MétaCan
Menu
Back to cohort
Record W2939670107 · doi:10.1093/aje/kwz100

Effect Estimates in Randomized Trials and Observational Studies: Comparing Apples With Apples

2019· article· en· W2939670107 on OpenAlexaff
Sara Lodi, Andrew Phillips, Jens Lundgren, Roger Logan, Shweta Sharma, Stephen R. Cole, Abdel Babiker, Matthew Law, Haitao Chu, Dana Byrne, Andrzéj Horban, Jonathan A C Sterne, Kholoud Porter, Caroline Sabin, Dominique Costagliola, Sophie Abgrall, M. John Gill, Giota Touloumi, Antônio Guilherme Pacheco, Ard van Sighem, Peter Reiss, Heiner C. Bucher, Alexandra Montoliu Giménez, Inmaculada Jarrín, Linda Wittkop, Laurence Meyer, Santiago Pérez‐Hoyos, Amy C. Justice, James D. Neaton, Miguel A. Hernán

Bibliographic record

VenueAmerican Journal of Epidemiology · 2019
Typearticle
Languageen
FieldMathematics
TopicAdvanced Causal Inference Techniques
Canadian institutionsAlberta Hip and Knee ClinicUniversity of Calgary
FundersCilagNational Institute of Allergy and Infectious DiseasesInstituto de Salud Carlos IIINational Center for Advancing Translational SciencesMedical Research CouncilUniversity of North Carolina at Chapel HillNational Institutes of HealthU.S. Department of DefenseUniversité de BordeauxCenter for AIDS Research, University of WashingtonUniformed Services University of the Health SciencesUniversiteit van AmsterdamGilead SciencesUniversity of BristolUniwersytet WarszawskiUniversity College LondonHarvard T.H. Chan School of Public HealthNational Institute for Health and Care ResearchRowan UniversityRigshospitaletNational and Kapodistrian University of AthensBill and Melinda Gates FoundationViiV HealthcareUniversität BaselCentre Hospitalier Universitaire de BordeauxStichting HIV MonitoringWarszawski Uniwersytet MedycznyHarvard University Center for AIDS ResearchHarvard UniversityYale UniversitySorbonne UniversitéInstitut National de la Santé et de la Recherche MédicaleUniversity of Minnesota
KeywordsObservational studyRandomized controlled trialMedicineInternal medicine

Abstract

fetched live from OpenAlex

Effect estimates from randomized trials and observational studies might not be directly comparable because of differences in study design, other than randomization, and in data analysis. We propose a 3-step procedure to facilitate meaningful comparisons of effect estimates from randomized trials and observational studies: 1) harmonization of the study protocols (eligibility criteria, treatment strategies, outcome, start and end of follow-up, causal contrast) so that the studies target the same causal effect, 2) harmonization of the data analysis to estimate the causal effect, and 3) sensitivity analyses to investigate the impact of discrepancies that could not be accounted for in the harmonization process. To illustrate our approach, we compared estimates of the effect of immediate with deferred initiation of antiretroviral therapy in individuals positive for the human immunodeficiency virus from the Strategic Timing of Antiretroviral Therapy (START) randomized trial and the observational HIV-CAUSAL Collaboration.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

How this classification was reachedexpand

Full frame machine prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.

metaresearch head score (Codex)0.501
metaresearch head score (Gemma)0.763
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesMetaresearch
Consensus categoriesMetaresearch
DomainCandidate signal: Methods · Consensus signal: Methods
Study designCandidate signal: Theoretical or conceptual · Consensus signal: Theoretical or conceptual
GenreCandidate signal: Methods · Consensus signal: Methods
Teacher disagreement score0.499
Threshold uncertainty score0.615

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.5010.763
Meta-epidemiology (narrow)0.0020.002
Meta-epidemiology (broad)0.0100.011
Bibliometrics0.0090.012
Science and technology studies0.0010.010
Scholarly communication0.0100.012
Open science0.0050.008
Research integrity0.0060.013
Insufficient payload (model declined to judge)0.0070.001

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.425
GPT teacher head0.532
Teacher spread0.107 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; the direct Gemma label and the distilled Codex classifier agree on what is shown here.

Study designTheoretical or conceptual
DomainMethods
GenreMethods

How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".

Quick stats

Citations115
Published2019
Admission routes1
Has abstractyes

Explore more

Same venueAmerican Journal of EpidemiologySame topicAdvanced Causal Inference TechniquesFrench-language works237,207