02 Legal, Ethics and Public Health Policy in Epidemiology.pptx

02 Legal, Ethics and Public Health Policy in Epidemiology.pptx

1. Legal, Ethics and public health policy in Epidemiology Soo Kuan Meng Lecture 02 (12 Jan 2023) 1

2. Learning outcomes To explain the role of epidemiology in disease prevention, risk assessment and making public policy To explain the use of systematic review and meta-analysis in making public policy To explain the ethical obligations of investigators towards subjects including protecting the privacy of subjects, conflict of interest and disseminating the finding To explain the impact of using race and ethnicity as variable of study 2

3. Health policy 3

4. Role of epidemiology in disease prevention includes Identify populations at increased risk Ascertaining cause of increased risk Analysing cost and benefits of reducing exposure to causal factors Assessing strength of available evidence, identify limit of inferences and its generalizability 4

5. Role of epidemiology in disease prevention includes Diagram of expanded risk factor epidemiology model to include interrelationships of factors that determine susceptibility to disease 5

6. Role of epidemiology in disease prevention includes How the end point may affect an individual’s perception of risk and willingness to act 6

7. Contrast two possible strategies for prevention: Primary prevention- target groups at high risk for disease Those who are aware that they are at high risk are more likely to tolerate more expensive, invasive, uncomfortable procedures Secondary prevention- focus on general population. For secondary prevention, aside from focus on the disease in question, we also consider to detect or screen the disease earlier, the cost and invasive of the screening test, the benefits and harmful effects of screening test. Preventive measure applied to a general population must have a low cost and be minimally invasive, little pain or discomfort 7

8. Contrast two possible strategies for prevention: Effect of population based intervention strategy on the distribution of blood pressure. Population based intervention to reduce blood pressure could be the reduction of salt content of processed food. This causes lowering of the systolic (diastolic) blood pressure. 8

9. Contrast two possible strategies for prevention: Kaplan-Meier estimates of the cumulative incidence of coronary heart disease events. Hormone replacement therapy (HRT) on postmenopausal women showed no protection towards coronary heart disease events, when compared with placebo. 9

10. Contrast two possible strategies for prevention: Disease rate for women assigned to estrogen plus progestin (HRT) or to placebo This component of study was stopped 3 years early because results had shown increased risks of heart attack, stroke, breast cancer and blood clot. 10

11. Definition of risk assessment Risk assessment is the characterization of potential adverse health effects of human exposures to environmental hazards. Risk assessment includes process from risk assessment, dose response assessment, risk communication to public and risk management 11

12. Definition of risk assessment What exposures are we trying to measure? 12

13. Role of epidemiology in risk assessment Epidemiology data is needed for risk assessment, including measurement of exposures through: Aggregate exposure Personal exposure Occupational exposure Use of biologic markers of exposures (molecular epidemiology) 13

14. How epidemiology can be used to shape public policy Epidemiology provide the scientific evidence that is relevant to the questions involved such as issues related to effects of dioxin, tobacco smoking. Therefore judges must have a knowledge of epidemiologic concepts- including study design, biases and confounding, and causal inference 14

15. Systematic review and meta-analysis as tools to summarize all the available epidemiologic evidence Given results of different epidemiologic studies may be inconsistent, systematic review and meta-analysis are used. Systematic review use standardized methods to select and assess articles to synthesize the literature regarding a specific health topic. Meta-analysis is the statistical analysis of a large collection of analysis results form individual studies in order to integrate the findings Forest plot is the type of presentation used to show the results of individual studies 15

16. Systematic review and meta-analysis as tools to summarize all the available epidemiologic evidence Hypothetical forest plot, showing results of individual studies (A-E), as well as the results of a meta-analysis 16

17. Systematic review and meta-analysis as tools to summarize all the available epidemiologic evidence Odds ratios for major depression in lowest socioeconomic status group in 51 prevalence studies. Squares showed original studies, diamond showed meta-analysis results 17

