How credible are the study results? Evaluating and applying internal validity tools to literature-based assessments of environmental health hazards. (July 2016)

• Record Type: Journal Article
• Authors: Rooney, Andrew A.; Cooper, Glinda S.; Jahnke, Gloria D.; Lam, Juleen; Morgan, Rebecca L.; Boyles, Abee L.; Ratcliffe, Jennifer M.; Kraft, Andrew D.; Schünemann, Holger J.; Schwingl, Pamela; Walker, Teneille D.; Thayer, Kristina A.; Lunn, Ruth M.
• Is Part Of: Environment international. Volume 92/93(2016:Jul.)
• Page Start: 617
• Page End: 629
• Publication Date: 2016-07
• Subjects: AHRQ Agency for Healthcare Research and Quality -- NTP National Toxicology Program -- OHAT Office of Health Assessment and Translation -- ORoC Office of the Report on Carcinogens -- EPA-IRIS Integrated Risk Information System of the U.S. Environmental Protection Agency -- GRADE Grading of Recommendations Assessment, Development, and Evaluation; Risk of bias -- Internal validity -- Systematic review -- Environmental health -- Hazard assessment; Environmental protection -- Periodicals; Environmental health -- Periodicals; Environmental monitoring -- Periodicals; Environmental Monitoring -- Periodicals; Environnement -- Protection -- Périodiques; Hygiène du milieu -- Périodiques; Environnement -- Surveillance -- Périodiques; Environmental health; Environmental monitoring; Environmental protection; Periodicals; 333.705
• DOI: 10.1016/j.envint.2016.01.005
• Languages: English
• ISSNs: 0160-4120

Abstract

Abstract: Environmental health hazard assessments are routinely relied upon for public health decision-making. The evidence base used in these assessments is typically developed from a collection of diverse sources of information of varying quality. It is critical that literature-based evaluations consider the credibility of individual studies used to reach conclusions through consistent, transparent and accepted methods. Systematic review procedures address study credibility by assessing internal validity or "risk of bias" — the assessment of whether the design and conduct of a study compromised the credibility of the link between exposure/intervention and outcome. This paper describes the commonalities and differences in risk-of-bias methods developed or used by five groups that conduct or provide methodological input for performing environmental health hazard assessments: the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group, the Navigation Guide, the National Toxicology Program's (NTP) Office of Health Assessment and Translation (OHAT) and Office of the Report on Carcinogens (ORoC), and the Integrated Risk Information System of the U.S. Environmental Protection Agency (EPA-IRIS). Each of these groups have been developing and applying rigorous assessment methods for integrating across a heterogeneous collection of human and animal studies to inform conclusions on potential environmental health hazards. There is substantial consistency across the groups in the consideration of risk-of-bias issues or "domains" for assessing observational human studies. There is a similar overlap in terms of domains addressed for animal studies; however, the groups differ in the relative emphasis placed on different aspects of risk of bias. Future directions for the continued harmonization and improvement of these methods are also discussed. Highlights: Systematic reviews address study credibility by assessing risk of bias. Five risk-of-bias methods for environmental health assessments are presented. The methods for assessing observational human studies had substantial consistency. Considerations for assessing animal studies were similar but applied differently. The diversity of environmental health evidence challenges risk-of-bias assessment.