Single reviewer / lack of double checking

This problem is addressed in PRISMA 2009, PRISMA 2020, ROBIS and MECIR. It is only partically addressed in AMSTAR 2. Key stages of the systematic review process should be performed in duplicate to ensure reliabiity and consistency of decisions. This includes screening studies, data extraction and quality assessment. It is not enough to state that multiple people were involved. What is key is to understand what proportion of data were independently checked.

Articles that support this problem:

Assessing the methodological quality of systematic reviews in radiation oncology: A systematic review

2017 : Cancer epidemiology

Methodologic quality of systematic reviews published in the plastic and reconstructive surgery literature: a systematic review

2016 : Plastic and reconstructive surgery

Journal impact factor is associated with PRISMA endorsement, but not with the methodological quality of low back pain systematic reviews: a methodological review

2020 : European spine journal

A case study of binary outcome data extraction across three systematic reviews of hip arthroplasty: errors and differences of selection

2013 : Bmc research notes

An analysis of quality of systematic reviews on pharmacist health interventions

2012 : International journal of clinical pharmacy

The methodological quality of systematic reviews on the treatment of adult major depression needs improvement according to AMSTAR 2: A cross-sectional study

2020 : Heliyon

Methodological quality of systematic reviews published in the urological literature from 1998 to 2012

2015 : The journal of urology

An AMSTAR assessment of the methodological quality of systematic reviews of oral healthcare interventions published in the Journal of Applied Oral Science (JAOS)

2011 : Journal of applied oral science

Quality assessment of systematic reviews of health care interventions using AMSTAR

2011 : Indian pediatrics

Evaluation of methodology and quality characteristics of systematic reviews in orthodontics

2011 : Orthodontics & craniofacial research

Prostate Artery Embolisation: Poor Design and Reporting Impact the Value of Current Systematic Reviews

2018 : European urology

Quality assessment of systematic reviews regarding the effectiveness of zygomatic implants: an overview of systematic reviews

2020 : Medicina oral, patologia oral y cirugia bucal

Quality assessment of the methods used in published opioid conversion reviews

2012 : Journal of pain & palliative care pharmacotherapy

The currency, completeness and quality of systematic reviews of acute management of moderate to severe traumatic brain injury: A comprehensive evidence map

2018 : Plos one [electronic resource]

Systematic reviews and meta-analyses of home telemonitoring interventions for patients with chronic diseases: a critical assessment of their methodological quality

2013 : Journal of medical internet research

Quality assessment of systematic reviews on periodontal regeneration in humans

2013 : Journal of periodontology

The effectiveness of mandibular advancement devices in the treatment of obstructive sleep apnoea in adults: a methodological quality assessment of systematic reviews

2020 : European journal of orthodontics

Systematic Reviews in Craniofacial Trauma—Strengths and Weaknesses

2016 : Annals of plastic surgery

Single-reviewer abstract screening missed 13 percent of relevant studies: a crowd-based, randomized controlled trial

2020 : Journal of clinical epidemiology

The value of a second reviewer for study selection in systematic reviews

2019 : Research synthesis methods

Reporting and methodological quality of systematic reviews in the orthopaedic literature

2013 : Jbjs

The methodological quality of systematic reviews and meta-analyses on the effectiveness of non-pharmacological cancer pain management

2015 : Pain management nursing

Systematic reviews supporting practice guideline recommendations lack protection against bias

2013 : Journal of clinical epidemiology

Appraisal of systematic reviews on the management of peri-implant diseases with two methodological tools

2018 : Journal of clinical periodontology

Epidemiology, quality, and reporting characteristics of systematic reviews and meta-analyses of nursing interventions published in Chinese journals

2015 : Nursing outlook

Methodological and reporting quality evaluation of systematic reviews on acupuncture in women with polycystic ovarian syndrome: A systematic review

2018 : Complementary therapies in clinical practice

Methodological quality of systematic reviews in subfertility: a comparison of Cochrane and non-Cochrane systematic reviews in assisted reproductive technologies

