Evaluation of a screening questionnaire
for genetic studies of Parkinson's disease.
A screening questionnaire with high sensitivity for detection of
Parkinson's disease would make it easier to identify undiagnosed, yet
affected, family members for genetic research.
We assessed the validity of a screening questionnaire developed by Duarte
et al. [1995: Mov Disord 10:643-649] with reported high specificity and
sensitivity for Parkinson's disease (PD).
We applied the questionnaire to 78 asymptomatic members of families that
had at least two people diagnosed with PD.
These families were participating in a linkage study of Parkinson's disease.
Examination of these 78 revealed that 53 were normal (normal controls) and
25 were classified ("undiagnosed" PD defined) as possible, probable, or
clinically definite PD based on standardized criteria.
We compared these results with 123 patients with clinically definite PD
("diagnosed" PD).
There were significant differences among the mean scores on the
questionnaire for normal controls (4.4), subjects with undiagnosed PD
(9.8), and patients with diagnosed PD (42.1; p<0.000001) and a significant
difference between undiagnosed PD and normals (p<0.01).
The questionnaire had only 4% sensitivity for detection of parkinsonism in
undiagnosed PD using the original criteria [Duarte et al., 1995].
Revising the criteria increased the sensitivity from 4 to 48% in the
undiagnosed group.
The positive predictive value was 39% and the negative predictive value was
72%.
Prospective application of these revised criteria is necessary to confirm
the improved sensitivity.
However, we conclude that this screening questionnaire has inadequate
sensitivity for detection of mild parkinsonism and direct examination is
still critical for accurate classification for genetic studies.
Copyright 1999 Wiley-Liss, Inc.
Am J Med Genet 1999 Oct 15;88(5):539-543
Racette BA, Rundle M, Parsian A, Perlmutter JS
Washington University School of Medicine, St. Louis, Missouri, USA
PMID: 10490713
<http://www.ncbi.nlm.nih.gov/PubMed/>
janet paterson
52 now / 41 dx / 37 onset
613 256 8340 po box 171 almonte ontario canada K0A 1A0
a new voice: <http://www.geocities.com/SoHo/Village/6263/>
<[log in to unmask]>
