A decade of individual participant data meta-analyses: A review of current practice

doi:10.1016/j.cct.2015.06.012

Contemporary Clinical Trials

Volume 45, Part A, November 2015, Pages 76-83

https://doi.org/10.1016/j.cct.2015.06.012 Get rights and content

Abstract

Introduction

Individual participant data (IPD) systematic reviews and meta-analyses are often considered to be the gold standard for meta-analysis. In the ten years since the first review into the methodology and reporting practice of IPD reviews was published much has changed in the field. This paper investigates current reporting and statistical practice in IPD systematic reviews.

Methods

A systematic review was performed to identify systematic reviews that collected and analysed IPD. Data were extracted from each included publication on a variety of issues related to the reporting of IPD review process, and the statistical methods used.

Results

There has been considerable growth in the use of “one-stage” methods to perform IPD meta-analyses. The majority of reviews consider at least one covariate other than the primary intervention, either using subgroup analysis or including covariates in one-stage regression models. Random-effects analyses, however, are not often used.

Reporting of review methods was often limited, with few reviews presenting a risk-of-bias assessment. Details on issues specific to the use of IPD were little reported, including how IPD were obtained; how data was managed and checked for consistency and errors; and for how many studies and participants IPD were sought and obtained.

Conclusion

While the last ten years have seen substantial changes in how IPD meta-analyses are performed there remains considerable scope for improving the quality of reporting for both the process of IPD systematic reviews, and the statistical methods employed in them. It is to be hoped that the publication of the PRISMA-IPD guidelines specific to IPD reviews will improve reporting in this area.

Introduction

The aim of individual participant data (IPD) systematic reviews and meta-analyses is to obtain all the original, raw participant data from all studies on a specified topic, in order to reanalyse the data and pool it across studies. While obtaining all the original data from all relevant studies may be time consuming and difficult, IPD meta-analysis is recognised as having many advantages over meta-analysis based on data reported in publications, and is considered the “gold standard” for meta-analysis [1], [2], [3].

Ten years ago the first review of the practice and reporting of individual participant data meta-analyses was published in Clinical Trials [4]. At that time IPD meta-analysis was still in its early stages with numbers of publications being limited before the late 1990s. The development of statistical methods in the area was also in its infancy, with key methods papers having been published only a few years before [5], [6], [7]. The review found that reporting of the processes of IPD meta-analyses was generally poor, particularly with regard to how much of the total IPD was obtained for analysis, and with poor reporting of statistical methods. Statistical analysis was also limited, with little investigation of heterogeneity, and most meta-analyses focussing on calculating overall treatment effects, with little consideration given to subgroup analyses, or how factors such as a participant's age might modify the effectiveness of a treatment. Another review performed in 2008 and published in 2010 [8] came to broadly similar conclusions.

In the ten years since that first review was published much has changed. The number of systematic reviews and meta-analyses published continues to grow, and consequently IPD meta-analysis has also grown in popularity. Advances in computing have also made meta-analyses easier to perform; most methods for IPD meta-analysis can now be implemented in all major statistical software packages. As the number of IPD meta-analyses grows there is an increased need to ensure high quality of conduct reporting of these analyses, to avoid some of the problems identified in the original review.

The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement [9] is widely used as guidance on how to report a systematic review and meta-analysis. Recently a new PRISMA-IPD statement has been released specifically to guide the conduct and reporting of IPD reviews and meta-analyses [10]. As part of the process of creating this statement, a review of current practice in reporting of IPD reviews was conducted to identify areas where reporting was poor to inform development of the guidance. This paper presents the results of this review, updated to 2014, and expanded to consider statistical methods used in IPD meta-analyses.

