OBJECTIVE: To use values of cerebrospinal fluid tau and b-amyloid obtained from 2 different analytical immunoassays to differentiate @entity195 ( @entity195 ) from @entity747 ( @entity747 ). DESIGN: Cerebrospinal fluid values of total tau (T-tau) and b-amyloid 1-42 (Ab 1-42) obtained using the Innotest enzyme-linked immunosorbent assay were transformed using a linear regression model to equivalent values obtained using the INNO-BIA AlzBio3 (xMAP; Luminex) assay. Cutoff values obtained from the xMAP assay were developed in a series of autopsy-confirmed cases and cross validated in another series of autopsy-confirmed samples using transformed enzyme-linked immunosorbent assay values to assess sensitivity and specificity for differentiating @entity195 from @entity747 . SETTING: @entity2414 clinics and neuropathologic and biomarker core centers. @entity1 : Seventy-five samples from @entity1 with cerebrospinal fluid data obtained from both assays were used for transformation of enzyme-linked immunosorbent assay values. Forty autopsy-confirmed cases (30 with @entity195 and 10 with @entity747 ) were used to establish diagnostic cutoff values and then cross validated in a second sample set of 21 autopsy-confirmed cases (11 with @entity195 and 10 with @entity747 ) with transformed enzyme-linked immunosorbent assay values. MAIN OUTCOME MEASURE: Diagnostic accuracy using transformed biomarker values. RESULTS: Data obtained from both assays were highly correlated. The T-tau to Ab 1-42 ratio had the highest correlation between measures (r = 0.928, P < .001) and high reliability of transformation (intraclass correlation coefficient= 0.89). A cutoff of 0.34 for the T-tau to Ab 1-42 ratio had 90% and 100% sensitivity and 96.7% and 91% specificity to differentiate @entity747 cases in the validation and cross-validation samples, respectively. CONCLUSIONS: Values from 2 analytical platforms can be transformed into equivalent units, which can distinguish @entity195 from @entity747 more accurately than the clinical diagnosis.

Comparison of cerebrospinal fluid levels of tau and Ab 1-42 in XXXX and frontotemporal degeneration using 2 analytical platforms.

@entity1 :: ('9606', 'Species') :: ['patients', 'PARTICIPANTS'] @entity2414 :: ('MESH:D008569', 'Disease') :: ['Tertiary memory disorder'] @entity747 :: ('MESH:D057174', 'Disease') :: ['frontotemporal lobar degeneration', 'FTLD'] @entity195 :: ('MESH:D000544', 'Disease') :: ['AD', 'Alzheimer disease']
@entity195 :: (MESH:D000544,Disease) :: ['Alzheimer disease']
