Table 1.
Descriptive statistics: Cognitive tests and metabolite concentrations
| Mean | Standard Deviation | Minimum | Maximum | N <25% | |
|---|---|---|---|---|---|
| Age (years) | 22.14 | 3.15 | 18.50 | 30.00 | |
| Education (years) | 15.62 | 1.36 | 13.60 | 18.00 | |
| WID | 102.32 | 12.14 | 76 | 125 | 6 |
| TOWRE – SWE | 91.68 | 12.32 | 62 | 104 | 12 |
| WAT | 95.90 | 13.22 | 65 | 119 | 10 |
| TOWRE – PD | 45.76 | 13.97 | 13 | 61 | 13 |
| ND Comprehension | 15.71 | 3.81 | 4.10 | 18.90 | 7 |
| General cognitive ability | 108.85 | 8.18 | 92 | 123 | 0 |
| Cho/Cr | 0.75 | 0.10 | 0.60 | 1.01 | |
| NAA/Cr | 2.01 | 0.31 | 1.31 | 2.65 | |
| mIns/Cr | 0.55 | 0.19 | 0.31 | 1.17 | |
| Grey Matter/White Matter | 0.75 | 0.28 | 0.32 | 1.39 | |
N < 25% = number of indiviudals scoring less than or equal to the 25th percentile on the measure. ND Comprehension = Grade equivalency score on the Nelson-Denny Test of Reading Comprehension [For the Nelson Denny test percentile scores were not available therefore the number in the N< 25% column is the number of individuals whose grade equivalency score was 3 or more uyears below their level of education], TOWRE – PDE = Test of word reading efficiency – phonemic decoding efficiency subtest; TOWRE – SWE = Test of word reading efficiency – sight efficiency subtest. For both versions of the TOWRE raw scores are reported because standardized scores were not available for our entire sample. WID (Word Identification), WAT (Word Attack), and cognitive ability estimate are from the WJ-III and standard scores are reported. Cho/cr = ratio of choling/creatine; mIns/Cr = ratio of myoinositol/creatine; Naa/Cr = ratio of N-acetyl aspertate/creatine concentrations.