TY  - THES
AB  - Neuropsychological tests are essential for assessing cognitive function, but floor and ceiling effects, summary score limitations, and longitudinal censoring reduce accuracy. This thesis applies censored normal (Type 1 Tobit) models to longitudinal data from the Boston Naming Test (ceiling effects) and Word List Delayed Recall (floor effects). Simulations show that ignoring these effects misestimates change points and population trends. Tobit models improved classification of Mild Cognitive Impairment and score prediction compared to standard models, with higher ROC values and lower mean squared error. Accounting for ceiling and floor effects enhances cognitive decline detection and supports earlier intervention strategies.
AD  - Oregon Health and Science University
AU  - Perkins, Jedediah
DA  - 2011
DO  - 10.6083/M4FJ2DSD
DO  - DOI
ED  - Pavel, Misha
ED  - Advisor
ID  - 721
KW  - Neuropsychological Tests
KW  - Longitudinal Studies
KW  - Cognitive Dysfunction
KW  - mild cognitive impairment
KW  - longitudinal method
L1  - https://digitalcollections.ohsu.edu/record/721/files/724_etd.pdf
L2  - https://digitalcollections.ohsu.edu/record/721/files/724_etd.pdf
L4  - https://digitalcollections.ohsu.edu/record/721/files/724_etd.pdf
LK  - https://digitalcollections.ohsu.edu/record/721/files/724_etd.pdf
N2  - Neuropsychological tests are essential for assessing cognitive function, but floor and ceiling effects, summary score limitations, and longitudinal censoring reduce accuracy. This thesis applies censored normal (Type 1 Tobit) models to longitudinal data from the Boston Naming Test (ceiling effects) and Word List Delayed Recall (floor effects). Simulations show that ignoring these effects misestimates change points and population trends. Tobit models improved classification of Mild Cognitive Impairment and score prediction compared to standard models, with higher ROC values and lower mean squared error. Accounting for ceiling and floor effects enhances cognitive decline detection and supports earlier intervention strategies.
PB  - Oregon Health and Science University
PY  - 2011
T1  - Censored data models for longitudinal neuropsychological score analysis
TI  - Censored data models for longitudinal neuropsychological score analysis
UR  - https://digitalcollections.ohsu.edu/record/721/files/724_etd.pdf
Y1  - 2011
ER  -