Section snippets

Methods

The aim of this review was to identify published systematic reviews of medical interventions that sought to obtain and meta-analyse IPD. It was intended to obtain a representative sample of recent reviews for analysis, rather than find all such reviews, so an exhaustive database search was not performed. A MEDLINE search was performed including terms “individual participant/patient data”, “meta-analysis” and “systematic review”. This search was originally performed in January 2013 and was

Results

The original and updated search together identified 1371 potentially relevant records. After checking titles and abstracts 184 papers were considered for inclusion. After obtaining full texts (where readily available) and further checking, 100 systematic reviews of IPD were included in this review [11], [12], [13], [14], [15], [16], [17], [18], [19], [20], [21], [22], [23], [24], [25], [26], [27], [28], [29], [30], [31], [32], [33], [34], [35], [36], [37], [38], [39], [40], [41], [42], [43],

Quality of reporting

The included reviews varied considerably in how they reported aspects of the review process, such as the search strategy, and quality assessment process. The numbers of reviews reporting key aspects of the IPD review process are summarised in Table 1. In general, aspects of the review process common to all systematic reviews were well reported, with, for example, 80% of reviews reporting details of the search strategy and search process. Inclusion and exclusion criteria were also generally

Statistical methods

The review of 2005 identified two distinct statistical approaches for IPD meta-analysis [4]. In a two-stage approach studies are analysed individually to obtain summary results for each study in the first stage, and the summary results pooled across studies as in a conventional meta-analysis in the second stage. In a one-stage approach all data from all studies are analysed simultaneously, in a single model, usually a regression model. This distinction in approaches remains in current practice.

Discussion

Much has changed in IPD systematic reviews and meta-analyses in the last ten years. The most notable change is the switch from a predominance of two-stage methods, where studies are analysed separately and summary results poled across studies; to one-stage methods where all IPD are analysed simultaneously. This is probably driven by growing familiarity with these methods, improved software, and recognition that regression models offer the greatest flexibility for IPD analysis. Another key

Conclusion

The last ten years have seen substantial changes in how IPD meta-analyses are performed, particularly with the growth of the use of one-stage regression models. There remains considerable scope for improving the quality of reporting both the process of IPD systematic reviews, and the statistical methods employed in them. It is to be hoped that the publication of the PRISMA-IPD guidelines specific to IPD reviews will improve reporting in this area [10].

Funding

The systematic review described in this paper was performed, in part, to inform the development of PRISMA-IPD. That project was supported, in part, through a National Institute for Health Research (NIHR) Senior Investigator personal award (Dr L. Stewart), and as part of the MRC–National Institute for Health Research Methodology Research Programme (grant ID 88053). The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data;

Acknowledgements

We would like to thank Kath Wright for performing the literature searches for this review, and Dean Langan and Alison Smith for their assistance in the study selection and data extraction processes. We also thank the members of the PRISMA-IPD development group for their comments on early versions of this review.

References (112)

L.A. Stewart et al.
Meta-analysis of the literature or of individual patient data: is there a difference?
Lancet
(1993)
J.M. Bae et al.
Mohs micrographic surgery for extramammary Paget disease: a pooled analysis of individual patient data
J. Am. Acad. Dermatol.
(2013)
Y. Ben-Shlomo et al.
Aortic pulse wave velocity improves cardiovascular event prediction: an individual participant meta-analysis of prospective observational data from 17,635 subjects
J. Am. Coll. Cardiol.
(2014)
S.S. Brar et al.
Impact of platelet reactivity on clinical outcomes after percutaneous coronary intervention. A collaborative meta-analysis of individual participant data
J. Am. Coll. Cardiol.
(2011)
A.J. Breugom et al.
Adjuvant chemotherapy after preoperative (chemo)radiotherapy and surgery for patients with rectal cancer: a systematic review and meta-analysis of individual patient data
Lancet Oncol.
(2015)
M. Buyse et al.
Individual patient data meta-analysis of randomized trials evaluating IL-2 monotherapy as remission maintenance therapy in acute myeloid leukemia
Blood
(2011)
M. Flather et al.
The effect of age on outcomes of coronary artery bypass surgery compared with balloon angioplasty or bare-metal stent implantation among patients with multivessel coronary disease: a collaborative analysis of individual patient data from 10 randomized trials
J. Am. Coll. Cardiol.
(2012)
K.A.A. Fox et al.
Long-term outcome of a routine versus selective invasive strategy in patients with non-ST-segment elevation acute coronary syndrome a meta-analysis of individual patient data
J. Am. Coll. Cardiol.
(2010)
L.L. Gluud et al.
Oral branched-chain amino acids have a beneficial effect on manifestations of hepatic encephalopathy in a systematic review with meta-analyses of randomized controlled trials
J. Nutr.
(2013)
M.A. Hlatky et al.
Coronary artery bypass surgery compared with percutaneous coronary interventions for multivessel disease: a collaborative analysis of individual patient data from ten randomised trials
Lancet
(2009)

