Background: The Navigation Guide methodology was developed to meet the need for a robust method of systematic and transparent research synthesis in environmental health science. We conducted a case study systematic review to support proof of concept of the method.
Objective: We applied the Navigation Guide systematic review methodology to determine whether developmental exposure to perfluorooctanoic acid (PFOA) affects fetal growth in humans.
Methods: We applied the first 3 steps of the Navigation Guide methodology to human epidemiological data: 1) specify the study question, 2) select the evidence, and 3) rate the quality and strength of the evidence. We developed a protocol, conducted a comprehensive search of the literature, and identified relevant studies using prespecified criteria. We evaluated each study for risk of bias and conducted meta-analyses on a subset of studies. We rated quality and strength of the entire body of human evidence.
Results: We identified 18 human studies that met our inclusion criteria, and 9 of these were combined through meta-analysis. Through meta-analysis, we estimated that a 1-ng/mL increase in serum or plasma PFOA was associated with a –18.9 g (95% CI: –29.8, –7.9) difference in birth weight. We concluded that the risk of bias across studies was low, and we assigned a “moderate” quality rating to the overall body of human evidence.
Conclusion: On the basis of this first application of the Navigation Guide systematic review methodology, we concluded that there is “sufficient” human evidence that developmental exposure to PFOA reduces fetal growth.
1Program on Reproductive Health and the Environment, University of California, San Francisco, Oakland, California, USA; 2Oak Ridge Institute for Science and Education (ORISE) Postdoctoral Fellowship, National Center for Environmental Economics, Office of Policy, U.S. Environmental Protection Agency, Washington, DC, USA; 3Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, California, USA; 4Department of Medicine, 5Department of Epidemiology, and 6Department of Health Policy & Management, Johns Hopkins University, Baltimore, Maryland, USA; 7National Center for Environmental Economics, Office of Policy, U.S. Environmental Protection Agency, Washington, DC, USA
Recommended Citation:
Paula I. Johnson,1 Patrice Sutton,1 Dylan S. Atchley,et al. The Navigation Guide—Evidence-Based Medicine Meets Environmental Health: Systematic Review of Human Evidence for PFOA Effects on Fetal Growth[J]. Environmental Health Perspectives,2014-01-01,Volume 122(Issue 10):1028