Figure 1. Analytic Frameworks and Key Questions (KQs)

The analytic frameworks represent an outline of the evidence review and includes patient populations, interventions, outcomes, and adverse effects. The key questions examine a chain of evidence about the effectiveness, accuracy, and feasibility of screening asymptomatic children for elevated blood lead levelsin primary care settings, prevalence rates and risk factors, adverse effects of screening, effectiveness of interventions for children identified with elevated blood lead levels, adverse effects of interventions, and cost effectiveness issues.

Children:

[D] Select for Text Description.

• KQ1: Is there direct evidence that screening in asymptomatic children for lead results in improved health outcomes (i.e. cognitive changes, behavioral problems, learning disorders)?
• KQ2: What is the prevalence of elevated lead in children? Are there population-level risk factors that identify children at higher risk for elevated lead levels (i.e., geography, racial/ethnicity,SES, age)?
• KQ3: Can screening tests accurately detect elevated blood lead level?
  A. What is the accuracy of using questionnaires (or other tools)for risk factor assessment at various blood lead levels?
  B. What is the optimal frequency for screening? What is the optimal frequency for repeat testing?
• KQ4: What are the adverse effects of screening?
• KQ5: Do interventions (i.e., counseling families to reduce lead exposure, nutritional interventions, residential lead hazard control techniques, chelation therapy) for elevated lead levels result in improved health outcomes?
• KQ6: What are the adverse effects of the interventions?
• KQ7:What are the cost effectiveness issues?

Pregnant Women:

[D] Select for Text Description.

• KQ 1: Is there direct evidence that screening in asymptomatic pregnantwomen for lead results in improved health outcomes (i.e., cognitive changes in offspring, perinataloutcomes including birth weight/preterm delivery etc, maternal blood pressure)?
• KQ 2: What is the prevalence of elevated lead in asymptomatic pregnantwomen? Are there population-level risk factors that identify pregnant women at higher risk for elevated lead levels (i.e., geography, racial/ethnicity, SES, age)?
• KQ 3: Can screening tests accurately detect elevated blood lead levels? What is the accuracy of using questionnaires (or other tools) for risk factor assessment at various blood lead levels?
• KQ 4: What are the adverse effects of screening?
• KQ 5: Do interventions (i.e., counseling families to reduce lead exposure, nutritional interventions, residential lead hazard control techniques, chelationtherapy) for elevated lead levels result in improved health outcomes?
• KQ 6: What are the adverse effects of the interventions?
• KQ 7: What are cost effectiveness issues?

*Interventions include counseling families to reduce lead exposure, nutritional interventions, residential hazard control techniques, and chelation therapy.

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