The survey was conducted during the 1993–1994 school year. The sampling design used three-stage cluster sampling with school districts as primary sampling units and classrooms from grades K, 1, 2, and 8 as the observational sampling units. Selections were made using probability-proportional-to-size design (979 schools). Standard visual/tactile diagnostic criteria from the National Institute of Dental Research (NIDR, now the National Institute of Dental and Craniofacial Research) were used to obtain the DMFS index (number of decayed, missing or filled tooth surfaces). All examiners were trained and calibrated. Based on the sample design and response rates, weights for use in data analysis were calculated at the classroom level. The combined probability of selection of the school district, school, and classroom was multiplied by the response rate for the class. The inverse of this overall probability of being examined was the weight assigned to the student record for use in data analysis. Estimates were adjusted for nonresponse.

For more information about this survey, contact:

Sangeeta Wadhawan, BDS, MPH
Illinois Department of Public Health
Division of Oral Health
535 W. Jefferson Street
Springfield, IL 62761
Telephone: 217-785-4899
Fax: 217-524-2831
E-mail: swadhawa@idph.state.il.us