Table 2.

Descriptive statistics at all times of assessment

Visits→	Visit 1	Visit 2	Visit 3	Visit 4
Variables	Mean (SD) [range]	Mean (SD) [range]	Mean (SD) [range]	Mean (SD) [range]
Chronological age	12 (1.5) [10–16]	13 (1.5) [11–17]	14 (1.5) [12–18]	15 (1.5) [13–19]
Biological predictors
Ratio of affected to total chromosomes	56.47 (19.92) [27–88]
Level of FMRP expression	0.48 (0.05) [0.34–0.51]
Maternal predictors
Maternal psychological distress	51.5 (11.6) [30–65]
Closeness in the mother–child relationship	23.5 (4.1) [16–28]
Dependent variables
Fluid intelligence (SS)	68 (13.6) [48–90]	70.3 (15.5) [48–100]	62.9 (12.6) [48–88]	66.5 (15.2) [48–102]
Fluid intelligence (RS)	33.9 (12.8) [17–55]	38.9 (11.6) [18–58]	37.4 (13.3) [17–61]	39.8 (13.1) [20–61]
Crystallized intelligence (SS)	81.2 (17.6) [51–107]	84 (16.3) [57–112]	81.3 (15.7) [52–100]	82.7 (20.9) [41–109]
Crystallized intelligence (RS)	87.8 (19.8) [53–120]	95.9 (20.3) [64–132]	96.6 (20.2) [62–135]	103.8 (25) [62–148]
Anxious behaviors (TS)	59.53 (10.01) [50–84]	60 (7.7) [50–72]	60.1 (8.2) [50–74]	58.2 (7.2) [50–70]
Withdrawn behaviors (TS)	62.5 (11.6) [50–87]	59.8 (9.4) [50–81]	64.4 (10.7) [50–81]	62 (11.8) [50–85]

Abbreviations: SS standardized score (mean of 100, standard deviation of 15), RS raw score, TS T-score (mean of 50, standard deviation of 10)