A COMPARISON OF SCREENING STRATEGIES FOR ELEVATED BLOOD LEAD LEVELS

Objective: To calculate and compare the average expected cost per chil d screened (hereafter referred to as COST) among various screening str ategies. Design: A decision analysis of 5 strategies: (1) conduct risk assessment and screen high-risk children by venipuncture, low-risk ch ildren by fingerstick; (2) screen all children by fingerstick; (3) scr een all children by venipuncture; (4) conduct risk assessment, screen high-risk children by fingerstick; and (5) conduct risk assessment, sc reen high-risk children by venipuncture. We assumed all fingerstick bl ood lead levels of 0.72 mu mol/L or higher (greater than or equal to 1 5 mu g/dL) would be confirmed by venipuncture. Baseline variables take n from the literature included prevalence of elevated blood lead level s in the pediatric population (2%), sensitivity and specificity of fin gerstick blood lead assay (90% each), specificity of risk assessment ( 50%), sensitivity of risk assessment at blood lead levels of 0.48 to 0 .68 mu mol/L (10-14 mu g/dL) and 0.72 mu mol/L or higher (greater than or equal to 15 mu g/dL) (65% and 85%, respectively), cost of blood le ad assay ($6), cost to obtain blood by venipuncture ($4) and fingersti ck ($2), and cost to get a child who has a fingerstick blood lead leve l of 0.72 mu mol/L or higher (greater than or equal to 15 mu g/dL) to return ($0.18). Sensitivity analysis determined whether selected varia bles affected the COST. Results: The COSTs for strategies 1 through 5 were $9.07, $8.16, $10, $4.13, and $5.04, respectively. Among the univ ersal strategies, screening children by fingerstick had the lowest COS T at a prevalence of less than 38% and fingerstick blood lead assay a specificity of greater than 62%. Among the selective strategies, scree ning highrisk children by fingerstick had the lowest COST at a prevale nce of less than 38% and fingerstick blood lead an assay specificity o f greater than 63%. Conclusion: At a readily attainable specificity of the fingerstick blood lead assay, practices serving a patient populat ion with a prevalence of elevated blood lead levels of less than 38% w ill have the lowest COST when a fingerstick screening strategy is used .