I. Litvan et al., VALIDITY AND RELIABILITY OF THE PRELIMINARY NINDS NEUROPATHOLOGIC CRITERIA FOR PROGRESSIVE SUPRANUCLEAR PALSY AND RELATED DISORDERS, Journal of neuropathology and experimental neurology, 55(1), 1996, pp. 97-105
We investigated the validity and reliability of diagnoses made by eigh
t neuropathologists who used the preliminary NINDS neuropathologic dia
gnostic criteria for progressive supranuclear palsy (PSP) and related
disorders. The specific disorders were typical, atypical, and combined
PSP, postencephalitic parkinsonism, corticobasal ganglionic degenerat
ion, and Pick's disease. These disorders were chosen because of the di
fficulties in their neuropathologic differentiation. We assessed valid
ity by measuring sensitivity and positive predictive value. Reliabilit
y was evaluated by measuring pairwise and group agreement. From a tota
l of 62 histologic cases, each neuropathologist independently classifi
ed 16 to 19 cases for the pairwise analysis and 5 to 6 cases for the g
roup analysis. The neuropathologists were unaware of the study design,
unfamiliar with the assigned cases, and initially had no clinical inf
ormation about the cases. Our results showed that with routine samplin
g and staining methods, neuropathologic examination alone was not full
y adequate for differentiating the disorders. The main difficulties we
re discriminating the subtypes of PSP and separating postencephalitic
parkinsonism from PSP. Corticobasal ganglionic degeneration and Pick's
disease were less difficult to distinguish from PSP. The addition of
minimal clinical information contributed to the accuracy of the diagno
sis. On the basis of results obtained, we propose clinicopathologic di
agnostic criteria to improve on the NINDS criteria.