Module 2 Flashcards
Study Paradigms, and Study Designs
What are paradigms?
Systems of beliefs and practices that influence how researchers select both the questions to study and the methods they use to study them
What are the 3 paradigms explored within the context of health research?
positivist, constructivist, and realist
What is ontology?
Philosophy of existence and the assumption and beliefs that we hold about the nature of being and existence
What is epistemology?
Branch of philosophy concerned with determining what can be known and how it can be known
What are the 2 theories of knowledge acquisition in this class?
Representationalism
Subjectivism
What is methodology?
Strategic approach to the production of date: how we gain knowledge of what exists
What are the 3 types of methodologies in this class?
Quantitative, Qualitative and Mixed
What is the acronym to help remember what/how to contrast research paradigms
POEM Paradigms Ontology Epistemology Methodology
Using POEM, describe the positivist paradigm
P = Positivist O = Realist E= Representational M = Quantitative
Give an example of a positivist paradigm
Seeking to understand the relative burden to society from different disease using national health surveys
Using POEM, describe the constructivist paradigm
P = Constructivist O = Relativist E = Subjectivist M = Qualitative
Give an example of Constructivist paradigm
Seeking to understand the burden from different disease using in-depth interviews with select patients and their families
Describe the positivist paradigm in sentences
Believes there is an objective reality (realist O) and that symbols can be used to described and explain reality (representational E). Rely on analysis of numbers, hypothesis generation and testing, and experimental designs (quantitative M)
Describe the constructivist paradigm in sentences
Believes that reality is constructed intersubjectively through the meanings and understandings developed socially and experientially (relativist O), we cannot separate ourselves from what we know (subjectivist E). Analyze words or behaviours where meanings emerge from the research process through naturalistic methods (qualitative M)
Describe the realist paradigm in sentences
Believes that there is an objective reality but that our ability to know reality is imperfect, we can only know reality from our own perspective of it (realist O). We cannot separate ourselves from what we know (subjectivist E), but objectivity remains ideal. Research is seen as an opportunity to discover rather than testing hypotheses. Natural settings are favoured over laboratory giving priority to situation and contextual data (Mixed M)
Using POEM, describe the realist paradigm
P= realist
O= realist
E = Subjectivist
M=Mixed (both quantitative and qualitative)
Give an example of a realist paradigm
Seeking to understand the relative burden to individuals and society from different disease using population health survey data combined with in-depth interviews with select patients and their families
What are the 3 founding principles of experimental studies?
- Randomization
- Local control
- Replication
What is randomization?
Assign subjects randomly to study or control group. It ensure study group and control groups are as similar as possible and accounts for known and unknown factors that may affect the outcome
What is local control?
refers to the practices and techniques used to ensure the intervention is applied uniformly and under standard conditions
What is replication?
Repetition of the experiment on many experimental units is needed to provide an estimate of experimental error. Number of replication is the sample size
What is the goal of experimental studies?
Seek to introduce a factor or change and rule out alternative causes for the resulting observation, leaving only the actual factor as the real cause
When can experimental studies be conducted?
When ethically feasible. Benefits must outweigh the risks
What are the 3 components of laboratory based research?
- basic research
- preclinical studies
- experimental
What is basic research?
It is discovery based, focuses on developing theories regarding natural phenomena and processes. Purpose is to enrich scientific knowledge (no real-world applications)
EX: Characterize how vascular endothelial cells in culture respond to high concentration of stress hormones
What are preclinical studies
Experimental studies using cell cultures or animals to monitor effects of an intervention of treatment before it is tested in humans. Focuses on evaluating the effectiveness and safety of a potential treatment for humans
EX: Measuring toxicity of a new drug in animal models
What are the categories of basic and preclinical research?
- biochemistry research
- Cell culture-based research
- animal model-based research
What are 2 types of basic research?
Biochemistry
some cell-based research
what are 2 types of preclinical research?
Animal model research and some cell-based research
What is biochemistry research?
Study of the structure and function of biological molecules such as proteins, nucleic acids, carbohydrates, and lipids
What is cell culture-based research?
Study of the behaviour of cells grown under controlled conditions
What is animal model-based research
Use of non-human animals in experiment to seek to control the variables that affect the behaviours or biological system under study
What are the 2 types of trial in experimental research with humans?
- Prevention trial
- Therapeutic trial
What is the goal of a prevention trial?
Assess whether an intervention/treatment may reduce the occurrence of disease in healthy individuals or groups
What is the goal of a therapeutic trial ?
Evaluate new treatments for an existing disease with the intention of curing the disease or improving quality of life. Most experimental research on humans focuses on therapeutic trials
What is a randomized controlled trial?
Intervention study in which people are allocated randomly to receive one of several clinical interventions.
Done on individuals
What is a group trial?
Intervention study in which groups of individuals are assigned to one of several interventions. This deisng is used when the intervention to be evaluated operates at a group level, manipulates the physical or social environment, or cannot be delivered to individuals
ex: best approach to care provision by surgical residents
What are observational studies?
Test hypotheses but does not control the study conditions. Researcher collects information about exposure/independent variables and outcomes/dependent variables to identify areas for further study or to draw inferences about relationships. Without randomization, alternate explanations for any observed association need to be considered
What are the 2 types of observational studies?
Analytic
Descriptive
What are the 4 types of Analytics studies?
- Cohort
- Case-control
- Analytic cross-sectional
- analytic ecological
What is a cohort study?
Researcher selects a group of people with different levels of exposure and follows them through time to see what happens to them. Must all be free of the outcome at the outset
What are the 2 types of cohort studies?
retrospective or prospective
What is a prospective cohort study?
A cohort is created based on current or past exposure and followed into the future to determine if the outcome develops
What is retrospective cohort study?
