Please use this identifier to cite or link to this item:
DC FieldValue
dc.titleAnalysis and design of randomised clinical trials involving competing risks endpoints
dc.contributor.authorTai, B.-C.
dc.contributor.authorWee, J.
dc.contributor.authorMachin, D.
dc.identifier.citationTai, B.-C., Wee, J., Machin, D. (2011-05-19). Analysis and design of randomised clinical trials involving competing risks endpoints. Trials 12 : -. ScholarBank@NUS Repository.
dc.description.abstractBackground: In randomised clinical trials involving time-to-event outcomes, the failures concerned may be events of an entirely different nature and as such define a classical competing risks framework. In designing and analysing clinical trials involving such endpoints, it is important to account for the competing events, and evaluate how each contributes to the overall failure. An appropriate choice of statistical model is important for adequate determination of sample size.Methods: We describe how competing events may be summarised in such trials using cumulative incidence functions and Gray's test. The statistical modelling of competing events using proportional cause-specific and subdistribution hazard functions, and the corresponding procedures for sample size estimation are outlined. These are illustrated using data from a randomised clinical trial (SQNP01) of patients with advanced (non-metastatic) nasopharyngeal cancer.Results: In this trial, treatment has no effect on the competing event of loco-regional recurrence. Thus the effects of treatment on the hazard of distant metastasis were similar via both the cause-specific (unadjusted csHR = 0.43, 95% CI 0.25 - 0.72) and subdistribution (unadjusted subHR 0.43; 95% CI 0.25 - 0.76) hazard analyses, in favour of concurrent chemo-radiotherapy followed by adjuvant chemotherapy. Adjusting for nodal status and tumour size did not alter the results. The results of the logrank test (p = 0.002) comparing the cause-specific hazards and the Gray's test (p = 0.003) comparing the cumulative incidences also led to the same conclusion. However, the subdistribution hazard analysis requires many more subjects than the cause-specific hazard analysis to detect the same magnitude of effect.Conclusions: The cause-specific hazard analysis is appropriate for analysing competing risks outcomes when treatment has no effect on the cause-specific hazard of the competing event. It requires fewer subjects than the subdistribution hazard analysis for a similar effect size. However, if the main and competing events are influenced in opposing directions by an intervention, a subdistribution hazard analysis may be warranted. © 2011 Tai et al; licensee BioMed Central Ltd.
dc.contributor.departmentEPIDEMIOLOGY & PUBLIC HEALTH
Appears in Collections:Staff Publications

Show simple item record
Files in This Item:
File Description SizeFormatAccess SettingsVersion 
2011-analysis_design_randomised_clinical_trials-published.pdf388.77 kBAdobe PDF



Google ScholarTM



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.