M.W.J. Koeter et al.

Effect of early and late compliance on the effectiveness of acamprosate in the treatment of alcohol dependence

J. Subst. Abus. Treat.

(2010)

S. Kufner et al.

A meta-analysis of specifically designed randomized trials of sirolimus-eluting versus paclitaxel-eluting stents in diabetic patients with coronary artery disease

Am. Heart J.

(2011)

S. Laporte et al.

Individual patient data meta-analysis of enoxaparin vs. unfractionated heparin for venous thromboembolism prevention in medical patients

J. Thromb. Haemost.

(2011)

P. Lehert et al.

Racecadotril for childhood gastroenteritis: an individual patient data meta-analysis

Dig. Liver Dis.

(2011)

M.N. Mavros et al.

A systematic review: treatment and prognosis of patients with fibrolamellar hepatocellular carcinoma

J. Am. Coll. Surg.

(2012)

W.G. Melsen et al.

Attributable mortality of ventilator-associated pneumonia: a meta-analysis of individual patient data from randomised prevention studies

Lancet Infect. Dis.

(2013)

S.G. Muthuri et al.

Effectiveness of neuraminidase inhibitors in reducing mortality in patients admitted to hospital with influenza A H1N1pdm09 virus infection: a meta-analysis of individual participant data

Lancet Respir. Med.

(2014)

S.J. Nicholls et al.

Meta-analysis of comparative efficacy of increasing dose of atorvastatin versus rosuvastatin versus simvastatin on lowering levels of atherogenic lipids (from VOYAGER)

Am. J. Cardiol.

(2010)

G.I. Papakostas et al.

Efficacy of bupropion and the selective serotonin reuptake inhibitors in the treatment of anxiety symptoms in major depressive disorder: a meta-analysis of individual patient data from 10 double-blind, randomized clinical trials

J. Psychiatr. Res.

(2008)

F.A. Raja et al.

Platinum versus platinum-combination chemotherapy in platinum-sensitive recurrent ovarian cancer: a meta-analysis using individual patient data

Ann. Oncol.

(2013)

R.N. Rodseth et al.

The prognostic value of pre-operative and post-operative B-type natriuretic peptides in patients undergoing noncardiac surgery: B-type natriuretic peptide and N-terminal fragment of pro-B-type natriuretic peptide: a systematic review and individual patient data meta-analysis

J. Am. Coll. Cardiol.

(2014)

U. Ronellenfitsch et al.

Preoperative chemo(radio)therapy versus primary surgery for gastroesophageal adenocarcinoma: systematic review with meta-analysis combining individual patient and aggregate data

Eur. J. Cancer

(2013)

A. Rossi et al.

Six versus fewer planned cycles of first-line platinum-based chemotherapy for non-small-cell lung cancer: a systematic review and meta-analysis of individual patient data

Lancet Oncol.

(2014)

L. Stewart et al.

To IPD or not to IPD?

Eval. Health Prof.

(2002)

L.A. Stewart et al.

Practical methodology of meta-analyses (overviews) using updated individual patient data

Stat. Med.

(1995)

M.C. Simmonds et al.

Meta-analysis of individual patient data from randomized trials; a review of methods used in practice

Cinical Trials

(2005)

J.P.T. Higgins et al.

Meta-analysis of continuous outcome data from individual patients

Stat. Med.

(2001)

R.M. Turner et al.

