TABLE 1.

Sample Characteristics at Enrollment

Mean age of parents43.1y
Race93.6% White
Family income
 $90 000+16.1%
 $65 000–$90 00035.5%
 $40 000–$65 00025.8%
 $15 000–$40 00019.4%
 Less than $15 0003.2%
Education level
 Graduate/professional degree42.2%
 College30.4%
 Partial college17.0%
 High school8.9%
 Partial high school1.5%
Number of children121 (57.3% male)
Mean age of children11.6 y
  • There were no significant group differences in any of these categories.