Practice Parameter: Diagnostic assessment of the child with cerebral palsy
M.A.Whelan, MD, PhD, Neurologist, 122 Sugar Hill Road, Cooperstown, New York 13326mawhelan@capital.net
Submitted June 19, 2004
The recent Practice Parameter on the diagnostic assessment of the
child with cerebral palsy [1] presents findings and recommendations based
upon a re-working of the usual standards of classification of evidence.
The reclassification appears to have been undertaken to fortify the
strength of the presented studies. Thus, articles formerly classified as
Class III or IV, according to the usual AAN criteria, are now presented as
Class I evidence (authors' references 6, 7, 8, 15,16).
However, the studies remain what they are - studies of
selected, not representative, groups of patients. Figures for the
percentages of abnormalities found on imaging studies, and of the co-
morbidity of epilepsy, are unduly inflated as a result. Some co-
morbidities, such as visual impairment (which relies on a definition of
legal blindness not specified in the text) may be under-estimated.
Internally, there are also inconsistent classifications - a
studied classified as Class III in Table 3 is promoted to Class II in the
text (authors' reference 10), and studies identified as Class I are mis-
matched to both old and new definitions of this evidence (authors'
references 6,7,8,15,16,39,47). One study is actually a review
article (authors' reference 47).
The re-worked classification scheme is also intrinsically
unsatisfactory. The idea of a classification "appropriate only when the
diagnostic accuracy of the fact or intervention is known to be good" does
not stand up to scrutiny, nor do the artifices of the revised definitions
of "population" or "statistical".
Current pre-publication review processes continue to need
improvement, and systematic and authoritative statistical and
epidemiological consultation should be an intrinsic part of the generation
of parameters.
References
1. Ashwal S, Russman B.S., Blasco P.A. et al. Practice
Parameter: Diagnostic assessment of the child with cerebral palsy.
Neurology 2004;62:851-862.
The recent Practice Parameter on the diagnostic assessment of the child with cerebral palsy [1] presents findings and recommendations based upon a re-working of the usual standards of classification of evidence. The reclassification appears to have been undertaken to fortify the strength of the presented studies. Thus, articles formerly classified as Class III or IV, according to the usual AAN criteria, are now presented as Class I evidence (authors' references 6, 7, 8, 15,16).
However, the studies remain what they are - studies of selected, not representative, groups of patients. Figures for the percentages of abnormalities found on imaging studies, and of the co- morbidity of epilepsy, are unduly inflated as a result. Some co- morbidities, such as visual impairment (which relies on a definition of legal blindness not specified in the text) may be under-estimated.
Internally, there are also inconsistent classifications - a studied classified as Class III in Table 3 is promoted to Class II in the text (authors' reference 10), and studies identified as Class I are mis- matched to both old and new definitions of this evidence (authors' references 6,7,8,15,16,39,47). One study is actually a review article (authors' reference 47).
The re-worked classification scheme is also intrinsically unsatisfactory. The idea of a classification "appropriate only when the diagnostic accuracy of the fact or intervention is known to be good" does not stand up to scrutiny, nor do the artifices of the revised definitions of "population" or "statistical".
Current pre-publication review processes continue to need improvement, and systematic and authoritative statistical and epidemiological consultation should be an intrinsic part of the generation of parameters.
References
1. Ashwal S, Russman B.S., Blasco P.A. et al. Practice Parameter: Diagnostic assessment of the child with cerebral palsy. Neurology 2004;62:851-862.