Gordon H. Guyatt

15 minute #JAMA podcast in which I interview world authority @thomasagoritsas.bsky.social on how to Use a Patient Management #Recommendations: #ClinicalPracticeGuidelines and #DecisionAnalyses

edhub.ama-assn.org/jn-learning/...

Potential impact on estimated treatment effects of information lost to follow-up in randomised controlled trials (LOST-IT): systematic review - PubMed Plausible assumptions regarding outcomes of patients lost to follow-up could change the interpretation of results of randomised controlled trials published in top medical journals.

This #BMJ article demonstrates that plausible assumptions regarding outcomes of patients lost to follow-up could often change the interpretation of results of #RandomisedControlledTrials published in top medical journals.

pubmed.ncbi.nlm.nih.gov/22611167/

Can we individualize the 'number needed to treat'? An empirical study of summary effect measures in meta-analyses - PubMed The fixed effects OR, random effects OR and random effects RR appear to be reasonably constant across different baseline risks. Given the interpretational and arithmetic ease of RR, clinicians may wis...

Are #RelativeRisks overwhelmingly similar across risk groups? And if so, can we personalize care by applying relative risk to individual patients’ risk profiles? This key #EBM study demonstrates that the answer to both questions is an unquestionable YES.
pubmed.ncbi.nlm.nih.gov/11914297/

Trustworthiness of treatment clinical practice guidelines has modestly improved since the introduction of Institute of Medicine standards: a systematic survey - PubMed As assessed by the modified NEATS instrument, although trustworthiness of treatment guidelines has improved after the introduction of IOM standards, improvements proved modest and post-IOM guidelines ...

A survey addresses #guidelines trustworthiness evolution 2010 to 2022. Glass half empty - modest improvement, long way to go; and half full - almost 20% high trustworthiness. Thousands published yearly, astute clinicians will find quality guidelines relevant to them
pubmed.ncbi.nlm.nih.gov/40889618/

Studies being published checking whether #LLMs and other #generativeAI models provide good health advice. #Clinicians, #Researchers, #Reviewers, #Editors, #Publishers can check and optimize studies through the #CHART checklist, abstract checklist, and methodological diagram.
chartguideline.org

Potential impact of missing outcome data on treatment effects in systematic reviews: imputation study - PubMed Even when applying plausible assumptions to the outcomes of participants with definite missing data, the average change in pooled relative effect estimate is substantive, and almost a quarter (22%) of...

When applying plausible assumptions to the outcomes of participants with definite missing data to 100 #SystematicReviews, the average change in pooled relative effect estimate was substantive.

#BMJ #EBM #Medicine

pubmed.ncbi.nlm.nih.gov/32847800/

Author of reviews of gender affirming care decries ‘egregious misuse’ of the findings to justify bans Gordon Guyatt, a co-author of systematic reviews of gender-affirming care, calls use of the findings to justify banning care "egregious."

My research of #GenderAffirming care following #EBM principles have engendered attacks by trans activists, anti-trans activists, and journalists advocating denial of gender-affirming care. Fortunately, some journalists present a balanced account. Here is one.
www.statnews.com/2025/09/22/e...

Recently completed biking vacation with Maureen in Portugal. It’s a wonderful country!

Pooling health-related quality of life outcomes in meta-analysis-a tutorial and review of methods for enhancing interpretability - PubMed - The use of these approaches may enhance the interpretability and the usefulness of systematic reviews involving HRQL outcomes. Copyright © 2011 John Wiley & Sons, Ltd.

Pooling health-related #QualityofLife outcomes in #MetaAnalysis in ways that enhance #interpretability provides a big challenge. This tutorial shows you the statistical methods for achieving the goal.

pubmed.ncbi.nlm.nih.gov/26061786/

GRADE Guidelines 28: Use of GRADE for the assessment of evidence about prognostic factors: rating certainty in identification of groups of patients with different absolute risks - PubMed The same principles GRADE proposed for bodies of evidence addressing treatment and overall prognosis work well in assessing individual prognostic factors, both in noncontextualized and contextualized ...

