The Development of a Revised Canadian Myalgic
Encephalomyelitis-Chronic Fatigue Syndrome Case Definition
http://www.scipub.org/fulltext/ajbb/ajbb62120-135.pdf
1Leonard A. Jason, 1Meredyth Evans, 1Nicole Porter, 1Molly Brown,
1Abigail Brown, 1Jessica Hunnell, 1Valerie Anderson, 1Athena Lerch,
2Kenny De Meirleir and 3Fred Friedberg
1Department of Psychology, DePaul University, Center for Community
Research, Chicago, Il, 60614, USA
2Department of Physical Education and Physical Therapy, Vrije
Universiteit Brussel, Belgium
3Department of Psychiatry and Behavioral Science, State University of
New York at Stony Brook, USA
Corresponding Author: Leonard A. Jason, Department of Psychology,
DePaul University, Center for Community Research,
Chicago, Il, 60614, USA Tel: 773-325-2018 Fax: 773-325-4923
American Journal of Biochemistry and Biotechnology 6 (2): 120-135, 2010
ISSN 1553-3468
2010 Science Publications
Abstract:
Problem statement: Several investigators have indicated that case
definitions for Chronic Fatigue Syndrome (CFS) are characterized by
vaguely worded criteria that lack operational definitions and
guidelines. The most widely used CFS case definition is the Fukuda et
al. criteria, which uses polythetic criteria (i.e., patients are only
required to have four out of a possible eight symptoms). Yet two of
these eight symptoms (post-exertional malaise and memory/concentration
problems) are an essential feature of this illness and the Fukuda et
al. criteria do not require that these symptoms be present among all
patients. Significant methodological problems could occur if
investigators in different settings recruit samples with different
percentages of these core symptoms. In contrast, the Canadian clinical
case definition does require specific ME/CFS symptoms such as
post-exertional malaise and memory/concentration problems. The
provision of operationally explicit, objective criteria on specific
key symptoms might reduce criterion variance as a source of
unreliability. In addition, the use of structured interview schedules
will ensure that symptoms are assessed in a consistent way across
settings.
Conclusion/Recommendations: In this article, we specified explicit
rules for determining whether critical symptoms meet ME/CFS criteria
using a revised Canadian case definition and a questionnaire has been
developed to assess core symptoms. It is hoped that these developments
will lead to increased reliability of this revised Canadian case
definition as well as more frequent use of these criteria by
investigators.