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Progress in Clinical Neurosciences: Measuring the Benefit of Therapies for Neurological Disorders

Published online by Cambridge University Press:  02 December 2014

Miguel Bussière  and
Samuel Wiebe
Miguel Bussière*
Affiliation:
Department of Clinical Neurological Sciences, University of Western Ontario, London, Ontario, Canada
Samuel Wiebe
Affiliation:
Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
*
Division of Neurology, Department of Clinical Neurological Sciences, University of Western Ontario, 339 Windermere Road, Rm 7-GE6, London, Ontario, N6A 5A5, Canada
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Abstract:

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Background:

Clinicians in the neurosciences need to interpret and apply a growing body of evidence about therapy.

Methods:

Using a clinical scenario about painful diabetic neuropathy and evidence about one treatment option, we review the advantages, limitations, and the clinical interpretation of commonly reported measures of effectiveness, emphasizing their application to the care of individual patients.

Results:

Absolute differences between treatment and control groups (e.g., absolute risk difference) are clinically intuitive and preferable to relative measures (e.g., relative risk). The number needed to treat is particularly useful and clinically applicable. Continuous measures are best interpreted using thresholds of clinically important change, which provide information about the number of patients experiencing meaningful improvement or worsening.

Conclusions:

Using simple principles of evidence based care, clinicians can correctly interpret the common measures of treatment effectiveness and apply them to the care of individual patients.

Résumé:

RÉSUMÉ: Introduction:

Les cliniciens en neurosciences doivent interpréter et appliquer de plus en plus de données sur le traitement des maladies neurologiques.

Méthodes:

Au moyen d’un scénario clinique décrivant une neuropathie diabétique douloureuse et des données sur une option thérapeutique, nous avons revu les avantages, les limites et l’interprétation clinique de mesures d’efficacité fréquemment rapportées, en mettant l’accent sur leur application au traitement de patients individuels.

Résultats:

Les différences absolues entre le groupe sous traitement et le groupe témoin (e.g. la différence absolue du risque) sont intuitives en clinique et préférables à des mesures relatives (e.g. le risque relatif). Le nombre de sujets à traiter (NNT) est particulièrement utile et il est applicable en clinique. La meilleure interprétation de mesures continues est l’utilisation de seuils de changements importants en clinique qui donnent de l’information sur le nombre de patients dont l’état s’améliore ou empire de façon significative.

Conclusions:

En utilisant des principes simples de thérapie factuelle, les cliniciens peuvent interpréter correctement les mesures courantes d’efficacité thérapeutique et les appliquer aux soins de patients particuliers.

Type
Review Article
Information
Canadian Journal of Neurological Sciences , Volume 32 , Issue 4 , November 2005 , pp. 419 - 424
Copyright
Copyright © The Canadian Journal of Neurological 2005

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