Table 2.
Descriptive Statistics on Math Difficulty and Control Groups.
| MD (n = 83) |
No LD (n = 61) |
||||
|---|---|---|---|---|---|
| Variable | Category or Scale | M | SD | M | SD |
| Age | Years | 9.75 | 0.82 | 9.25 | 0.71 |
| Sex | Female (%) | 47.0 | 52.5 | ||
| Ethnicity | African American (%) | 52.4 | 52.5 | ||
| Caucasian (%) | 15.9 | 18.0 | |||
| Hispanic (%) | 25.6 | 26.2 | |||
| Other (%) | 6.1 | 3.3 | |||
| Reduced or free lunch | Received total (%) | 75.68 | 51.79 | ||
| WASI FSIQ | Standard score | 89.77 | 9.4 | 101.87 | 10.7 |
| WRAT-3 Arithmetic | Standard score | 86.77 | 4.6 | 109.89 | 7.7 |
| WRAT-3 Reading | Standard score | 91.37 | 12.5 | 108.23 | 8.2 |
| WJ-III Math Fluency | Standard score | 88.45 | 12.4 | 102.39 | 10.6 |
| SWAN-IV Inattention | –27 to +27 | –6.29 | 9.9 | +4.49 | 13.4 |
| Visual WM | Raw score | 7.94 | 2.4 | 9.56 | 3.6 |
| Verbal WM | Raw score | 6.33 | 2.4 | 7.98 | 3.1 |
Note: Values are means and standard deviations, unless otherwise noted. MD = math difficulty; no LD = no learning difficulties; WASI FSIQ = Wechsler Abbreviated Scale of Intelligence Full Scale IQ; WRAT-3 = Wide Range Achievement Test–3rd Edition; WJ-III = Woodcock–Johnson Tests of Academic Achievement–III; SWAN-IV = Strengths and Weaknesses of ADHD and Normal Behavior–4th Edition; Visual WM = Visual Working Memory from the Visuospatial Working Memory Task; Verbal WM = Verbal Working Memory from the Categorization Listening Span Task. Groups are significantly different on all measures, p < .01, except for sex and ethnicity.