Individual Participant Data Meta-Analysis for a Binary Outcome: One-Stage or Two-Stage?
Publication Date
April 09, 2013
Journal
PLOS ONE
Authors
Thomas P. A. Debray, Karel G. M. Moons, Ghada Mohammed Abdallah Abo Zaid, Hendrik Koffijberg, et al
Volume
8
Issue
4
Pages
e60650
DOI
https://dx.plos.org/10.1371/journal.pone.0060650
Publisher URL
http://journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0060650
PubMed
http://www.ncbi.nlm.nih.gov/pubmed/23585842
PubMed Central
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3621872
Europe PMC
http://europepmc.org/abstract/MED/23585842
Web of Science
000317909600032
Scopus
84876028745
Mendeley
http://www.mendeley.com/research/individual-participant-data-metaanalysis-binary-outcome-onestage-twostage
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Mendeley | Further Information

{"title"=>"Individual Participant Data Meta-Analysis for a Binary Outcome: One-Stage or Two-Stage?", "type"=>"journal", "authors"=>[{"first_name"=>"Thomas P.A.", "last_name"=>"Debray", "scopus_author_id"=>"54879335700"}, {"first_name"=>"Karel G.M.", "last_name"=>"Moons", "scopus_author_id"=>"7004546169"}, {"first_name"=>"Ghada Mohammed Abdallah", "last_name"=>"Abo-Zaid", "scopus_author_id"=>"35602627900"}, {"first_name"=>"Hendrik", "last_name"=>"Koffijberg", "scopus_author_id"=>"24465689600"}, {"first_name"=>"Richardvid", "last_name"=>"Da Riley", "scopus_author_id"=>"55648228100"}], "year"=>2013, "source"=>"PLoS ONE", "identifiers"=>{"issn"=>"19326203", "scopus"=>"2-s2.0-84876028745", "sgr"=>"84876028745", "pui"=>"368705030", "isbn"=>"1932-6203", "pmid"=>"23585842", "doi"=>"10.1371/journal.pone.0060650"}, "id"=>"36aa99de-86dd-32d6-a199-5c41978a5305", "abstract"=>"BACKGROUND: A fundamental aspect of epidemiological studies concerns the estimation of factor-outcome associations to identify risk factors, prognostic factors and potential causal factors. Because reliable estimates for these associations are important, there is a growing interest in methods for combining the results from multiple studies in individual participant data meta-analyses (IPD-MA). When there is substantial heterogeneity across studies, various random-effects meta-analysis models are possible that employ a one-stage or two-stage method. These are generally thought to produce similar results, but empirical comparisons are few. OBJECTIVE: We describe and compare several one- and two-stage random-effects IPD-MA methods for estimating factor-outcome associations from multiple risk-factor or predictor finding studies with a binary outcome. One-stage methods use the IPD of each study and meta-analyse using the exact binomial distribution, whereas two-stage methods reduce evidence to the aggregated level (e.g. odds ratios) and then meta-analyse assuming approximate normality. We compare the methods in an empirical dataset for unadjusted and adjusted risk-factor estimates. RESULTS: Though often similar, on occasion the one-stage and two-stage methods provide different parameter estimates and different conclusions. For example, the effect of erythema and its statistical significance was different for a one-stage (OR = 1.35, [Formula: see text]) and univariate two-stage (OR = 1.55, [Formula: see text]). Estimation issues can also arise: two-stage models suffer unstable estimates when zero cell counts occur and one-stage models do not always converge. CONCLUSION: When planning an IPD-MA, the choice and implementation (e.g. univariate or multivariate) of a one-stage or two-stage method should be prespecified in the protocol as occasionally they lead to different conclusions about which factors are associated with outcome. Though both approaches can suffer from estimation challenges, we recommend employing the one-stage method, as it uses a more exact statistical approach and accounts for parameter correlation.", "link"=>"http://www.mendeley.com/research/individual-participant-data-metaanalysis-binary-outcome-onestage-twostage", "reader_count"=>72, "reader_count_by_academic_status"=>{"Professor > Associate Professor"=>5, "Librarian"=>1, "Researcher"=>20, "Student > Doctoral Student"=>2, "Student > Ph. D. Student"=>23, "Student > Postgraduate"=>6, "Other"=>5, "Student > Master"=>5, "Student > Bachelor"=>2, "Lecturer"=>1, "Lecturer > Senior Lecturer"=>2}, "reader_count_by_user_role"=>{"Professor > Associate Professor"=>5, "Librarian"=>1, "Researcher"=>20, "Student > Doctoral Student"=>2, "Student > Ph. D. Student"=>23, "Student > Postgraduate"=>6, "Other"=>5, "Student > Master"=>5, "Student > Bachelor"=>2, "Lecturer"=>1, "Lecturer > Senior Lecturer"=>2}, "reader_count_by_subject_area"=>{"Unspecified"=>4, "Agricultural and Biological Sciences"=>6, "Arts and Humanities"=>1, "Business, Management and Accounting"=>3, "Computer Science"=>1, "Engineering"=>2, "Nursing and Health Professions"=>1, "Mathematics"=>6, "Medicine and Dentistry"=>38, "Design"=>1, "Pharmacology, Toxicology and Pharmaceutical Science"=>1, "Psychology"=>5, "Social Sciences"=>2, "Immunology and Microbiology"=>1}, "reader_count_by_subdiscipline"=>{"Medicine and Dentistry"=>{"Medicine and Dentistry"=>38}, "Social Sciences"=>{"Social Sciences"=>2}, "Psychology"=>{"Psychology"=>5}, "Mathematics"=>{"Mathematics"=>6}, "Unspecified"=>{"Unspecified"=>4}, "Pharmacology, Toxicology and Pharmaceutical Science"=>{"Pharmacology, Toxicology and Pharmaceutical Science"=>1}, "Arts and Humanities"=>{"Arts and Humanities"=>1}, "Design"=>{"Design"=>1}, "Engineering"=>{"Engineering"=>2}, "Immunology and Microbiology"=>{"Immunology and Microbiology"=>1}, "Agricultural and Biological Sciences"=>{"Agricultural and Biological Sciences"=>6}, "Computer Science"=>{"Computer Science"=>1}, "Business, Management and Accounting"=>{"Business, Management and Accounting"=>3}, "Nursing and Health Professions"=>{"Nursing and Health Professions"=>1}}, "reader_count_by_country"=>{"Canada"=>1, "Netherlands"=>1, "Belgium"=>1, "Norway"=>1, "Japan"=>1, "Finland"=>1, "United Kingdom"=>2, "Italy"=>1, "France"=>1, "Australia"=>1}, "group_count"=>2}

