that were published in high-impact journals. Spin was defined as 1) a focus on statistically significant results not based on the primary outcome; 2) interpreting statistically nonsignificant results for a superiority analysis of the primary outcome; 3) claiming or emphasizing the beneficial effect of the treatment despite statistically nonsignificant results; 4) conclusion focused in the per-protocol or as-treated analysis instead of the intention-to-treat (ITT) results; 5) incorrect statistical analysis; or 6) republication of a significant secondary analysis without proper acknowledgment of the primary outcome analysis result. Primary outcomes were those explicitly reported as such in the published article. Studies without a clear primary outcome were excluded. The study characteristics were described using traditional descriptive statistics and an exploratory inferential analysis was performed to identify those associated with spin. The studies' risk of bias was evaluated by the Cochrane Risk of Bias Tool. RESULTS: A total of 150 RCTs were included and 22% (n = 33) had spin, most commonly spin types 1 and 3. The overall risk of bias (p < 0.001), a neurosurgery department member as the first author (p = 0.009), absence of a statistician among authors (p = 0.042), and smaller sample sizes (p = 0.033) were associated with spin. CONCLUSIONS: The prevalence of spin in the TBI literature is high, even at leading medical journals. Studies with higher risks of bias are more frequently associated with spin. Critical interpretation of results and authors' conclusions is advisable regardless of the study design and published journal.
RESUMO
BACKGROUND AND OBJECTIVES: High-grade gliomas (HGGs) are aggressive tumors of the central nervous system that cause significant morbidity and mortality. Despite advances in surgery and radiation therapy (RT), HGG still has a high incidence of recurrence and treatment failure. Intraoperative radiotherapy (IORT) has emerged as a promising therapeutic approach to achieve local tumor control while sparing normal brain tissue from radiation-induced damage. METHODS: A systematic review and meta-analysis were conducted following PRISMA guidelines to evaluate the use of IORT for HGG. Eligible studies were included based on specific criteria, and data were independently extracted. Outcomes of interest included complications, IORT failure, survival rates at 12 and 24 months, and mortality. RESULTS: Sixteen studies comprising 436 patients were included. The overall complication rate after IORT was 17%, with significant heterogeneity observed. The IORT failure rate was 77%, while the survival rates at 12 and 24 months were 74% and 24%, respectively. The mortality rate was 62%. CONCLUSION: This meta-analysis suggests that IORT may be a promising adjuvant treatment for selected patients with HGG. Despite the high rate of complications and treatment failures, the survival outcomes were comparable or even superior to conventional methods. However, the limitations of the study, such as the lack of a control group and small sample sizes, warrant further investigation through prospective randomized controlled trials to better understand the specific patient populations that may benefit most from IORT. However, the limitations of the study, such as the lack of a control group and small sample sizes, warrant further investigation. Notably, the ongoing RP3 trial (NCT02685605) is currently underway, with the aim of providing a more comprehensive understanding of IORT. Moreover, future research should focus on managing complications associated with IORT to improve its safety and efficacy in treating HGG.
