Table 1.
Descriptive statistics for the entire sample
| Number | (%) | |
|---|---|---|
| N | 689 | |
| Female sex | 529 | (76.8 %) |
| White race | 643 | (93.3 %) |
| Mean | (SD) | Range | |
|---|---|---|---|
| Age | 81.75 | (7.63) | 59.58 to 100.78 |
| Education | 15.17 | (3.05) | 0 to 28 |
| WMS-R Logical Memory—immediate recall Ia raw score | 12.54 | (4.41) | 0 to 24 |
| WMS-R Logical Memory—delayed recall IIa raw score | 10.98 | (4.81) | 0 to 23 |
| CERAD Word List Memory, trials 1–3, immediate recall raw score | 18.65 | (4.55) | 7 to 30 |
| CERAD Word List Memory, trials 1–3, delayed recall raw score | 5.85 | (2.42) | 0 to 10 |
| CERAD Word List Memory, trials 1–3, recognition memory raw score | 9.63 | (0.96) | 0 to 10 |
| East Boston Memory Test immediate recall raw score | 9.81 | (1.92) | 0 to 12 |
| East Boston Memory Test delayed recall raw score | 9.39 | (2.31) | 0 to 12 |
| Boston Naming Test raw score | 14.10 | (1.12) | 8 to 15 |
| Verbal Semantic Fluency raw score | 35.28 | (9.49) | 7 to 70 |
| NART Word Reading raw score | 12.79 | (2.68) | 1 to 15 |
| Digit Span FORWARD raw score | 8.29 | (1.97) | 2 to 12 |
| Digit Span backward raw score | 6.34 | (1.90) | 1 to 12 |
| Digit Ordering raw score | 7.37 | (1.57) | 2 to 13 |
| Symbol Digit raw score | 40.04 | (10.12) | 8 to 77 |
| Number Comparison raw score | 25.15 | (7.11) | 0 to 48 |
| Stroop Color Naming raw score | 19.69 | (7.54) | 0 to 45 |
| Stroop Word Reading raw score | 48.16 | (13.68) | 0 to 80 |
| Judgment of Line Orientation raw score | 10.31 | (3.04) | 0 to 15 |
| Progressive Matrices raw score | 10.52 | (1.83) | 0 to 12 |
| Global Cognition z score | 0.25 | (0.51) | −1.42 to 1.59 |
| Total decision-making raw score | 7.69 | (2.80) | 0 to 12 |
| Income when enrolled | 7.19 | (2.44) | 1 to 10 |
| Depression | 0.94 | (1.53) | 0 to 9 |
| Impulsivity mean | 13.48 | (4.46) | 0 to 28 |
| Risk aversion (gamma) | 0.32 | (0.30) | 0.06 to 0.91 |
| Temporal discounting (alpha) | 0.66 | (0.81) | 0.07 to 2.76 |
WMS-R Logical Memory—immediate recall Ia and delayed recall IIa have a possible range of 0–25; CERAD Word List Memory, trials 1–3, immediate recall has a possible range of 0–30; CERAD Word List Memory, trials 1–3, delayed recall has a possible range of 0–10; CERAD word List Memory, trials 1–3, Recognition Memory has a possible range of 0–10; East Boston Memory Test Immediate Recall and Delayed Recall have a possible range of 0–12; Boston Naming Test has a possible range of 0–15; Verbal Semantic Fluency has a possible range of 0–75; NART Word Reading has a possible range of 0–15; Digit Span forward and Digit Span backward have a possible range of 0–12; digit ordering has a possible range of 0–14; Symbol Digit has a possible range of 0–110; Number Comparison has a range of 0–48; Stroop Color Naming and Stroop Word Reading have a possible range of 0–100; Judgment Of Line Orientation has a possible range of 0–15; Progressive Matrices has a possible range of 0–16; Total decision making has a possible range of 0–12; depression measured by 10-item CES-D sum, impulsivity measured by 8 questions from the NEO Personality Inventory-Revised, income categories: (1) USD 0–4,999, (2) USD 5,000–9,999, (3) USD 10,000–14,999, (4) USD 15,000–19,999, (5) USD 20,000–24,999, (6) USD 25,000–29,999, (7) USD 30,000–34,999, (8) USD 35,000–49,999, (9) USD 50,000–74,999, (10) USD >75,000. Only 2 people had a level of education of less than 9 years
N sample size, SD standard deviation, WMS-R Wechsler Memory Scale-Revised, CERAD Consortium to Establish a Registry for Alzheimer’s Disease, NART National Adult Reading Test