18. Effect of publication bias towards systematic reviews and meta-analyses Systematic review is subject to problem of publication bias. Publication bias is a bias that occur because: investigators do not submit the results of their studies when the findings do not support “positive” associations and increased risks (or “null findings”) journals may select publication studies that they believe of greater reader interest, and they believe that studies that report no association are not of reader interest. Thus, literature review is limited to published articles which show increased risk and causes bias. One approach is to include unpublished studies or assess the publication bias by using statistical tests such as Begg’s test. 18

19. Sources of uncertainty in using epidemiologic studies as basis to make public policy Study design Such as anecdotal evidence that is without comparison group Conduct and implementation of the study Presentation and interpretation of the study findings The use of different estimation of risk such as relative risk reduction, absolute risk reduction, percent reduction in mortality can give different results Ultimately the impact of uncertainty will depend on how the policy maker consider uncertainty. 19

20. Sources of uncertainty in using epidemiologic studies as basis to make public policy One jury’s approach to uncertainty 20

21. Sources of uncertainty in using epidemiologic studies as basis to make public policy Schematic presentation of some of the factors involved in the impact of uncertainty on the decision making process for health policy 21

22. Ethics 22

23. Ethical obligations of investigators towards respondents A truly informed consent should be obtained from every subject. This consent is done by informing the subjects of the study’s objectives and hypotheses. To protect the privacy and confidentiality of subjects. Assurance of confidentiality is given by including qualifications to allow for breaches in confidentiality that could be legally mandated. To communicate the results of the study to the subjects at the study’s completion in disease prevention and control. 23

24. Ethical obligations of investigators towards respondents “no man is an island” John’s Donne worldview, stressing people’s interdependence 24

25. Way to protect privacy and confidentiality Legislative proposals as follows: Patient consent should be required before investigators are allowed access to medical records. informed consent language must be consistent with the educational level of the participant Data from medical records should be made available to investigators without any information that would identify an individual. Only study numbers are used on data forms, no personal identifiers are available. The key for linking study numbers with individual names is kept separately under lock and key. Individual identifying information is destroyed at the end of study unless committee on human research approve on retaining the information 25

26. Way to protect privacy and confidentiality Sample consent form. 26

27. Scientific and ethical implications of classifying race and ethnicity in study May not be scientific because existing racial classification schemes are the result of historical and political processes and that there is nothing natural, objective or scientific about them. Race is also ill defined (some can identify themselves with more than one racial group). Another variable being used is ethnicity. Ethnicity is a complex variable that implies shared origins or social backgrounds; shared culture and traditions and religions. there is no clear difference in genetic diversity between different racial groups by emphasizing the negative aspects of the health of ethnic minority groups, research may have damaged their social standing ( eg becomes surrogates for undesirable lifestyle or characteristics) and deflected attention from their health priorities hence, the use of racial variables should have a definite purpose 27

28. Issues associated with conflict of interest Conflict of interest may arise at each stage of a study, from initial decision to carry out a study through analysis and interpretation of the data and dissemination of the results. Examples of conflict of interest Academic epidemiologists may seek external financial support from government, industry or foundations. Thus their research are subjected to careful peer review. And the researcher generally has no interest in the outcome of the results Government and industry epidemiologists seek internal funding. Employer may be affected by the research findings. Serious bias may be introduced in review of literature and these biases may be impossible to assess. 28

29. Way to interpret and disseminate the finding Epidemiologist must learn to work with the media, including radio, television, magazines and newspapers and with social media to further their educational efforts. They could communicate the findings for preventive measures including lifestyle changes 29

30. Way to interpret and disseminate the finding One view of the seemingly endless stream of reported risks confronting public 30

31. Way to interpret and disseminate the finding Dealing with scientific uncertainty 31

32. Way to interpret and disseminate the finding Risk of death per person per year For many of the risks listed, the degree of public concern and the change in behaviour do not seem commensurate with the magnitude of the risk 32

33. Way to interpret and disseminate the finding Risk of death per person per year For many of the risks listed, the degree of public concern and the change in behaviour do not seem commensurate with the magnitude of the risk 33