1. State your health outcome of interest. (It could be the one you used for week #2 or another one.) Pick two key behaviors that are important factors leading to your health outcome. Explain the importance of these behaviors either for etiology, prevention, or intervention. (If none of the behaviors in the readings are important for your health outcome, suggest another behavior that is.)
Looking at preterm birth as an outcome, two associated behaviors are illicit drug use and nutritional status. Both are likely contributory for etiology. Illicit drug use can act as an etiologic factor for preterm birth via two mechanisms. First, directly via pathophysiologic pathways; for example, cocaine can cause preterm labor, placental abruption and hypertensive disorders in pregnancy, each which can lead to preterm birth. Secondly, the illicit drug use can be a proxy marker for other poor health behaviors, such as poor prenatal care, which also contributes to the risk of preterm birth. If the illicit drug use is stopped prior to pregnancy, the outcomes improve, compared to those still using drugs. Regarding nutritional status and weight gain during pregnancy has been shown to be associated with preterm birth. The effect is not seen in overweight and obese women, presumptively because they can compensate with excess body weight. However, underweight and normal weight women with poor weight gain during pregnancy have an increased risk of preterm birth.
2. Describe how you would study the role of one of the behaviors described for question #1 and your health outcome of interest. Incorporate a social factor (e.g. race/ethnicity, social exclusion, stress) in the study approach.
Two arm randomized control trial, with cluster randomization, where one arm (intervention) is an educational intervention aimed at improving maternal nutrition during pregnancy through targeted sessions and the other arm (active control) uses an educational tool about parenting. The primary outcome is preterm birth; secondary outcome is gestational week specific weight gain. Stress will be considered a predictor, and will be measured via standard questionnaire every 4 weeks.
3. If key health behaviors (e.g. smoking, exercise, nutritious diet) are strongly influenced by neighborhood, income, and/or education, do we need to continue to study how these behaviors influence health outcomes? Why or why not?
There may be compounding or synergistic effects of multiple risk factors. This effect could be lost in analysis if all behavior risks are not examined separately. Additionally, we cannot presume that intervening on income or education, for example, would improve the outcome, if the behavior is still present. As such, behaviors should be studied as well as other social factors.