Table 2.
Demographic and Clinical Characteristics of the Samples
| |
Clinic sample |
NHANES sample |
||||
|---|---|---|---|---|---|---|
| Males | Females | Total | Males | Females | Total | |
| n (%) | 79 (73) | 29 (27) | 108 | 1307 (49) | 1345 (51) | 2652 |
| Age (years), mean (SD) | 8.8 (2.7) | 9.6 (3.2) | 9.04 (2.8) | 11.8 (3.8) | 11.7 (3.7) | 11.8 (3.7) |
| Race, n (%) | ||||||
| Caucasian | 35 (44) | 13 (45) | 48 (44) | 389 (30) | 408 (31) | 797 (31) |
| African American | 24 (30) | 8 (28) | 32 (30) | 439 (32) | 407 (30) | 846 (31) |
| Hispanic | 7 (9) | 2 (7) | 9 (8) | 426 (33) | 474 (35) | 900 (34) |
| Other | 11 (14) | 3 (10) | 14 (13) | 53 (4) | 56 (4) | 109 (4) |
| Missing/Unknown | 2 (3) | 3 (10) | 5 (5) | 0 (0) | 0 (0) | 0 (0) |
| Family PIR, mean (SD) | Unknown | Unknown | Unknown | 2.1 (1.5) | 2.2 (1.6) | 2.1 (1.6) |
| Psychosocial adversity, n (%) | ||||||
| Category 1 (0 points) | 2 (2) | 0 (0) | 2 (2) | Unknown | Unknown | Unknown |
| Category 2 (1–2 points) | 17 (22) | 5 (19) | 22 (21) | Unknown | Unknown | Unknown |
| Category 3 (3–4 points) | 32 (42) | 9 (33) | 41 (40) | Unknown | Unknown | Unknown |
| Category 4 (5–8 points) | 25 (33) | 13 (48) | 38 (37) | Unknown | Unknown | Unknown |
| Missing/Unknown | 3 (4) | 2 (7) | 5 (5) | Unknown | Unknown | Unknown |
| Psychiatric disorders, n (%) | ||||||
| ADHD | 60 (77) | 22 (76) | 82 (77) | 34 (7) | 37 (7) | 71 (7) |
| ODD | 28 (35) | 13 (45) | 41 (38) | Unknown | Unknown | Unknown |
| Other DBD | 21 (27) | 4 (14) | 25 (24) | Unknown | Unknown | Unknown |
| Any mood disorder | 23 (29) | 9 (31) | 32 (30) | Unknown | Unknown | Unknown |
| Any anxiety disorder | 30 (38) | 8 (28) | 38 (35) | Unknown | Unknown | Unknown |
| PDD/Autism | 2 (3) | 0 (0) | 2 (2) | Unknown | Unknown | Unknown |
| Intellectual disability | 4 (5) | 1 (4) | 5 (5) | Unknown | Unknown | Unknown |
| Speech disorder | 15 (20) | 3 (12) | 18 (18) | Unknown | Unknown | Unknown |
| Learning disorder | 13 (17) | 3 (11) | 16 (15) | 46 (13) | 35 (10) | 81 (11) |
| Serum ferritin, mean (SD) | 27.2 (14.7) | 23.3 (12.0) | 26.2 (14.1) | 82.3 (105.2) | 82.7 (112.2) | 82.5 (108.8) |
| Normal range: 10–300 μg/L | ||||||
| Hemoglobin, mean (SD) | 12.6 (1.0) | 12.2 (0.6) | 12.5 (0.9) | 14.1 (1.35) | 13.2 (1.04) | 13.9 (1.54) |
| Normal range: age<11=11.7–13.8 g/dL; age ≥11=12.4–14.8 g/dL | ||||||
| Low hemoglobin, n, (%) | 13 (16) | 8 (28) | 21 (19) | 34 (2.6) | 151 (11) | 185 (7.0) |
| RDW, mean (SD) | 12.9 (0.6) | 12.9 (0.9) | 12.9 (0.8) | 12.5 (0.673) | 12.4 (0.918) | 12.4 (0.807) |
| Normal range:11.5–14.5% | ||||||
| ESR, mean (SD) | 6.8 (5.7) | 11.6 (11.2) | 8.2 (7.9) | 12.5 (0.673) | 12.4 (0.918) | 12.4 (0.807) |
| Normal range: 4–20 mm/hour | ||||||
| Lead | 1.0 (1.9) | 0.3 (1.1) | 0.8 (1.7) | 1.9 (1.8) | 2.0 (2.4) | 2.0 (2.1) |
| C-reactive protein, mean (SD) | Unknown | Unknown | Unknown | 0.299 (0.502) | 0.364 (0.860) | 0.332 (0.709) |
| Normal range: <1 mg/dL | ||||||
NHANES, National Health and Nutrition Examination Survey; PIR, poverty index ratio; ADHD, attention-deficit/hyperactivity disorder; ODD: oppositional defiant disorder; DBD, disruptive behavior disorder; PDD: pervasive developmental disorder; RDW, red blood cell distribution width; ESR, erythrocyte sedimentation rate.