Understanding the medical & social sciences research landscapes
It is helpful to understand the landscape of both the medical & social science disciplines' research design concepts (and how they can overlap) when performing a literature review aimed at answering a bioethical question. Here are a few to be aware of:
The Evidence Hierarchy
It is helpful to see the landscape of study designs before diving into their definitions as they relate to research questions.
The Evidence Hierarchy is one way* to view some (not all) study designs, where they fit in, and the level of evidence they might provide.
Systematic Reviews and Meta-analyses are typically positioned at the top because of the rigorous nature of their methodology in order to answer clinical questions.
*There is much debate over the use of the Evidence Hierarchy in the research community. One of the top reasons for the debate is the lack of fluidity in the structure of the hierarchy and the depiction of quality generally increasing or decreasing based on study type. Please note that this is just one way to view study designs in relation to one another and that quality is subjected to individual studies, their study teams, and the rigor with which the study is conducted.
Social sciences study designs
Study designs in social sciences can take a variety of approaches to answer a research question. It is helpful to categorize these into qualitative and quantitative approaches. Check out how these examples* of methods can be organized and defined below.
|
QUALitative: focus on in-depth understanding of experiences and behaviors |
QUANTitative: rely on numerical data for analysis and statistical inference |
|---|---|
| Interviews: Conversations between a researcher and a participant; can be semi-structured or unstructured and should use open-ended questions to collect detailed perspectives and data. | Descriptive Research: Aims to describe the characteristics of a population or phenomenon usually through the collection of survey data. It answers questions about "what," "where," "when," and "how" without exploring the "why." |
| Ethnography: Where researchers immerse themselves in a culture, group, or community to understand its beliefs, behaviors, and social dynamics from an insider's perspective; data is usually collected over and extended period of time. | Experimental: Often considered the gold standard for establishing a cause-and-effect relationship; involves manipulating an independent variable to see its effect on a dependent variable. Participants are often randomly assigned to a control group (no treatment) and an experimental group (receives treatment). |
| Focus Groups: Small group interview with participants (less than 10) from a target audience. A moderator guides a discussion to gather insights on a specific topic. | Correlational: Investigates the relationship (or association) between two or more variables including the strength and direction of the association. |
| Content Analysis: The review and analysis of existing texts, like public documents, personal diaries, emails, or other artifacts. | Longitudinal: involves collecting numerical data from the same group of people over an extended period (weeks to decades); allows researchers to observe changes and developments within the same individuals over time, rather than comparing different groups at a single point in time. |
| Observation: The researcher observes and records behaviors, interactions, and events in a natural setting. This can include participant observation. | Case-Control: Compares two groups of people: those with the disease under study (cases) and a similar group of people who do not have the disease (controls). Researchers study the histories of the people in each group to learn what factors may be associated with the disease. |
*This is not an all-inclusive list of research designs. Check out the University of Texas Arlington Libraries Quantitative and Qualitative Research guide for more in-depth details about study designs.
Mixed methods Research: Combining both qualitative and quantitative methods within a single study to collect and analyze data. mixed methods approaches provide researchers with more flexibility when attempting to answer their questions.
Clinical study designs
Here are a few study designs with their descriptions as they relate to the concepts in a PICO question and the type of clinical questions they can answer. In each case, a well-conducted SR of all available studies that address a clinical question is better than an individual study.
| Design | Description (P: Population, I: Intervention; O: Outcome) |
|---|---|
| SR / MA | Involve systematic literature searches to identify, appraise, and synthesize all relevant research relative to a specific P, I, or O. |
| RCT | Cohort studies where allocation to treatment and control groups is achieved by a random process. P → I → O(s) |
| Cohort | Begins with a group of people who do not have a condition, takes baseline measurements, then follows them over time to determine whether or not they develop the condition. I → O |
| Case-Controlled | Identify factors that may contribute to an existing medical condition by comparing subjects with that condition (cases) with patients who do not have the condition but are otherwise similar (controls). O → I |
| Case Series | Coherent / consecutive set of cases of a condition which derive from the practice of one or more health care professionals / settings. |
Research question types
Here are the clinical question types addressed above, an example to contextualize each, and the appropriate study design to answer the question.
| Question Type | Example | Study Design for Question* |
|---|---|---|
| Therapy | Is this intervention more effective than another? | RCT |
| Diagnostic Test | How accurate is this diagnostic test? | independent, prospective blind comparison to a gold standard |
| Prognosis | What is the likely outcome, progression, or survival time for this condition? | cohort study → case-control → case series |
| Harm / Etiology | What are the possible causes of this condition or state of affairs? | RCT** → cohort study → case-control → case series |
| Prevention | How to reduce the risk of this disease? | RCT → cohort study → case-control |
*In each case, a well-conducted SR of all available studies that address a clinical question is better than an individual study.
**RCTs can answer questions of harm when studies report adverse events, but these studies are never chosen with intent to cause harm.
Data for bioethical research
Including data findings in your research helps build context related to your topic by revealing prevalence, trends, and trajectories of the problem.
Quick Vocabulary Lesson: Data, Data Set, and Statistics
|
Data - the quantities, characters, or symbols on which operations are performed by a computer, being stored and transmitted in the form of electrical signals and recorded on magnetic, optical, or mechanical recording media (Oxford) A few things to remember about data:
|
|
Data Set - a collection of related sets of information that is composed of separate elements but can be manipulated as a unit by a computer (Oxford) A few things to remember about a data set:
|
|
Statistics - the practice or science of collecting and analyzing numerical data in large quantities, especially for the purpose of inferring proportions in a whole from those in a representative sample (Oxford) A few things to remember about statistics:
|
Finding data - the following resources are great places to find human health related data.
*The US Census Bureau is helpful for local level data as well.