SynthesisAnnals of surgical oncology2018
Induced Bias Due to Crossover Within Randomized Controlled Trials in Surgical Oncology: A Meta-regression Analysis of Minimally Invasive versus Open Surgery for the Treatment of Gastrointestinal Cancer.
Synthesis in Annals of surgical oncology, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 papers, 1 of them a synthesis that pooled it.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
9 citing papers in PubMed, 1 synthesis or guideline pooled it, 19 citations in OpenAlex.
- Prevalence and Impact of Treatment Crossover in Cardiac Surgery Randomized Trials: A Meta-Epidemiologic Study.Journal of the American Heart Association · 2019Pooled it
- Reducing unmeasured confounding from non-compliance with randomization in surgical RCTs: a simulation study.BMC medical research methodology · 2026Article
- Novel Strategies for Managing Retropharyngeal Lymph Node Metastases in Head and Neck and Thyroid Cancer with Transoral Robotic Surgery (TORS).Annals of surgical oncology · 2022Review
- Shared decision making in surgery: A scoping review of the literature.Health expectations : an international journal of public participation in health care and health policy · 2020Article
- Symptomatic adult spinal deformity: implications for treatment and research.Annals of translational medicine · 2020Article
- Oncological Minimally Invasive Surgery.Journal of oncology · 2019Article
- ASO Author Reflections: Induced Bias Due to Crossover Within Randomized Controlled Trials in Surgical Oncology.Annals of surgical oncology · 2018Article
- Analyses of repeated failures in cancer therapy for solid tumors: poor tumor-selective drug delivery, low therapeutic efficacy and unsustainable costs.Clinical and translational medicine · 2018Article
- Subscapularis-sparing approaches in shoulder arthroplasty: A systematic review.Journal of orthopaedicsArticle
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
10 authors at 4 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundRandomized controlled trials (RCTs) inform clinical practice and have provided the evidence base for introducing minimally invasive surgery (MIS) in surgical oncology. Crossover (unplanned intraoperative conversion of MIS to open surgery) may affect clinical outcomes and the effect size generated from RCTs with homogenization of randomized groups.
objectivesOur aims were to identify modifiable factors associated with crossover and assess the impact of crossover on clinical endpoints.
methodsA systematic review was performed to identify all RCTs comparing MIS with open surgery for gastrointestinal cancer (1990-2017). Meta-regression analysis was performed to analyze factors associated with crossover and the influence of crossover on endpoints, including 30-day mortality, anastomotic leak rate, and early complications.
resultsForty RCTs were included, reporting on 11,625 patients from 320 centers. Crossover was shown to affect one in eight patients (mean 12.6%, range 0-45%) and increased with American Society of Anesthesiologists score (β = + 0.895; p = 0.050). Pretrial surgeon volume (β = - 2.344; p = 0.037), composite RCT quality score (β = - 7.594; p = 0.014), and site of tumor (β = - 12.031; p = 0.021, favoring lower over upper gastrointestinal tumors) showed an inverse relationship with crossover. Importantly, multivariate weighted linear regression revealed a statistically significant positive correlation between crossover and 30-day mortality (β = + 0.125; p = 0.033), anastomotic leak rate (β = + 0.550; p = 0.004), and early complications (β = + 1.255; p = 0.001), based on intention-to-treat analysis.
conclusionsCrossover in trials was associated with an increase in 30-day mortality, anastomotic leak rate, and early complications within the MIS group based on intention-to-treat analysis, although our analysis did not assess causation. Credentialing surgeons by procedural volume and excluding high comorbidity patients from initial trials are important in minimizing crossover and optimizing RCT validity.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.