Week 3 Discussion

Week 3 Discussion

by Chloe Eng -

  1. SUPREME-DM (SUrveillance, PREvention, and ManageEment of Diabetes Mellitus) DataLink: SUPREME-DM includes de-identified health information from nearly 1.1 million people with diabetes in 10 states: California, Colorado, Georgia, Hawaii, Michigan, Minnesota, Oregon, Pennsylvania, Washington and Wisconsin. Participating health plans include six regions of Kaiser Permanente, Geisinger Health System, Group Health Cooperative, Health Partners, Henry Ford Health System and Marshfield Clinic. 

  1. Strong research question:  How does the timing of diabetes onset affect stroke risk among diverse racial groups?  

  1. This sample encompasses urban and rural regions, includes both private insurance and Medicaid/Medicare-insured individuals, and is comprised of a diverse racial and ethnic range, making it well equipped to answer questions of clinical outcomes across a wide range of socioeconomic status. 

  1. Weak research question: What is the national prevalence of diabetes in the US? 

  1. SUPREME-DM only has the ability to answer questions about patient subgroups - population-level inferences are not possible, as this datalink only covers a fraction of the states and is not representative of the US. It also does not cover individuals who are not enrolled in insurance programs and/or who do not attend health organizations. 

  1. Monitoring the Future (MTF): MTF is a trend study, that implements cross-sectional nationally representative surveys of high school seniors, collected since 1976 (and for 8th and 10th graders since 1991).  

  1. Strong research question: Did teenage attitudes towards cigarette use shift following the implementation of minimum age cigarette purchasing restrictions? 

  1. MTF questionnaires cover a wide range of topics, including attitudes towards drug use, planned career trajectories, and drug use patterns, making it apt for measuring population average changes and trends over time.  

  1. Weak research question: Do teenage attitudes towards drug use persist into young adulthood? 

  1. MTF is unable to examine long-term outcomes, as surveys collect information only on cross-sectional points in time and don't follow individuals longitudinally.  

  1. Panel Study of Income Dynamics (PSID): PSID is a panel study, a type of longitudinal study design defined as describing cases at two points or more in time. Panel studies differ from cohort studies, which follow cohorts (a group of people selected for their inclusion in a “cohort”, often based on age/year of birth) at often infrequent intervals in that they generally sample from the entire age range, and are used extensively to monitor poverty dynamics, movements into and out of the labor market, and demographic change. 

  1. Strong research question: Are there differences in long-term downstream effects of self-earned income verses spousal earned income on mortality (e.g. does the act of earning income differ from having access to income)? 

  1. PSID includes multiple generations of families, making it well suited to answer questions regarding intergenerational characteristics and life-course exposures over time. 

  1. Weak research question: Are effects of the "healthy immigrant" generalization on mortality mediated through income? 

  1. Although the PSID is designed to be nationally representative, there is little information on immigrants. Furthermore, PSID is subject to reactivity (responses to subsequent questions being affected by prior questions) and retention as participants are repeatedly surveyed.

  1. SUPREME-DM (SUrveillance, PREvention, and ManageEment of Diabetes Mellitus) DataLink: SUPREME-DM includes de-identified health information from nearly 1.1 million people with diabetes in 10 states: California, Colorado, Georgia, Hawaii, Michigan, Minnesota, Oregon, Pennsylvania, Washington and Wisconsin. Participating health plans include six regions of Kaiser Permanente, Geisinger Health System, Group Health Cooperative, Health Partners, Henry Ford Health System and Marshfield Clinic. 

  1. Strong research question:  How does the timing of diabetes onset affect stroke risk among diverse racial groups?  

  1. This sample encompasses urban and rural regions, includes both private insurance and Medicaid/Medicare-insured individuals, and is comprised of a diverse racial and ethnic range, making it well equipped to answer questions of clinical outcomes across a wide range of socioeconomic status. 

  1. Weak research question: What is the national prevalence of diabetes in the US? 

  1. SUPREME-DM only has the ability to answer questions about patient subgroups - population-level inferences are not possible, as this datalink only covers a fraction of the states and is not representative of the US. It also does not cover individuals who are not enrolled in insurance programs and/or who do not attend health organizations. 

  1. Monitoring the Future (MTF): MTF is a trend study, that implements cross-sectional nationally representative surveys of high school seniors, collected since 1976 (and for 8th and 10th graders since 1991).  

  1. Strong research question: Did teenage attitudes towards cigarette use shift following the implementation of minimum age cigarette purchasing restrictions? 

  1. MTF questionnaires cover a wide range of topics, including attitudes towards drug use, planned career trajectories, and drug use patterns, making it apt for measuring population average changes and trends over time.  

  1. Weak research question: Do teenage attitudes towards drug use persist into young adulthood? 

  1. MTF is unable to examine long-term outcomes, as surveys collect information only on cross-sectional points in time and don't follow individuals longitudinally.  

  1. Panel Study of Income Dynamics (PSID): PSID is a panel study, a type of longitudinal study design defined as describing cases at two points or more in time. Panel studies differ from cohort studies, which follow cohorts (a group of people selected for their inclusion in a “cohort”, often based on age/year of birth) at often infrequent intervals in that they generally sample from the entire age range, and are used extensively to monitor poverty dynamics, movements into and out of the labor market, and demographic change. 

  1. Strong research question: Are there differences in long-term downstream effects of self-earned income verses spousal earned income on mortality (e.g. does the act of earning income differ from having access to income)? 

  1. PSID includes multiple generations of families, making it well suited to answer questions regarding intergenerational characteristics and life-course exposures over time. 

  1. Weak research question: Are effects of the "healthy immigrant" generalization on mortality mediated through income? 

  1. Although the PSID is designed to be nationally representative, there is little information on immigrants. Furthermore, PSID is subject to reactivity (responses to subsequent questions being affected by prior questions) and retention as participants are repeatedly surveyed.

Re: Week 3 Discussion

by Luis Rodriguez -

Chloe, 

These are great examples of questions that can and cannot be asked using different data sources. I was not familiar with either of these so it is great to learn about more databases, particularly since one of my populations of interest are adolescents. 

Re: Week 3 Discussion

by Maria Glymour -

Chloe,

Great examples of diverse study designs and good examples of strong and weak RQs for each.

Note that there is effectively no difference between panel studies and cohort studies as the term "cohort" is used in epidemiology.  Although a cohort is defined by a common experience, such as birth at a particular date, this is interpreted very broadly in epi. We use cohort to describe any observational study in which a group of people are defined at one point in time and repeatedly assessed over a follow-up period.  Nurses Health Study is a cohort, as are the ARIC and MESA studies that Luis mentioned. PSID could be conceptualized as a cohort with the complication that everyone who ever passes through a PSID family is themselves followed and it includes multiple generations. 

Epidemiologists rarely use the term "panel" study but economists frequently do.  So studies that were started by economists are more likely to be called panels than cohorts.  

I realize there is a lot of stuff on the internet that is not consistent with this, and I don't know if this is because the internet is full of nonsense or because the term "cohort" study is used inconsistently across disciplines. I cannot identify any meaningful difference.