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Scopus | Further Information

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Figshare

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  • {"files"=>["https://ndownloader.figshare.com/files/1020236"], "description"=>"<p>Estimated factor-outcome associations in the DVT case study for <i>ddimdich</i>, adjusted for <i>malign</i>, <i>surg</i> and <i>calfdif3</i>.</p>", "links"=>[], "tags"=>["statistics", "Biostatistics", "Confidence intervals", "Statistical methods", "Clinical research design", "meta-analyses", "epidemiology", "Biomarker epidemiology", "Clinical epidemiology", "Epidemiological methods", "Non-clinical medicine", "Health care policy", "Health risk analysis", "factor-outcome", "associations", "dvt", "adjusted"], "article_id"=>679190, "categories"=>["Mathematics", "Medicine"], "users"=>["Thomas P. A. Debray", "Karel G. M. Moons", "Ghada Mohammed Abdallah Abo-Zaid", "Hendrik Koffijberg", "Richard David Riley"], "doi"=>["https://dx.doi.org/10.1371/journal.pone.0060650.t003"], "stats"=>{"downloads"=>0, "page_views"=>0, "likes"=>0}, "figshare_url"=>"https://figshare.com/articles/_Estimated_factor_outcome_associations_in_the_DVT_case_study_for_ddimdich_adjusted_for_malign_surg_and_calfdif3_/679190", "title"=>"Estimated factor-outcome associations in the DVT case study for <i>ddimdich</i>, adjusted for <i>malign</i>, <i>surg</i> and <i>calfdif3</i>.", "pos_in_sequence"=>0, "defined_type"=>3, "published_date"=>"2013-04-09 02:33:10"}
  • {"files"=>["https://ndownloader.figshare.com/files/1020237"], "description"=>"<p>The number between brackets indicates the amount of available studies. Statistical significance (<i>p</i>-value), 95% confidence intervals (95% CI) and 95% prediction intervals (95% PI) are given for the odds ratio (OR). For some one-stage models, estimates could not be obtained because the adaptive Gauss-Hermite approximation did not converge.</p>†<p>Zero-cells occurred in two studies for factor <i>oachst</i>.</p>", "links"=>[], "tags"=>["statistics", "Biostatistics", "Confidence intervals", "Statistical methods", "Clinical research design", "meta-analyses", "epidemiology", "Biomarker epidemiology", "Clinical epidemiology", "Epidemiological methods", "Non-clinical medicine", "Health care policy", "Health risk analysis", "unadjusted", "factor-outcome", "associations", "dvt"], "article_id"=>679191, "categories"=>["Mathematics", "Medicine"], "users"=>["Thomas P. A. Debray", "Karel G. M. Moons", "Ghada Mohammed Abdallah Abo-Zaid", "Hendrik Koffijberg", "Richard David Riley"], "doi"=>["https://dx.doi.org/10.1371/journal.pone.0060650.t002"], "stats"=>{"downloads"=>0, "page_views"=>0, "likes"=>0}, "figshare_url"=>"https://figshare.com/articles/_Estimated_unadjusted_factor_outcome_associations_for_the_DVT_case_study_/679191", "title"=>"Estimated unadjusted factor-outcome associations for the DVT case study.", "pos_in_sequence"=>0, "defined_type"=>3, "published_date"=>"2013-04-09 02:33:11"}
