Understanding health risks and interpreting them correctly is an important function for anyone involved in public health.
Often, the results of epidemiological studies are reported in the media as "known facts," when indeed that is not the case.
Such is the situation for the reported association between vaccinations and the risk of autism.
For this Case Study Assignment, you will analyze and interpret the epidemiological evidence for a possible association between vaccination with the measles/mumps/rubella (MMR) vaccine and the occurrence of autism
Using the information provided in the case study, complete Sections B, C, and D (pp. 5-10), typing your answers into a separate document.
Be sure that your completed document contains your responses to all questions from Sections B, C, and D of the case study.
Section B: Calculating Measures of Association
Over 25 studies have been conducted which have failed to show an association between MMR vaccine and autism. Below are some data from two of these studies (one cohort and one case-control). Calculate the measure of association for each study after completing the 2x2 table and interpret the measure of association.
1. Cohort study by Madsen et al (NEJM 2002) Of the 537,303 children in the cohort, 440,655 (82.0 percent) had received the MMR
vaccine. We identified 316 children with a diagnosis of autistic disorder; 263 of the cases had been vaccinated with MMR (83%); 53 children with autism had not been vaccinated.
2. Case control study by Smeeth et al (Lancet 2004) 1294 cases of pervasive developmental disorder (PDD) and 4469 controls were included. 1010 cases (78·1%) had MMR vaccination recorded before diagnosis, compared with 3671 controls (82·1%) before the age at which their matched case was diagnosed.
Section C: Interpreting results
Review the following data from the aforementioned studies and answer the following questions.
1. Describe the characteristics in Table 1 in terms of what type of data they are (discrete / qualitative versus continuous / quantitative).
Using the chi-square test (see footnote of FIGURE 1), authors found significant differences in certain characteristics of vaccinated and unvaccinated children.
2. What characteristics showed no differences between the two groups? What characteristics showed differences between the vaccinated and unvaccinated groups?
3. What do these differences mean?
4. Do the data in Figure 2 above show an association between MMR vaccine and risk of autism?
5. Do the data in Figure 3 from Smeeth et al show an association between MMR vaccine and risk of autism?
Section D: Conclusion
Since 1998, numerous well-designed studies have found no link between vaccines and autism (see table below). Why do you think some parents are still fearful of vaccines? What is your role as future healthcare providers in counseling patients about vaccines?
Attachment:- module_case.rar