#GRADE’s primary focus in #SystematicReviews has been on rating certainty in evidence on interventions. But in this article GRADE also provides guidance for #CertaintyofEvidence in #prognosis in which #ObservationalStudies start as high certainty evidence.

pubmed.ncbi.nlm.nih.gov/31982539/

At the recent #GuidelinesInternationalNetwork (GIN) meeting in Geneva I paid the price for my notoriety as folks cornered me, including this group lining up to have their photo taken with me.

At recent #GuidelinesInternationalNetwork (GIN) meeting with Thomas Agoritsas, Chair of the #MAGICEcosytemFoundation and international #GRADE methodology leader and our researcher Prashanti Eachempati, creator of the JUDGE instrument that will revolutionize GRADE education and practice.

Development of a self-reported Chronic Respiratory Questionnaire (CRQ-SR) - PubMed The CRQ-SR is a reproducible, reliable, and stable measure of health status. It compares well with the CRQ-IL but cannot be used interchangeably. The main advantage of the CRQ-SR over the CRQ-IL is th...

The #ChronicRespiratoryQuestionnaire (CRQ) is the most responsive and valid #HealthStatusMeasurement instrument for disease-specific #QualityOfLife in patients with #COPD and other chronic respiratory conditions. This paper presents a self-report version.

pubmed.ncbi.nlm.nih.gov/11713359/

Large Language Models for Chatbot Health Advice Studies: A Systematic Review - PubMed In this systematic review of 137 chatbot health advice studies, the reporting quality was heterogeneous and may inform the development of the CHART reporting standards. Ethical, regulatory, and patien...

Clinicians increasingly rely on #chatbots for advice in managing patients. But is this advice helpful or misleading? Researchers are trying to find out. A survey of 137 studies of bot performance demonstrates their methods leave a great deal to be desired.
pubmed.ncbi.nlm.nih.gov/39903463/

Why Core GRADE is needed: introduction to a new series in The BMJ - PubMed Why Core GRADE is needed: introduction to a new series in The BMJ

I am keen that the Core #GRADE series - 7 articles in
@bmj.com this spring - gets optimal use. I will therefore be available to address queries anyone has about using Core GRADE. Don’t hesitate to ask at guyatt@mcmaster.ca.

pubmed.ncbi.nlm.nih.gov/40233981/

#TransActivists suggest our #SystematicReviews showing low certainty evidence for outcomes of #GenderAffirming care are “pseudoscientce”. The right attacks because we suggest that banning trans care is unconscionable. This newspaper article provides a balanced perspective.
archive.ph/WsBIN

GRADE guidelines: 21 part 2. Test accuracy: inconsistency, imprecision, publication bias, and other domains for rating the certainty of evidence and presenting it in evidence profiles and summary of f... Using GRADE in Cochrane and other reviews as well as World Health Organization and other guidelines helped refining the GRADE approach for rating the certainty of a body of evidence from TA studies. A...

#GRADE provides guidance for rating #CertaintyofEvidence regarding accuracy of diagnostic tests. This informative paper provides details on assessing #inconsistency, #imprecision, #PublicationBias and other domains and for creating #SummaryofFindings tables.

pubmed.ncbi.nlm.nih.gov/32058069/

GRADE Guidelines: 16. GRADE evidence to decision frameworks for tests in clinical practice and public health - PubMed EtD frameworks for developing recommendations and making decisions about tests lay out the sequential steps in reviewing and assessing the different types of evidence that need to be linked.

Most #GRADE users are familiar with GRADE’s #EvidenceToDecision frameworks for interventions. Less so with EtD for tests. This excellent exposition provides guidance when creating or using a #DiagnosticTests and other tests (such as #screening) EtDs.

pubmed.ncbi.nlm.nih.gov/26931285/

Amy Hamm: Father of 'evidence-based medicine' turns his back on science Bullied by activists, Gordon Guyatt is now arguing against using his own findings to guide policy

Our group posted: using our #GRADE #SR of #GenderAffirming care to justify denial of care is unconscionable. A #NationalPost piece decried our position. The author had been suspended by the BC College of Nursing for comments derogatory towards transgender people!
nationalpost.com/opinion/fath...