A multilevel model framework for meta-analysis of clinical trials with binary outcomes

Stat. Med.

(2000)

A. Whitehead et al.

Meta-analysis of ordinal outcomes using individual patient data

Stat. Med.

(2001)

R.D. Riley et al.

Meta-analysis of individual participant data: rationale, conduct, and reporting

BMJ

(2010)

D. Moher et al.

Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement

BMJ

(2009)

L.A. Stewart et al.

Preferred reporting items for a systematic review and meta-analysis of individual participant data: the PRISMA-IPD statement

JAMA

(2015)

Antithrombotic Trialists Collaboration et al.

Aspirin in the primary and secondary prevention of vascular disease: collaborative meta-analysis of individual participant data from randomised trials

Lancet

(2009)

A. Auperin et al.

Meta-analysis of concomitant versus sequential radiochemotherapy in locally advanced non-small-cell lung cancer

J. Clin. Oncol.

(2010)

T.S. Baman et al.

Safety of pacemaker reuse: a meta-analysis with implications for underserved nations

Circ.

(2011)

K.J.L. Bell et al.

Monitoring initial response to angiotensin-converting enzyme inhibitor-based regimens: an individual patient data meta-analysis from randomized, placebo-controlled trials

Hypertension

(2010)

K. Bennett et al.

Cognitive behavioral therapy age effects in child and adolescent anxiety: an individual patient data meta-analysis

Depress. Anxiety

(2013)

D.A. Berry et al.

High-dose chemotherapy with autologous stem-cell support as adjuvant therapy in breast cancer: overview of 15 randomized trials

J. Clin. Oncol.

(2011)

A. Beyerlein et al.

Infant formula supplementation with long-chain polyunsaturated fatty acids has no effect on Bayley developmental scores at 18 months of age—IPD meta-analysis of 4 large clinical trials

J. Pediatr. Gastroenterol. Nutr.

(2010)

T. Bongartz et al.

Etanercept therapy in rheumatoid arthritis and the risk of malignancies: a systematic review and individual patient data meta-analysis of randomised controlled trials

Ann. Rheum. Dis.

(2009)

J. Bourhis et al.

Effect of amifostine on survival among patients treated with radiotherapy: a meta-analysis of individual patient data

J. Clin. Oncol.

(2011)

M.F. Brin et al.

Safety and tolerability of onabotulinumtoxinA in the treatment of facial lines: a meta-analysis of individual patient data from global clinical registration studies in 1678 participants

J. Am. Acad. Dermatol.

(2009)

F. Burzotta et al.

Clinical impact of thrombectomy in acute ST-elevation myocardial infarction: an individual patient-data pooled analysis of 11 trials

Eur. Heart J.

(2009)

Systematic review of purine analog treatment for chronic lymphocytic leukemia: lessons for future trials

Haematologica

(2012)

L. Chambrone et al.

Effects of smoking cessation on the outcomes of non-surgical periodontal therapy: a systematic review and individual patient data meta-analysis

J. Clin. Periodontol.

(2013)

Reducing uncertainties about the effects of chemoradiotherapy for cervical cancer: a systematic review and meta-analysis of individual patient data from 18 randomized trials

J. Clin. Oncol.

(2008)

Beneficial and harmful effects of anthracyclines in the treatment of childhood acute lymphoblastic leukaemia: a systematic review and meta-analysis

Br. J. Haematol.

(2009)

R. Clarke et al.

Effects of lowering homocysteine levels with B vitamins on cardiovascular disease, cancer, and cause-specific mortality: meta-analysis of 8 randomized trials involving 37,485 individuals

Arch. Intern. Med.

(2010)

J.P. Daniels et al.

