Methodological quality was critically low in 9/10 systematic reviews in advanced cancer patients-A methodological

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Waldemar Siemens1, Guido Schwarzer2, Miriam S Rohe1

  • 1Clinic for Palliative Care, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.

Journal of Clinical Epidemiology
|March 20, 2021
PubMed
Abstract

Insights

Most systematic reviews (SRs) assessing advanced cancer treatments have critically low methodological quality, often due to non-registration and poor reporting. Addressing these issues in training can improve future SR quality.

Area of Science:

  • Medical Research Methodology
  • Evidence Synthesis
  • Oncology Research

Background:

  • Systematic reviews (SRs) are crucial for synthesizing evidence, especially in advanced cancer.
  • Assessing the methodological quality and heterogeneity considerations in SRs is vital for reliable conclusions.
  • Previous evaluations highlight variability in SR quality, necessitating a focused assessment.

Purpose of the Study:

  • To evaluate the methodological rigor of SRs focusing on advanced cancer interventions.
  • To determine the extent to which heterogeneity (clinical and methodological) is addressed in these SRs.
  • To identify common quality deficits in SRs to inform future improvements.

Main Methods:

  • A methodological study was conducted, searching three databases (Jan 2010-July 2019).
  • Included were interventional SRs with significant meta-analyses of at least four RCTs in advanced cancer.
  • The A MeaSurement Tool to Assess Systematic Reviews (AMSTAR) 2 was used for quality assessment.

Main Results:

  • Of 261 included SRs, 88.1% were critically low quality, primarily due to non-registration and inadequate reporting of excluded studies.
  • Heterogeneity was not explored in 19.5% of SRs.
  • Clinical heterogeneity was considered in 44.8%, methodological in 5.0%, and both in 30.7%.

Conclusions:

  • The methodological quality of SRs in advanced cancer is predominantly critically low.
  • Significant deficits exist in SR registration and reporting practices.
  • Improved training for review authors and peer reviewers on quality criteria is recommended to enhance future SRs.
Keywords:
AMSTAR 2HeterogeneityMeta-analysisMethodological qualityNeoplasmsSystematic review

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