Am Fam Physician. 2004;69(3):718
In children who may have lead exposure, the current recommendation is to perform screening to determine the necessity of obtaining a blood lead level. The Centers for Disease Control and Prevention (CDC) has established a questionnaire that can be used to assess lead exposure risk. As with most lead exposure risk-assessment questionnaires, the CDC version relies on information obtained from parents concerning the age of the home where the child lives. Multiple studies have shown that this questionnaire has a sensitivity of approximately 60 percent in predicting infants who would have elevated blood lead levels. This low sensitivity could be the result of parents being unable to provide accurate information about the age of their home. Schwab and associates conducted a study to determine the proportion of children who were correctly identified by their parents as living in housing built before 1950.
The study design was a cross-sectional survey of parents who accompanied their children to a pediatric residents' clinic and private pediatricians' offices for their nine-month to two-year well-child visits. The parents were asked about their children's lead exposure risk using a structured format that included questions about lead exposure that were published by the CDC. After the data were collected, information about the age of the children's homes was researched using tax assessment records. The main outcome measure was determining the sensitivity of the parents' response to a question asking if their home was built before 1950 or if their children spent time in other houses built before 1950.
There were 173 parents who completed the survey and lived within the study area. Using the tax records, the researchers identified 42 children who lived or spent time in a home built before 1950. Only 22 of the parents of these 42 children had responded that they lived in homes that put them at risk for lead exposure (sensitivity, 52 percent). Using the question about parental reporting of home age to assess lead exposure risk would have failed to identify 20 children who should have been screened for lead exposure by blood lead level testing.
The authors conclude that asking parents about the age of their home is no better than chance in selecting the children who are at risk for lead exposure because they live in or spend time in a house built before 1950.They add that relying on asking parents about the age of their home to determine which children should be screened for lead poisoning is inadequate.