  • {"files"=>["https://ndownloader.figshare.com/files/1020238", "https://ndownloader.figshare.com/files/1020239", "https://ndownloader.figshare.com/files/1020240", "https://ndownloader.figshare.com/files/1020242"], "description"=>"<div><p>Background</p><p>A fundamental aspect of epidemiological studies concerns the estimation of factor-outcome associations to identify risk factors, prognostic factors and potential causal factors. Because reliable estimates for these associations are important, there is a growing interest in methods for combining the results from multiple studies in individual participant data meta-analyses (IPD-MA). When there is substantial heterogeneity across studies, various random-effects meta-analysis models are possible that employ a one-stage or two-stage method. These are generally thought to produce similar results, but empirical comparisons are few.</p><p>Objective</p><p>We describe and compare several one- and two-stage random-effects IPD-MA methods for estimating factor-outcome associations from multiple risk-factor or predictor finding studies with a binary outcome. One-stage methods use the IPD of each study and meta-analyse using the exact binomial distribution, whereas two-stage methods reduce evidence to the aggregated level (e.g. odds ratios) and then meta-analyse assuming approximate normality. We compare the methods in an empirical dataset for unadjusted and adjusted risk-factor estimates.</p><p>Results</p><p>Though often similar, on occasion the one-stage and two-stage methods provide different parameter estimates and different conclusions. For example, the effect of erythema and its statistical significance was different for a one-stage (OR = 1.35, ) and univariate two-stage (OR = 1.55, ). Estimation issues can also arise: two-stage models suffer unstable estimates when zero cell counts occur and one-stage models do not always converge.</p><p>Conclusion</p><p>When planning an IPD-MA, the choice and implementation (e.g. univariate or multivariate) of a one-stage or two-stage method should be prespecified in the protocol as occasionally they lead to different conclusions about which factors are associated with outcome. Though both approaches can suffer from estimation challenges, we recommend employing the one-stage method, as it uses a more exact statistical approach and accounts for parameter correlation.</p></div>", "links"=>[], "tags"=>["statistics", "Biostatistics", "Confidence intervals", "Statistical methods", "Clinical research design", "meta-analyses", "epidemiology", "Biomarker epidemiology", "Clinical epidemiology", "Epidemiological methods", "Non-clinical medicine", "Health care policy", "Health risk analysis", "meta-analysis", "binary", "one-stage"], "article_id"=>679192, "categories"=>["Mathematics", "Medicine"], "users"=>["Thomas P. A. Debray", "Karel G. M. Moons", "Ghada Mohammed Abdallah Abo-Zaid", "Hendrik Koffijberg", "Richard David Riley"], "doi"=>["https://dx.doi.org/10.1371/journal.pone.0060650.s001", "https://dx.doi.org/10.1371/journal.pone.0060650.s002", "https://dx.doi.org/10.1371/journal.pone.0060650.s003", "https://dx.doi.org/10.1371/journal.pone.0060650.s004"], "stats"=>{"downloads"=>0, "page_views"=>0, "likes"=>0}, "figshare_url"=>"https://figshare.com/articles/_Individual_Participant_Data_Meta_Analysis_for_a_Binary_Outcome_One_Stage_or_Two_Stage_/679192", "title"=>"Individual Participant Data Meta-Analysis for a Binary Outcome: One-Stage or Two-Stage?", "pos_in_sequence"=>0, "defined_type"=>4, "published_date"=>"2013-04-09 02:33:12"}

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Relative Metric

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