Williamson, Paula R.; Smith, Catrin Tudur; Sander, Josemir W. and Marson, Anthony G. (2007) Importance of competing risks in the analysis of anti-epileptic drug failure. Trials, 8 . Article Number: 12. ISSN 1745-6215
Available under License Creative Commons Attribution.
Cited 2 times in WoS
Background: Retention time (time to treatment failure) is a commonly used outcome in antiepileptic drug (AED) studies. Methods: Two datasets are used to demonstrate the issues in a competing risks analysis of AEDs. First, data collection and follow-up considerations are discussed with reference to information from 15 monotherapy trials. Recommendations for improved data collection and cumulative incidence analysis are then illustrated using the SANAD trial dataset. The results are compared to the more common approach using standard survival analysis methods. Results: A non-significant difference in overall treatment failure time between gabapentin and topiramate (logrank test statistic = 0.01, 1 degree of freedom, p-value = 0.91) masked highly significant differences in opposite directions with gabapentin resulting in fewer withdrawals due to side effects (Gray's test statistic = 11.60, 1 degree of freedom, p = 0.0007) but more due to poor seizure control (Gray's test statistic = 14.47, 1 degree of freedom, p-value = 0.0001). The significant difference in overall treatment failure time between lamotrigine and carbamazepine (logrank test statistic = 5.6, 1 degree of freedom, p-value = 0.018) was due entirely to a significant benefit of lamotrigine in terms of side effects (Gray's test statistic = 10.27, 1 degree of freedom, p = 0.001). Conclusion: Treatment failure time can be measured reliably but care is needed to collect sufficient information on reasons for drug withdrawal to allow a competing risks analysis. Important differences between the profiles of AEDs may be missed unless appropriate statistical methods are used to fully investigate treatment failure time. Cumulative incidence analysis allows comparison of the probability of failure between two AEDs and is likely to be a more powerful approach than logrank analysis for most comparisons of standard and new anti-epileptic drugs.
|Additional Information:||Published: 29 March 2007. 10 pages (page numbers not for citation purposes).|
|Uncontrolled Keywords:||TONIC CLONIC SEIZURES; COMPARATIVE MONOTHERAPY TRIAL; MULTICENTER COMPARATIVE TRIAL; CONTROLLED CLINICAL-TRIAL; NEWLY-DIAGNOSED EPILEPSY; LONG-TERM RETENTION; SODIUM VALPROATE; DOUBLE-BLIND; ONSET EPILEPSY; CARBAMAZEPINE|
|Subjects:||R Medicine > RC Internal medicine > RC0321 Neuroscience. Biological psychiatry. Neuropsychiatry|
|Departments, Research Centres and Related Units:||Academic Faculties, Institutes and Research Centres > Faculty of Medicine > School of Clinical Sciences|
Academic Faculties, Institutes and Research Centres > Research Centres > Medical Statistics and Health Evaluation, Centre for
|Publisher's Statement:||© 2007 Williamson et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.|
|Deposited On:||27 Jun 2008 13:59|
|Last Modified:||24 Apr 2012 09:47|
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