Individual patient data meta-analysis of randomized evidence to assess the effectiveness of laparoscopic uterosacral nerve ablation in chronic pelvic pain

Hum. Reprod. Update

(2010)

T. De Backer et al.

Naftidrofuryl for intermittent claudication: meta-analysis based on individual patient data

BMJ

(2009)

Cited by (82)

Depression screening tool accuracy individual participant data meta-analyses: data contribution was associated with multiple factors
2023, Journal of Clinical Epidemiology
To examine the proportion of eligible primary studies that contributed data, study characteristics associated with data contribution, and reasons for noncontribution using diagnostic test accuracy Individual Participant Data Meta-Analysis (IPDMA) data sets from the DEPRESsion Screening Data project.
We reviewed data set contributions from four IPDMAs. A multivariable logistic regression model was fitted to evaluate study factors associated with data contribution.
Of 456 eligible studies from four included IPDMAs, 295 (65%) contributed data. More recent year of publication and higher journal impact factor were associated with greater odds of data contribution. Studies conducted in Europe (excluding the United Kingdom), Oceania, Canada, the Middle East, Africa, and Central or South America (reference = the United States), that have recruitment from inpatient care or nonmedical settings (reference = outpatient), that reported screening accuracy results, or that drew negative conclusions (reference = positive conclusions) were more likely to contribute data. Studies of the Geriatric Depression Scale (reference = the Patient Health Questionnaire) or lacking funding information were negatively associated with data contribution. Over 80% of noncontributions were due to authors being unreachable or data being unavailable.
The study identified factors associated with data contribution that may support future research to promote data contribution to IPDMAs.
TIPS prevents further decompensation and improves survival in patients with cirrhosis and portal hypertension in an individual patient data meta-analysis
2023, Journal of Hepatology
Further decompensation represents a prognostic stage of cirrhosis associated with higher mortality compared with first decompensation. A transjugular intrahepatic portosystemic shunt (TIPS) is indicated to prevent variceal rebleeding and for refractory ascites, but its overall efficacy to prevent further decompensations is unknown. This study assessed the incidence of further decompensation and mortality after TIPS vs. standard of care (SOC).
Controlled studies assessing covered TIPS compared with SOC for the indication of refractory ascites and prevention of variceal rebleeding published from 2004 to 2020 were considered. We collected individual patient data (IPD) to perform an IPD meta-analysis and to compare the treatment effect in a propensity score (PS)-matched population. Primary outcome was the incidence of further decompensation and the secondary outcome was overall survival.
In total, 3,949 individual patient data sets were extracted from 12 controlled studies and, after PS matching, 2,338 patients with similar characteristics (SOC = 1,749; TIPS = 589) were analysed. The 2-year cumulative incidence function of further decompensation in the PS-matched population was 0.48 (95% CI 0.43–0.52) in the TIPS group vs. 0.63 (95% CI 0.61–0.65) in the SOC group (stratified Gray’s test, p <0.0001), considering mortality and liver transplantation as competing events. The lower further decompensation rate with TIPS was confirmed by adjusted IPD meta-analysis (hazard ratio 0.44; 95% CI 0.37–0.54) and was consistent across TIPS indication subgroups. The 2-year cumulative survival probability was higher with TIPS than with SOC (0.71 vs. 0.63; p = 0.0001).
The use of TIPS for refractory ascites and for prevention of variceal rebleeding reduces the incidence of a further decompensation event compared with SOC and increases survival in highly selected patients.
A further decompensation (new or worsening ascites, variceal bleeding or rebleeding, hepatic encephalopathy, jaundice, hepatorenal syndrome–acute kidney injury and spontaneous bacterial peritonitis) in patients with cirrhosis is associated with a poor prognosis. Besides the known role of TIPS in portal hypertension-related complications, this study shows that TIPS is also able to decrease the overall risk of a further decompensation and increase survival compared with standard of care. These results further support the role of TIPS in the management of patients with cirrhosis and portal hypertension-related complications.
Nonlinear effects and effect modification at the participant-level in IPD meta-analysis part 2: methodological guidance is available
2023, Journal of Clinical Epidemiology
To review methodological guidance for nonlinear covariate-outcome associations (NL), and linear effect modification and nonlinear effect modification (LEM and NLEM) at the participant level in individual participant data meta-analyses (IPDMAs) and their power requirements.
