Mean Wechsler FSIQ scores obtained from children with SCD and sibling controls as reported in 8 studies. The horizontal black line represents the mean value for each category of children. FSIQ scores have a mean of 100 (SD 15). Scores above 80 are within the average range according to Wechsler classification.27 (A) Armstrong et al22 (Normal MRI, n = 105; Silent Infarct, n = 21; Clinical History of Stroke, n = 9; age range, 6-12 years). (B) Steen et al33 (Historical Control Data, n = 30; Normal cMRI, n = 12; Abnormal cMRI, n = 10; mean age, 10 years; SD, 3 years). (C) Watkins et al4 (Control, n = 15; SCD/nm, n = 15; Asymptomatic, n = 4; Symptomatic, n = 5; age range, 5-16 years). (D) Bernaudin et al17 (Siblings, n = 76; Normal MRI, n = 104; Silent Stroke, n = 17; With (Overt) Stroke, n = 11; age range, 5-15 years). (E) Brown et al31 (no cerebrovascular accident [CVA], n = 30; Silent, n = 11; CVA, n = 22; age range, 6-17 years). (F) Wang et al28 (Normal MRI, n = 122; Silent Infarct, n = 43; Stroke, n = 20; age range, 6-18 years). (G) Thompson et al64 (First Visit: Normal, n = 93; Silent Infarct, n = 29; Stroke, n = 6; age range, 5-15 years). (H) Steen et al65 (African-American Controls, n = 30; Patients, n = 30; mean age, 10 years; SD, 2.9 years).