FCHR Milestone 20th year of The Henry G. Friesen International Prize in Health Research

As winner of the 2024 Canadian #Friesen prize, I toured 8 Canadian universities delivering Friesen lectures on the past and future of #EvidenceBasedMedicine. A booklet summarizing the lecture is now available.

fchr.ca/books

Diagnosis of iron-deficiency anemia in the elderly - PubMed Thirty-six percent of our patients had no demonstrable marrow iron and were classified as being iron-deficient. The serum ferritin was the best test for distinguishing those with iron deficiency from ...

This classic article looking at #DiagnosticTests for iron deficiency #anemia (showed #ferritin by far the best) remains the best example to teach students how to use #LikelihoodRatios in their clinical practice.

pubmed.ncbi.nlm.nih.gov/2178409/

How the world has changed, how quickly we take for granted technological miracles that not so long ago would have been the stuff of #ScienceFiction. Only few years ago, a colleague called his research fellow over to view the miracle of his computer screen that showed six talking faces. And now…

A critical look at transition ratings - PubMed Patient ratings of the extent to which they have improved or deteriorated-transition ratings-are extremely common in clinical practice and clinical research. However, some have raised concerns about t...

#TransitionRatings (are you better; if so how much) is the most-used strategy for establishing #MinimalImportantDifferences in #PatientReportedOutcomeMeasures. But transition ratings must be valid. This seminal, essential paper shows how to test their validity.
pubmed.ncbi.nlm.nih.gov/12393078/

Hanlon's Razor: Not Everyone is Out to Get You Hanlon’s razor is a mental safeguard against the temptation to label behavior as malicious when incompetence is the most common response

Hanlon's Razor is a principle stating, "Never attribute to malice that which is adequately explained by incompetence". I’ve recently had an experience that put me in mind of these wise words – I suspected malevolence; explanation proved otherwise.

fs.blog/mental-model...

Commentary--goodbye M(C)ID! Hello MID, where do you come from? - PubMed Commentary--goodbye M(C)ID! Hello MID, where do you come from?

We chose the term #MinimalClinicallyImportantDifference in an era of medical paternalism. We subsequently realized that we are considering patient-important outcomes and our language should align. This article presents the transition to #MinimallyImportantDifference
pubmed.ncbi.nlm.nih.gov/15762909/

Legislators have unconscionably misused our #SystematicReviews of #GenderTransition interventions to deny #PatientsCare. Formerly, I thought my job ended with conducting and reporting high quality research. I now realize I have an additional responsibility to address how my work is used.

The GRADE Evidence to Decision (EtD) framework for health system and public health decisions - PubMed This framework provides a structured and transparent approach to support policy-making informed by the best available research evidence, while making the basis for decisions accessible to those whom t...

The #GRADE evidence to decision (EtD) framework provides invaluable guidance in moving from evidence to recommendations. There are a number of variations for specific areas. This article explains EtD frameworks for #HealthSystem and policy decisions.
pubmed.ncbi.nlm.nih.gov/29843743/

A Call for Reckoning and Reform in Interventional Pain Medicine and Neuromodulation Research

Recent BMJ: strong rapid recommendation against lucrative interventional #pain intervention. Practitioners pushed back, but this enlightened exception acknowledges industry influence, catchy branding ignoring science, hidden COI, low quality research.

pmc.ncbi.nlm.nih.gov/articles/PMC...

Clinical impact versus factor analysis for quality of life questionnaire construction - PubMed Although some items were the same for both methods, there were also some important differences. Different approaches to item reduction led to appreciably different instruments.

As this article demonstrates, when one is creating a health status measurement #instrument for use in #Clinicaltrials, factor analysis has major limitations. Far preferable to pick items patients think are important than to choose on the basis of factor structure.
pubmed.ncbi.nlm.nih.gov/9120521/

Recommendations for the development, implementation, and reporting of control interventions in efficacy and mechanistic trials of physical, psychological, and self-management therapies: the CoPPS Stat... Recommendations for the development, implementation, and reporting of control interventions in efficacy and mechanistic trials of physical, psychological, and self-management therapies: the CoPPS Stat...

Explanatory or mechanistic #RCTs of physical or psychological interventions requires “placebo,” or “sham” comparators. This @bmj.com article presents recommendations for designing, and reporting comparator interventions as well as a reporting checklist.
pubmed.ncbi.nlm.nih.gov/37230508/