Critical evaluation of epidemiological studies Authors of a range of epidemiological texts have each developed their own set of criteria for evaluation. The following outline is devised primarily from Aschengrau&Seage, (2008) and Greenberg et al., (2005). Consider: study objectives and design 1. What was the context of the study (this includes the researchers’ motivation for conducting the study)? 2. What were the objectives of the study? Is the research hypothesis clear? Is the research topic relevant/purposeful? 3. What is the study design? Is it observational or experimental? Is the study design useful for measuring the research exposure and health outcome? Consider: study parameters: study and source population; exposure and outcome factors 4. What was the primary exposure of interest? How is it measured? Is it accurately assessed? 5. What is the primary outcome of interest? How is it measured? Is it accurately assessed? 6. Describe the source of the study population; process of subject selection; sample size; if applicable “ the ratio of exposed to unexposed or comparison subjects. Consider: the methods and the analysis 7. What measures of association were reported in the study? 8. Has the statistical significance of the results been reported? 9. Has chance been considered as a potential explanation for the results? Consider: potential sources of bias and confounding 10. Could there have been bias in the selection of the study subjects? How likely was this bias? 11. Could there have been measurement bias in the study? How likely was this bias? 12. What measures were undertaken to address the influence of potential confounders prior to data analysis? Was this sufficient? 13. What measures were undertaken to control confounding during data analysis? Was this sufficient? Consider: the interpretation of the results and their application 14. What were the major results of the study? 15.Is the temporal relationship of exposure and health outcome clear? 16. Are the results consistent with other findings? 17. Is there a biological gradient (dose-response relationship)? 18. Are the effects biologically plausible? 19. How is the interpretation of the results affected by bias and/or confounding? What is the direction and magnitude of any bias? 20. Evaluate the discussion section of the study. Does it adequately address the limitations of the study? 21. What are author’s main conclusions? Are they justified by the research? 22. Can the study be generalised to a wider population? 23. Is the knowledge derived from this study new? Does it support a change to current thinking? Assessment 2: Task: It is important for health care professionals to critically evaluate published research literature. The task for Assignment 2 is to undertake a critical evaluation of a published research article. The research article for review is: Shi, Z., Dal Grande, E., Taylor, A., Gill, T., Adams, R., &Wittert, G. (2012).Association between soft drink consumption and asthma and chronic obstructive pulmonary disease among adults in Australia.Respirology, 17, 363-369.