We searched Medline, Embase, Web of Science, Scopus, PsycINFO and the Cochrane Library to identify methodology publications on IPDMA of LEM, NL or NLEM (PROSPERO CRD42019126768).
Through screening 6,466 records we identified 54 potential articles of which 23 full texts were relevant. Nine further relevant publications were published before or after the literature search and were added. Of these 32 references, 21 articles considered LEM, 6 articles NL or NLEM and 6 articles described sample size calculations. A book described all four. Sample size may be calculated through simulation or closed form. Assessments of LEM or NLEM at the participant level need to be based on within-trial information alone. Nonlinearity (NL or NLEM) can be modeled using polynomials or splines to avoid categorization.
Detailed methodological guidance on IPDMA of effect modification at participant-level is available. However, methodology papers for sample size and nonlinearity are rarer and may not cover all scenarios. On these aspects, further guidance is needed.
Nonlinear effects and effect modification at the participant-level in IPD meta-analysis part 1: analysis methods are often substandard
2023, Journal of Clinical Epidemiology
To review analysis methods used for linear effect modification (LEM), nonlinear covariate-outcome associations (NL) and nonlinear effect modification (NLEM) at the participant-level in individual participant data meta-analysis (IPDMA).
We searched Medline, Embase, Web of Science, Scopus, PsycINFO and the Cochrane Library to identify IPDMA of randomized controlled trials (PROSPERO CRD42019126768). We investigated if and how IPDMA examined LEM, NL and NLEM, including whether aggregation bias was addressed and if power was considered.
We screened 6,466 records, randomly sampled 207 and identified 100 IPDMA of LEM, NL or NLEM. Power for LEM was calculated a priori in 3 IPDMA. Of 100 IPDMA, 94 analyzed LEM, 4 NLEM and 8 NL. One-stage models were favoured for all three (56%, 100%, 50%, respectively). Two-stage models were used in 15%, 0% and 25% of IPDMA with unclear descriptions in 30%, 0% and 25%, respectively. Only 12% of one-stage LEM and NLEM IPDMA provided sufficient detail to confirm they had addressed aggregation bias.
Investigation of effect modification at the participant-level is common in IPDMA projects, but methods are often open to bias or lack detailed descriptions. Nonlinearity of continuous covariates and power of IPDMA are rarely assessed.
Sleep timing, chronotype, and posttraumatic stress disorder: An individual participant data meta-analysis
2023, Psychiatry Research
Sleep disturbance is a major component of posttraumatic stress disorder (PTSD). The role of circadian disruption is largely overlooked, though many PTSD studies collect proxy markers of circadian timing. This individual participant data (IPD) meta-analysis examined the correlation between sleep timing / chronotype and PTSD severity among individuals diagnosed with PTSD, the standardized mean difference in sleep timing / chronotype for individuals with and without PTSD, and moderators of these relationships. A systematic search was conducted; authors provided IPD for 27 studies and aggregate data for 16 studies (3,011 participants with PTSD; 2,703 participants without PTSD). Two-step meta-analyses were conducted using a random-effects multivariate approach with robust variance estimation. Bedtime and wake time were not significantly associated with PTSD symptoms or diagnosis. Less total sleep time / time in bed was weakly associated with greater PTSD symptoms. Moderator analyses revealed that effect sizes were stronger in certain populations and when using wrist actigraphy to measure sleep timing; however, gap maps revealed few studies in moderator categories with the strongest effects. Only two studies measured chronotype, prohibiting strong conclusions. Our findings indicate that the relationship between sleep timing and PTSD is weak; however, key gaps in the literature warrant further study.
Modernizing evidence synthesis for evidence-based medicine
2023, Clinical Decision Support and beyond: Progress and Opportunities in Knowledge-Enhanced Health and Healthcare
Due to the exponential expansion of the biomedical literature, systematic reviews and meta-analyses are crucial to evidence-based medicine. To answer a specific research question, a systematic review identifies, appraises, and synthesizes all practically-identifiable studies that fit pre-specified eligibility criteria. Meta-analysis refers to a set of statistical techniques for combining quantitative results from the studies included in a systematic review. This chapter provides a high-level introduction to the premise, uses, and steps of systematic reviews and meta-analyses. We also discuss how systematic reviews and meta-analyses can be accessed and the current and potential roles that they play in the evidence ecosystem. Throughout, we discuss the potential for medical informatics to improve the process of systematic reviews and meta-analysis.

