Funded PhD Studentship in Evidence Synthesis ... - University of York

properties of the methods using Monte Carlo (simulation) studies; (iv) investigate thepractical implications of choosing different methods in practical applications; and (v) preparerecommendations on the most appropriate method(s) to consider for widespread applicationof random-effects meta-analysis.Further reading:DerSimonian R, Laird N. Meta-analysis in clinical trials, Controlled Clinical Trials 1986; 7;177–188; doi: 10.1016/0197-2456(86)90046-2.Higgins JPT, Thompson SG, Spiegelhalter DJ. A re-evaluation of random-effects metaanalysis.Journal of the Royal Statistical Society Series A 2009; 172: 137-159; doi:10.1111/j.1467-985X.2008.00552.x.DerSimonian R, Kacker R. Random-effects model for meta-analysis of clinical trials: Anupdate. Contemporary Clinical Trials 2007; 28: 105–114; doi:10.1016/j.cct.2006.04.004.Dealing with diverse covariates in meta-analysis of observational studiesPotential supervisors: Julian Higgins, Mark Simmonds, Lesley StewartCollaborators: Bob PhillipsA common problem in meta-analysis of observational studies is that different studies includedifferent covariates in the regression models they use to analyse the data. For example, inmeta-analysis of non-randomized studies of interventions, or in meta-analysis of exposurediseaserelationships in epidemiology, different sets of potential confounders may have been‘adjusted for’ in an attempt to reduce bias. In meta-analyses of risk prediction models,different sets of predictors may have been included in the model. Estimates of regressioncoefficients from models with different covariates estimate different parameters. Suchdifferences may or may not be important, depending on the magnitude of the relationshipsamong the variables. Some methods have been proposed for handling these situations. Forexample, given the individual participant data, multivariate meta-analysis can be used tomodel coefficients that are adjusted in different ways [FSC 2009]. Alternatively, Bayesianapproaches for accounting for unmeasured confounders can be used [McCandless 2012].However, there is a need for further consideration and development in this area.This project will explore statistical methods for synthesizing results from regression modelswhen different sets of covariates have been included in the models used by different studies.Methods applicable to both individual participant data and aggregate (e.g. published) resultswill be explored.Further reading:The Fibrinogen Studies Collaboration (Writing committee: D Jackson and I White).Systematically missing confounders in individual participant data meta-analysis ofobservational cohort studies. Statistics in Medicine 2009; 28: 1218-1237. doi:10.1002/sim.3540.McCandless LC. Meta-analysis of observational studies with unmeasured confounders. TheInternational Journal of Biostatistics 2012; 8: 1–31. doi: 10.2202/1557-4679.1350.

Person SpecificationAttributes Essential DesirableQualificationsDegree in a health, health services research, statisticalor science topic. Minimum upper second class.KnowledgeEvidence synthesis including methods of data synthesisappropriate to chosen area of studyUnderstanding of the health fieldUnderstanding of and familiarity with statisticalpackagesPersonal AttributesAnalytical thinker with good problem solving abilities.Ability to both ‘think outside of the box’ and bepragmatic in approach.Self-motivation, excellent organisational skills and acommitment to the delivery of high quality outputs.Excellent written and verbal communication and interpersonalskillsAbility to work collaboratively.

Process for applicationClosing date for applications is 9 th July 2012Applications should be made using the Department of Health Sciences on-line applicationprocess which can be accessed using the following link.http://www.york.ac.uk/admin/uao/ugrad/courses/cupid/index.cfm?ippCode=DRPHSCSHSC3&level=postgraduate.Applicants should state that they are applying for the advertised CRD studentship inEvidence Synthesis and provide a curriculum vitae and two academic references. Youshould also upload an outline of your intended area of research, stating potential methods orapproaches to be adopted, and set in the context of how it will contribute to developingevidence synthesis methods and/or contribute to better health decision making (up to 500words in PDF format). If you have already published academic papers, one of these mayalso be uploaded.InterviewsInterviews are likely to take place during the week beginning 23 rd July 2012. At interviewcandidates will be expected to give a short presentation on a project or piece of researchthat they have undertaken previously and outline their plans for developing a suitableproject.Informal EnquiriesProspective applicants who wish to discuss the studentships should contact Annie Christie,the Centre Administrator who will arrange a time to talk with potential supervisors. (01904321059, email: annie.christie@york.ac.uk).