Table 3

Effect of covariates: betas (P-values) for significant covariates*

Covariates

Progression Measures

Age

Sex (1 = male, 0 = female)

Education

AMNART

Delusions

Hallucinations

Extra-pyramidal Signs

APOE Genotype

ADAS-Cog

-0.962 (.067)

NS

0.291 (.055)

-0.229 (<.001)

2.914 (.001)

NS

NS

NS

VSAT Time

-1.493 (<.001)

NS

NS

-2.339 (.001)

NS

NS

NS

NS

VSAT Errors

-0.179 (<.001)

NS

NS

-0.272 (<.001)

NS

NS

NS

NS

SCDR

NS

NS

NS

NS

1.386 (<.001)

1.245 (.003)

NS

NS

IADL

NS

-2.109 (<.001)

NS

NS

2.762 (<.001)

1.619 (.008)

NS

NS

PSMS

0.037 (.055)

NS

NS

NS

1.509 (<.001)

1.945 (.009)

NS

NS

*Betas calculated in models adjusted for baseline severity, duration, pre-progression rate × time, pre-progression × time squared (if applicable), and other covariates that achieved the selection criterion of P < 0.10. NS means the covariate did not achieve the criterion of P < .10, or did not retain this significance level when included in the full model.

ADAS-Cog = Alzheimer's disease Assessment Scale-Cognitive Subscale; AMNART = American version of the New Adult Reading Test; CDR-SB = Clinical Dementia Rating Scale Sum of Boxes; IADL = Instrumental Activities of Daily Living scale; PSMS = Physical Self-Maintenance Scale; VSAT = Verbal Series Attention Test.

Doody et al. Alzheimer's Research & Therapy 2010 2:2   doi:10.1186/alzrt25