Table 1. Sample Characteristics by Group.
| Characteristic | FXS (n = 27) | Control (n = 73) | Test Statistic | P Value |
|---|---|---|---|---|
| Longitudinal visit complement, No. | ||||
| At 6-mo visit | 14 | 68 | NA | NA |
| At 12-mo visit | 18 | 50 | NA | NA |
| At 24-mo visit | 10 | 46 | NA | NA |
| Age at 6-mo visit, mean (SD), mo | 6.5 (0.8) | 6.7 (0.7) | t80 = −1.05 | .29 |
| Age at 12-mo visit, mean (SD), mo | 12.6 (0.8) | 12.6 (0.6) | t80 = 0.13 | .90 |
| Age at 24-mo visit, mean (SD), mo | 24.7 (1.0) | 24.8 (1.3) | t80 = −0.20 | .83 |
| Male sex, No. (%) | 22 (81.5) | 46 (63.0) | χ2 = 3.08 | .07 |
| Child race, No. (%) | ||||
| White | 22 (81.5) | 59 (80.8) | χ2 = 1.95 | .74 |
| African American | 0 | 3 (4.1) | ||
| Asian | 0 | 1 (1.4) | ||
| >1 Race/ethnicity | 3 (11.1) | 7 (9.6) | ||
| Not answered | 2 (7.4) | 3 (4.1) | ||
| Maternal educational level, No. (%) | ||||
| High school diploma | 10 (37.0) | 10 (13.7) | χ2 = 16.63 | <.001 |
| College degree | 14 (51.9) | 30 (41.1) | ||
| Graduate degree | 2 (7.4) | 33 (45.2) | ||
| Missing | 1 (3.7) | 0 |
Abbreviations: FXS, fragile X syndrome; NA, not applicable.