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Assessing imprecision in Cochrane systematic reviews : A comparison of GRADE and Trial Sequential Analysis

Castellini, Greta ; Bruschettini, Matteo LU orcid ; Gianola, Silvia ; Gluud, Christian and Moja, Lorenzo (2018) In Systematic Reviews 7(1).
Abstract

Background: The evaluation of imprecision is a key dimension of the grading of the confidence in the estimate. Grading of Recommendations Assessment, Development and Evaluation (GRADE) gives recommendations on how to downgrade evidence for imprecision, but authors vary in their use. Trial Sequential Analysis (TSA) has been advocated for a more reliable assessment of imprecision. We aimed to evaluate reporting of and adherence to GRADE and to compare the assessment of imprecision of intervention effects assessed by GRADE and TSA in Cochrane systematic reviews. Methods: In this cross-sectional study, we included 100 Cochrane reviews irrespective of type of intervention with a key dichotomous outcome meta-analyzed and assessed by GRADE.... (More)

Background: The evaluation of imprecision is a key dimension of the grading of the confidence in the estimate. Grading of Recommendations Assessment, Development and Evaluation (GRADE) gives recommendations on how to downgrade evidence for imprecision, but authors vary in their use. Trial Sequential Analysis (TSA) has been advocated for a more reliable assessment of imprecision. We aimed to evaluate reporting of and adherence to GRADE and to compare the assessment of imprecision of intervention effects assessed by GRADE and TSA in Cochrane systematic reviews. Methods: In this cross-sectional study, we included 100 Cochrane reviews irrespective of type of intervention with a key dichotomous outcome meta-analyzed and assessed by GRADE. The methods and results sections of each review were assessed for adequacy of imprecision evaluation. We re-analyzed imprecision following the GRADE Handbook and the TSA Manual. Results: Overall, only 13.0% of reviews stated the criteria they applied to assess imprecision. The most common dimensions were the 95% width of the confidence intervals and the optimal information size. Review authors downgraded 48.0% of key outcomes due to imprecision. When imprecision was re-analyzed following the GRADE Handbook, 64% of outcomes were downgraded. Agreement between review authors' assessment and assessment by the authors of this study was moderate (kappa 0.43, 95% confidence interval [CI] 0.23 to 0.58). TSA downgraded 69.0% outcomes due to imprecision. Agreement between review authors' GRADE assessment and TSA, irrespective of downgrading levels, was moderate (kappa 0.43, 95% CI 0.21 to 0.57). Agreement between our GRADE assessment following the Handbook and TSA was substantial (kappa 0.66, 95% CI 0.49 to 0.79). Conclusions: In a sample of Cochrane reviews, methods for assessing imprecision were rarely reported. GRADE according to Handbook guidelines and TSA led to more severe judgment of imprecision rather than GRADE adopted by reviews' authors. Cochrane initiatives to improve adherence to GRADE Handbook are warranted. TSA may transparently assist in such development.

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author
; ; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Bias, Confidence intervals, Epidemiologic methods, Meta-analysis, Review
in
Systematic Reviews
volume
7
issue
1
article number
110
publisher
BioMed Central (BMC)
external identifiers
  • pmid:30055658
  • scopus:85050651996
ISSN
2046-4053
DOI
10.1186/s13643-018-0770-1
language
English
LU publication?
yes
id
23ef4da8-b5d1-4146-80bb-ccdc670b1eab
date added to LUP
2018-08-16 16:19:39
date last changed
2024-06-25 20:33:56
@article{23ef4da8-b5d1-4146-80bb-ccdc670b1eab,
  abstract     = {{<p>Background: The evaluation of imprecision is a key dimension of the grading of the confidence in the estimate. Grading of Recommendations Assessment, Development and Evaluation (GRADE) gives recommendations on how to downgrade evidence for imprecision, but authors vary in their use. Trial Sequential Analysis (TSA) has been advocated for a more reliable assessment of imprecision. We aimed to evaluate reporting of and adherence to GRADE and to compare the assessment of imprecision of intervention effects assessed by GRADE and TSA in Cochrane systematic reviews. Methods: In this cross-sectional study, we included 100 Cochrane reviews irrespective of type of intervention with a key dichotomous outcome meta-analyzed and assessed by GRADE. The methods and results sections of each review were assessed for adequacy of imprecision evaluation. We re-analyzed imprecision following the GRADE Handbook and the TSA Manual. Results: Overall, only 13.0% of reviews stated the criteria they applied to assess imprecision. The most common dimensions were the 95% width of the confidence intervals and the optimal information size. Review authors downgraded 48.0% of key outcomes due to imprecision. When imprecision was re-analyzed following the GRADE Handbook, 64% of outcomes were downgraded. Agreement between review authors' assessment and assessment by the authors of this study was moderate (kappa 0.43, 95% confidence interval [CI] 0.23 to 0.58). TSA downgraded 69.0% outcomes due to imprecision. Agreement between review authors' GRADE assessment and TSA, irrespective of downgrading levels, was moderate (kappa 0.43, 95% CI 0.21 to 0.57). Agreement between our GRADE assessment following the Handbook and TSA was substantial (kappa 0.66, 95% CI 0.49 to 0.79). Conclusions: In a sample of Cochrane reviews, methods for assessing imprecision were rarely reported. GRADE according to Handbook guidelines and TSA led to more severe judgment of imprecision rather than GRADE adopted by reviews' authors. Cochrane initiatives to improve adherence to GRADE Handbook are warranted. TSA may transparently assist in such development.</p>}},
  author       = {{Castellini, Greta and Bruschettini, Matteo and Gianola, Silvia and Gluud, Christian and Moja, Lorenzo}},
  issn         = {{2046-4053}},
  keywords     = {{Bias; Confidence intervals; Epidemiologic methods; Meta-analysis; Review}},
  language     = {{eng}},
  month        = {{07}},
  number       = {{1}},
  publisher    = {{BioMed Central (BMC)}},
  series       = {{Systematic Reviews}},
  title        = {{Assessing imprecision in Cochrane systematic reviews : A comparison of GRADE and Trial Sequential Analysis}},
  url          = {{http://dx.doi.org/10.1186/s13643-018-0770-1}},
  doi          = {{10.1186/s13643-018-0770-1}},
  volume       = {{7}},
  year         = {{2018}},
}