Table 1.
Subject characteristics
| Cocaine (N = 177)
|
Non-cocaine (N = 175)
|
t/χ2 |
p |
|||||
|---|---|---|---|---|---|---|---|---|
| Mean | S.D. | N (%) | Mean | S.D. | N (%) | |||
| Maternal demographics | ||||||||
| Age (years) | 30.1 | 5 | 25.7 | 5 | −8.4 | 0.0001 | ||
| Parity | 3.5 | 2 | 2.8 | 2 | −3.6 | 0.0004 | ||
| Number of prenatal visits | 5.3 | 4 | 8.7 | 5 | 6.9 | 0.0001 | ||
| Education (years) | 11.7 | 2 | 11.9 | 1 | 1.3 | 0.18 | ||
| PPVT-R score | 73.5 | 15 | 78.1 | 15 | 2.9 | 0.00 | ||
| WAIS-R block design score | 8.0 | 2 | 7.2 | 2 | 1.7 | 0.08 | ||
| WAIS-R picture completion score | 6.5 | 2 | 7.0 | 2 | 1.9 | 0.06 | ||
| Global Severity Index | 0.8 | 0.7 | 0.5 | 0.5 | −4.9 | 0.0001 | ||
| African-American | 153 (87%) | 141 (81%) | 2.2 | 0.14 | ||||
| Married | 14 (8%) | 31 (18%) | 7.6 | 0.006 | ||||
| Maternal employment | 10 (6%) | 38 (22%) | 19.3 | 0.0001 | ||||
| Low socioeconomic status | 173 (99%) | 172 (98%) | 0.1 | 0.99 | ||||
| Prenatal drug exposure | ||||||||
| Cigarettes/day | 10.6 | 9 | 4.3 | 8 | −9.5 | 0.0001 | ||
| Alcohol drinks/week | 9.5 | 18 | 1.4 | 4.5 | −9.9 | 0.0001 | ||
| Marijuana joints/week | 1.3 | 3 | 0.6 | 4 | −3.8 | 0.001 | ||
| Cocaine rocks/week | 23.3 | 46 | ||||||
| Cocainea,* | 0 (0–3112) | |||||||
| Cocaethylenea,* | 0 (0–419) | |||||||
| Benzoylecgoninea,* | 27 (0–9998) | |||||||
| Metahydroxy-benzoylecgoninea,* | 0 (0–9998) | |||||||
| Alcohol | 144 (85%) | 112 (66%) | 16.8 | 0.0001 | ||||
| Marijuana | 83 (49%) | 24 (14%) | 47.9 | 0.0001 | ||||
| Tobacco | 148 (87%) | 71 (42%) | 76.9 | 0.0001 | ||||
| Amphetamine** | 3 (2%) | 2 (1%) | 0.2 | 0.68 | ||||
| Barbiturate** | 1 (1%) | 1 (1%) | 0.0 | 0.99 | ||||
| Benzodiazepine** | 18 (14%) | 0 (0%) | 20.0 | 0.0001 | ||||
| Phencyclidine** | 9 (5%) | 0 (0%) | 9.3 | 0.002 | ||||
| Infant characteristics | ||||||||
| Corrected age at test (weeks) | ||||||||
| 6.5 months | 29.02 | 2.93 | 29.11 | 3.34 | .24 | 0.81 | ||
| 12 months | 54.26 | 5.23 | 53.54 | 3.34 | −1.38 | 0.17 | ||
| Birth length (cm) | 47.4 | 4 | 49.0 | 3.4 | 4.1 | 0.0001 | ||
| Gestational age (week) | 37.8 | 3 | 38.5 | 3 | 2.1 | 0.03 | ||
| Birthweight (g) | 2738 | 649 | 3090 | 696 | 4.9 | 0.0001 | ||
| Head circumference (cm) | 32.3 | 2 | 33.5 | 2 | 4.7 | 0.0001 | ||
| Hobel neonatal risk score | 6.7 | 16 | 6.1 | 16 | −0.4 | 0.73 | ||
| Gender (male) | 77 (44%) | 87 (50%) | 1.4 | 0.24 | ||||
a
Nanograms/gram in meconium.
*
Medians (minimum and maximum).
**
Fisher’s exact test.