View all citing articles on Scopus

View full text

ReviewA decade of individual participant data meta-analyses: A review of current practice

Abstract

Introduction

Methods

Results

Conclusion

Introduction

Section snippets

Methods

Results

Quality of reporting

Statistical methods

Discussion

Conclusion

Funding

Acknowledgements

Lancet

J. Am. Acad. Dermatol.

J. Am. Coll. Cardiol.

J. Am. Coll. Cardiol.

Lancet Oncol.

Blood

J. Am. Coll. Cardiol.

J. Am. Coll. Cardiol.

J. Nutr.

Lancet

J. Subst. Abus. Treat.

Am. Heart J.

J. Thromb. Haemost.

Dig. Liver Dis.

J. Am. Coll. Surg.

Lancet Infect. Dis.

Lancet Respir. Med.

Am. J. Cardiol.

J. Psychiatr. Res.

Ann. Oncol.

J. Am. Coll. Cardiol.

Eur. J. Cancer

Lancet Oncol.

To IPD or not to IPD?

Eval. Health Prof.

Practical methodology of meta-analyses (overviews) using updated individual patient data

Stat. Med.

Meta-analysis of individual patient data from randomized trials; a review of methods used in practice

Cinical Trials

Meta-analysis of continuous outcome data from individual patients

Stat. Med.

A multilevel model framework for meta-analysis of clinical trials with binary outcomes

Stat. Med.

Meta-analysis of ordinal outcomes using individual patient data

Stat. Med.

Meta-analysis of individual participant data: rationale, conduct, and reporting

BMJ

Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement

BMJ

Preferred reporting items for a systematic review and meta-analysis of individual participant data: the PRISMA-IPD statement

JAMA

Aspirin in the primary and secondary prevention of vascular disease: collaborative meta-analysis of individual participant data from randomised trials

Lancet

Meta-analysis of concomitant versus sequential radiochemotherapy in locally advanced non-small-cell lung cancer

J. Clin. Oncol.

Safety of pacemaker reuse: a meta-analysis with implications for underserved nations

Circ.

Monitoring initial response to angiotensin-converting enzyme inhibitor-based regimens: an individual patient data meta-analysis from randomized, placebo-controlled trials

Hypertension

Cognitive behavioral therapy age effects in child and adolescent anxiety: an individual patient data meta-analysis

Depress. Anxiety

High-dose chemotherapy with autologous stem-cell support as adjuvant therapy in breast cancer: overview of 15 randomized trials

J. Clin. Oncol.

Infant formula supplementation with long-chain polyunsaturated fatty acids has no effect on Bayley developmental scores at 18 months of age—IPD meta-analysis of 4 large clinical trials

J. Pediatr. Gastroenterol. Nutr.

Etanercept therapy in rheumatoid arthritis and the risk of malignancies: a systematic review and individual patient data meta-analysis of randomised controlled trials

Ann. Rheum. Dis.

Effect of amifostine on survival among patients treated with radiotherapy: a meta-analysis of individual patient data

J. Clin. Oncol.

Safety and tolerability of onabotulinumtoxinA in the treatment of facial lines: a meta-analysis of individual patient data from global clinical registration studies in 1678 participants

J. Am. Acad. Dermatol.

Clinical impact of thrombectomy in acute ST-elevation myocardial infarction: an individual patient-data pooled analysis of 11 trials

Eur. Heart J.

Systematic review of purine analog treatment for chronic lymphocytic leukemia: lessons for future trials

Review
A decade of individual participant data meta-analyses: A review of current practice