Evidence map›Paper›PMID 34921318›Full record

ArticleNutrition reviews2022

Are systematic reviews addressing nutrition for cancer prevention trustworthy? A systematic survey of quality and risk of bias.

Joanna F Zajac, Dawid Storman, Mateusz J Swierz, Magdalena Koperny, Paulina Weglarz, Wojciech Staskiewicz, Magdalena Gorecka, Anna Skuza, Adam Wach, Klaudia Kaluzinska and 3 more

Open access · bronzeAbstract read
In one paragraph

Article in Nutrition reviews, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 6 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
6citing papers in PubMed, 1 pooled it
0.4field-weighted citation impact, top 23% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

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.

2 · The registry

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.

3 · Its place in the literature

Who cites it

6 citing papers in PubMed, 1 synthesis or guideline pooled it, 7 citations in OpenAlex.

  1. Pooled it
  2. Article
  3. Article
  4. Article
  5. Article
  6. Predictors of Higher Quality of Systematic Reviews Addressing Nutrition and Cancer Prevention.International journal of environmental research and public health · 2022
    Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

13 authors at 2 institutions in 3 countries.

Joanna F ZajacChair of Epidemiology and Preventive Medicine, Department of Hygiene and Dietetics, Jagiellonian University Medical College, Krakow, Poland.
Dawid StormanChair of Epidemiology and Preventive Medicine, Department of Hygiene and Dietetics, Jagiellonian University Medical College, Krakow, Poland.ORCID 0000-0001-6643-1389
Mateusz J SwierzChair of Epidemiology and Preventive Medicine, Department of Hygiene and Dietetics, Jagiellonian University Medical College, Krakow, Poland.
Magdalena KopernyChair of Epidemiology and Preventive Medicine, Department of Epidemiology, Jagiellonian University Medical College, Krakow, Poland.
Paulina WeglarzChair of Epidemiology and Preventive Medicine, Department of Hygiene and Dietetics, Jagiellonian University Medical College, Krakow, Poland.
Wojciech StaskiewiczStudents' Scientific Group of Systematic Reviews, Jagiellonian University Medical College, Krakow, Poland.
Magdalena GoreckaStudents' Scientific Group of Systematic Reviews, Jagiellonian University Medical College, Krakow, Poland.
Anna SkuzaStudents' Scientific Group of Systematic Reviews, Jagiellonian University Medical College, Krakow, Poland.
Adam WachStudents' Scientific Group of Systematic Reviews, Jagiellonian University Medical College, Krakow, Poland.
Klaudia KaluzinskaStudents' Scientific Group of Systematic Reviews, Jagiellonian University Medical College, Krakow, Poland.
Justyna Bochenek-CiborDepartment of Radiation Oncology, St Lukas Hospital, Tarnów, Poland.
Bradley C JohnstonDepartment of Nutrition and the Department of Epidemiology and Biostatistics, Texas A&M University, College Station, Texas, USA.
Malgorzata M BalaChair of Epidemiology and Preventive Medicine, Department of Hygiene and Dietetics, Jagiellonian University Medical College, Krakow, Poland.ORCID 0000-0003-1978-7264
Jagiellonian University · PLImpact · CA

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

contextThe last 30 years have yielded a vast number of systematic reviews and/or meta-analyses addressing the link between nutrition and cancer risk.

objectiveThe aim of this survey was to assess overall quality and potential for risk of bias in systematic reviews and meta-analyses (SRMAs) that examined the role of nutrition in cancer prevention. DATA SOURCES: MEDLINE, Embase, and the Cochrane Library databases were searched (last search performed November 2018). STUDY SELECTION: Studies identified as SRMAs that investigated a nutritional or dietary intervention or exposure for cancer prevention in the general population or in people at risk of cancer and in which primary studies had a comparison group were eligible for inclusion. Screening, data extraction, and quality assessment were conducted independently by 2 reviewers. DATA EXTRACTION: Altogether, 101 studies were randomly selected for analysis. The methodological quality and risk of bias were evaluated using the AMSTAR-2 and ROBIS tools, respectively.

resultsMost SRMAs included observational studies. Less than 10% of SRMAs reported a study protocol, and only 51% of SRMAs assessed the risk of bias in primary studies. Most studies conducted subgroup analyses, but only a few reported tests of interaction or specified subgroups of interest a priori. Overall, according to AMSTAR-2, only 1% of SRMAs were of high quality, while 97% were of critically low quality. Only 3% had a low risk of bias, according to ROBIS.

conclusionsThis systematic survey revealed substantial limitations with respect to quality and risk of bias of SRMAs. SRMAs examining nutrition and cancer prevention cannot be considered trustworthy, and results should be interpreted with caution. Peer reviewers as well as users of SRMAs should be advised to use the AMSTAR-2 and/or ROBIS instruments to help to determine the overall quality and risk of bias of SRMAs. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration number CRD42019121116.

Indexed as

Delivery of Health CareNeoplasmsBiasHumansSystematic Reviews as Topiccancernutritionpreventionqualityrisk of bias

Identifiers

PMID34921318
PMCPMC9086792
OpenAlexW4200240932

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

None linked

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.