Article Figures & Data
Figures
- Figure 1.
Estimated marginal probabilities of education ≤12 years for MoCA items significantly associated with formal education. Abbreviations: MoCA, Montreal Cognitive Assessment.
Tables
Fixed Effects Coefficient SE Z P 95% CI Intercept −1.179 0.27 −4.40 0.000 −2.04 −0.33 Age 0.052 0.01 4.96 0.000 0.03 0.07 Male 0.292 0.13 2.27 0.023 0.04 0.55 Adjusted GDS 0.082 0.04 2.01 0.045 0.00 0.16 Has SMC 0.196 0.18 1.12 0.264 −0.15 0.54 History of HTN 0.585 0.13 4.54 0.000 0.33 0.84 Elevated Aβ 0.391 0.15 2.53 0.011 0.09 0.69 ≤12 years education 0.577 0.20 2.89 0.004 0.18 0.97 Random Effects SD χ² P 95% CI Site within study 0.475 52.74 <.001 0.30, 0.69 Study 0.325 6.88 0.009 0.10, 1.46 Abbreviations: GDS, Geriatric Depression Scale; GLMM, generalized linear mixed model; HTN, hypertension; SMC, subjective memory complaint; SD, standard deviation; SE, standard error; CI, confidence interval; MoCA, Montreal Cognitive Assessment.
Notes: Model coefficients are in log odds. 95% CIs for model coefficients are in log odds. Age and adjusted GDS centered at respective means. Study is either ADNI or NACC.
Table 1. Participant Characteristics
High School or Less More than High School MCI Continuous Variables Mean SD Mean SD d 95% CI Mean SD Age 71.54 6.24 72.18 6.33 0.17 (−0.07, 0.28) 73.05 7.27 Medication count 8.07 4.91 7.27 4.51 0.16 (−0.01, 0.36) 7.90 4.55 Adjusted GDS 1.09 1.88 0.87 1.48 0.14 (−0.04, 0.32) 1.62 2.04 Discrete Variables n % n % V 95% CI n % Female 92 0.66 678 0.57 0.05 (0.00, 0.11) 534 0.43 White 105 0.76 1043 0.879 0.14 (0.09, 0.20) 1144 0.92 Elevated brain Aβ 24 0.17 245 0.21 0.00 (0.00, 0.08) 626 0.50 History of HTN 78 0.56 487 0.41 0.09 (0.04, 0.15) 636 0.51 Has SMC 17 0.12 183 0.15 0.00 (0.00, 0.08) 554 0.45 In ADNI 48 0.35 437 0.37 0.00 (0.00, 0.07) 568 0.46 Abbreviations: ADNI, Alzheimer's Disease Neuroimaging Initiative; GDS, Geriatric Depression Scale; HTN, hypertension; MoCA, Montreal Cognitive Assessment; SMC, Subjective Memory Complaint; SD, standard deviation; SE, standard error; CI, confidence interval; V, Cramer’s V – measure of association between two nominal variables; d, Cohen’s d -- an effect size used to indicate the standardised difference between two means; MCI, mild cognitive impairment.
Notes: Continuous variables compared between education groups using t test with Cohen's d for effect size. Discrete variables compared between education groups using chi-square tests with Cramer's V, with bias correction, for effect size. 95% CIs are for effect size. Bolded effect size values are significant at P < .05 level.
- Table 3.
MoCA Items That Are Significant Predictors of Lower Education in a Backwards Selection Binomial GLMM
Fixed Effects Coefficient SE Z P 95% CI Intercept −1.262 0.25 −5.03 0.000 −1.78 −0.78 Cube copy correct −0.581 0.22 −2.67 0.008 −1.01 −0.15 Serial subtraction score −0.469 0.19 −2.50 0.013 −0.83 −0.09 ≥11 F words −0.800 0.24 −3.36 0.001 −1.26 −0.32 Abstraction score −0.801 0.17 −4.64 <.001 −1.14 −0.46 Random Effects SD χ² P 95% CI Study Site 0.475 3.027 0.08 0 0.894 Abbreviations: GLMM, generalized linear mixed model; SD, standard deviation; SE, standard error; CI, confidence interval; MoCA, Montreal Cognitive Assessment.
Note: Model coefficients are in log odds. 95% CIs for model coefficients are in log odds. Serial subtraction and abstraction scores centered at means. There was zero variance for study (i.e., ADNI or NACC) in model; it was excluded as a random effect because the model only converged after it was removed.
Fixed Effects Coefficient SE t P 95% CI Intercept −0.111 0.167 −0.667 0.505 −0.439 0.216 Age −0.003 0.009 −0.288 0.774 −0.020 0.015 Male 0.370 0.114 3.250 0.001 0.147 0.593 Adjusted GDS 0.130 0.034 3.872 <.001 0.064 0.196 Has SMC 1.682 0.127 13.272 <.001 1.434 1.930 History of HTN −0.009 0.116 −0.077 0.938 −0.237 0.219 Elevated Aβ 1.114 0.124 9.007 <.001 0.872 1.357 ≤12 years education 0.322 0.177 1.823 0.068 −0.024 0.669 Alternative MoCA score −0.475 0.028 −17.092 <.001 −0.529 −0.420 Random Effects SD χ² P 95% CI Site within study 0.905 170.09 <.001 0.724 1.128 Abbreviations: GDS, Geriatric Depression Scale; GLMM, generalized linear mixed model; HTN, hypertension; SMC, subjective memory complaint; SD, standard deviation; CI, confidence interval; MCI, mild cognitive impairment; MoCA, Montreal Cognitive Assessment.
Note: Model coefficients are in log odds. 95% CIs for model coefficients are in log odds. Serial subtraction and abstraction scores centered at means. There was zero variance for study (i.e., ADNI or NACC) in model; it was excluded as a random effect because the model only converged after it was removed.
Fixed Effects Coefficient SE t P 95% CI Intercept −1.076 0.33 −3.23 .001 −1.73, −0.42 Age 0.050 0.01 4.75 <.001 0.03, 0.07 Male 0.571 0.13 4.45 <.001 0.32, 0.82 Adjusted GDS 0.079 0.04 1.92 .054 0.00, 0.16 Has SMC 0.133 0.18 0.76 .450 −0.21, 0.48 History of HTN 0.514 0.13 3.97 <.001 0.26, 0.77 Elevated Aβ 0.152 0.16 0.97 .333 −0.16, 0.46 12 Years Education 0.088 0.21 0.43 .671 −0.32, 0.49 Random Effects SD χ² P 95% CI Site within study 0.491 39.04 <.001 0.31, 0.71 Study 0.429 22.98 <.001 0.17, 1.88 Abbreviations: GDS, Geriatric Depression Scale; GLMM, generalized linear mixed model; HTN, hypertension; SMC, subjective memory complaint; SD, standard deviation; CI, confidence interval; MoCA, Montreal Cognitive Assessment.
Notes: Model coefficients are in log odds. 95% CIs for model coefficients are in log odds. Age and adjusted GDS centered at respective means. Study is either ADNI or NACC.
