Table 1.

General characteristics of the participants (N=964)

Characteristics	Participants
Age in years, mean	30 (10–49)
Age goup
10–19	13.5%
20–29	39.8%
30–39	30.6%
40–49	16.1%
Marital status
Single	22.1%
Married/living together	59.8%
Divorced/separated	18.1%
Education
Less than high school	22.9%
High school	22.2%
University	54.9%
Social Strata (Hollingshead)
Class I	6.6%
Class II	26.8%
Class III	17.7%
Class IV	12.5%
Class V	36.3%
Family history of NTD	4.9%