2012 : Human reproduction

Systematic review adherence to methodological or reporting quality

2017 : Systematic reviews

Assessment of the quality of systematic reviews on COVID‐19: A comparative study of previous coronavirus outbreaks

2020 : Journal of medical virology

Epidemiology, quality and reporting characteristics of systematic reviews of traditional Chinese medicine interventions published in Chinese journals

2011 : Plos one

Poor reliability between Cochrane reviewers and blinded external reviewers when applying the Cochrane risk of bias tool in physical therapy trials

2014 : Plos one

Impact of choice of quality appraisal tool for systematic reviews in overviews

2014 : Journal of evidence-based medicine

Use of methodological tools for assessing the quality of studies in periodontology and implant dentistry: a systematic review

2014 : Journal of clinical periodontology

Identifying studies for systematic reviews of diagnostic tests was difficult due to the poor sensitivity and precision of methodologic filters and the lack of information in the abstract

2005 : Journal of clinical epidemiology

Error rates of human reviewers during abstract screening in systematic reviews

2020 : Plos one

The association between periodontitis and coronary heart disease: a quality assessment of systematic reviews

2013 : Journal of the american dental association

Quality assessment of systematic reviews on alveolar ridge preservation

2013 : Journal of the american dental association

Non-communicable diseases research output in the Eastern Mediterranean region: an overview of systematic reviews

2020 : Bmc medical research methodology

Methodological quality and descriptive characteristics of prosthodontic‐related systematic reviews

2013 : Journal of oral rehabilitation

The landscape of systematic reviews in urology (1998 to 2015): an assessment of methodological quality

2017 : Bju international

Data extraction methods: an analysis of internal reporting discrepancies in single manuscripts and practical advice

2020 : Journal of clinical epidemiology

Need for quality improvement in renal systematic reviews

2008 : Clinical journal of the american society of nephrology

Methodological quality of systematic reviews and clinical trials on women's health published in a Brazilian evidence-based health journal

2013 : Clinics

The quality of systematic reviews of health-related outcome measurement instruments

2016 : Quality of life research

Evaluation of the methodological quality of systematic reviews of health status measurement instruments

2009 : Quality of life research

The fate of urological systematic reviews registered in PROSPERO

2019 : World journal of urology

Low Methodological Quality of Systematic Reviews Published in the Urological Literature (2016-2018)

2020 : Urology

Epidemiology and Reporting Characteristics of Systematic Reviews of Biomedical Research: A Cross-Sectional Study

2016 : Plos medicine

Characteristics and quality of systematic reviews and meta-analyses of observational nutritional epidemiology: a cross-sectional study

2021 : American journal of clinical nutrition

Issues in reporting of systematic review methods in health app-focused reviews: A scoping review

2020 : Health informatics journal

Clinical performance of and patient satisfaction with conventional complete dentures with different occlusal schemes: A systematic review of systematic reviews

2022 : Journal of prosthetic dentistry

Methodological appraisal of the evidence about efficacy of metabolic surgery in adults with non-morbid obesity and hypertension: An overview of systematic reviews

2022 : International journal of surgery

Striving for Happily Ever After: Supportive Interventions for Youth Leaving Residential Placement. A Systematic Review of Reviews

2022 : Child & adolescent mental health

Many systematic reviews with a single author are indexed in PubMed

2023 : Journal of clinical epidemiology

Examining the state, quality and strength of the evidence in the research on built environments and physical activity among adults: An overview of reviews from high income countries

2022 : Health & place

Impact of industry sponsorship on the quality of systematic reviews of vaccines: a cross-sectional analysis of studies published from 2016 to 2019

2022 : Systematic reviews

Comment on "Ticks infected with Crimean-Congo hemorrhagic fever virus (CCHFV): A decision approach systematic review and meta-analysis regarding their role as vectors"

2023 : Travel medicine and infectious disease

An Overview of Systematic Reviews: Acupuncture in the Treatment of Essential Hypertension

2022 : International journal of general medicine