Historical cohort is constructed using past record. Exposure status is assigned based on information recorded in the past. Cohort is “followed” into the present or more recent past to determine outcome status
What is a case-control study?
A group of cases (those with outcome) is selected and compared to a group of controls (those without the outcome). Past exposure information is collected for both groups
What is an analytic cross-sectional study?
Exploratory study where the exposure and outcome for each individual are measure at the same point in time or during a brief period of time. It also intends to test a hypothesis
What is an analytic ecological study?
Units of analysis are groups (not individuals). Summary measures (average or proportions) of exposure and outcome for the groups are analyzed. It also intends to test hypothesis
What are the 2 types of descriptive studies?
Descriptive cross-sectional
Descriptive ecological
What is a descriptive cross-sectional study?
Exploratory study where the exposure and outcome for each individual are measure at the same point in time or during a brief period of time
What is a descriptive Ecological study?
Units of analysis are groups (not individuals). Summary measures (average or proportions) of exposure and outcome for the groups are analyzed
What is the main difference between observational and experimental study designs?
In experimental studies there is an intervention or treatment that is controlled by investigators, whereas in observational studies the researchers do not modify or control the participants’ activity
What is the purpose of biochemistry research design?
Identify the structure and function of biological molecules related to disease
What is the purpose of cell culture-based research design?
Determine the behaviour of cells exposed to controlled treatments
What is the purpose of animal model-based research design?
Determine the behaviour of biological systems exposed to controlled treatments
What is the purpose of randomized controlled trial research design?
Identify preventive or therapeutic effects in INDIVIDUAL humans
What is the purpose of group trial research design?
Identify preventive or therapeutic effects in GROUPS humans
What is the purpose of Prospective cohort research design?
Identify new disease in those exposed vs not exposed by following them in time
What is the purpose of retrospective cohort research design?
Identify new disease in those exposed vs not exposed by relying on past record of exposure
What is the purpose of case-control research design?
Identify past exposures in cases vs controls
What is the purpose of cross-sectional research design?
Identify exposure and/or diseases at a point in time
What is the purpose of ecological research design?
Identify difference among groups
What are the 3 main types of data sources in quantitative health research?
- Observation/measurement
eg: blood pressure - Surveys/interviews
- Clinical or administrative data
eg: indicators of community violence
What is Probability?
Measure of the likelihood that an event will occur
What is inference?
Gaining information about a population based on data collected from a sample
What are the 2 approaches in dealing with random error?
- Hypothesis testing
- Confidence intervals
What are the steps to hypothesis testing?
- Formulate null hypothesis
- Calculate probability of null hypothesis being true. If probability <5% then we can reject it (not with certainty just unlikely)
What is a type I error?
When the statistical test is significant = we reject the null hypothesis, but the null hypothesis is true. Probability of making this error is given by p-value, or alpha
What is a type II error
Statistical test is insignificant = we do not reject null hypothesis, but null hypothesis is false. Probability of making this error is given by beta
What is statistical power?
Probability of rejecting a null hypothesis when it is false. Power of a study is its ability to show what you’re looking to find
What are the 3 components that affect statistical power?
1- sample size
2- Effect size/ estimate
3- alpha
How does sample size affect statistical power?
The larger the sample size, the greater the power of the study (Law of large numbers)
How does effect size/estimate affect statistical power?
More extreme the expected finding, the easier it will be to find with a given sample size
How does alpha affect statistical power?
Probability at which the null hypothesis will be rejected when it is true, conventionally set at 5%. The higher we set alpha the less likely we will reject the null hypothesis when it is false
What are confidence intervals?
Define a range of plausible values for true population parameters, based on a desired level of confidence. Consists of 2 numbers called confidence limits, thus the confidence interval comprises all values between the lower and upper confidence limit
What provides a measure of how precise the estimate is?
width of confidence interval
narrow = more precise
How is precision related to standard error?
Precision is inversely related to standard error.
Standard error is dependent on sample size; therefore, as sample size increases, standard error decreases and precision increases
What test will be used if the data are categorical?
chi-squared
What tests will be used when data are continuous?
T-test or analysis of variance
What are the 4 types of qualitative research designs?
- Case study
- Ethnography
- Grounded theory
- Phenomenology
What is a case-study?
in-depth analysis of people, events, and relationships bound together by some unifying factor. Do not have to be individually focused. Typically rely on multiple source of data to develop a comprehensive understanding – not inherently qualitative, can rely on ‘numbers’ or both words and numbers
What is ethnography?
Systematic study of the shared patterns of groups of people located in the same place of in frequent contact. Subject is the group or its culture. Observes society from the point of view of the group
What is grounded theory?
Go back and forth between data collection and analysis such that interpretations are continually derived from raw data. The intent is to collect and analyze data to develop or generate an initial theory that informs the subsequent data collection and analysis
Comparative process between finding and theory until “saturation” (point at which there are no new ideas and insights emerging from the data)
What is phenomenology?
Concerned with investigating, describing, and understanding phenomena as they are experienced. Requires researched to suspend their beliefs in the objective existence of the phenomenon. It relies on reflection of lived experience of the participants
What are the 4 types of data sources in qualitative health research?
- observataion
- analyzing texts/documents
- interviews
- recording/transcribing
What is a critical discourse analysis?
Study of a group ideas or patterned way of thinking, which can be identified in textual and verbal communications, and can be located in wider social structures
What are semi-structured interviews?
Interview where interviewer relies on an interview guide - a list of questions and topics that need to be covered (usually in a particular order) - allowing for divergence on a topic when research feels its appropriate
What is coding analysis?
Chunking the data (which is normally in open forms) and naming those chunks
What are 3 approaches to qualitative studies data analysis
- coding
- identifying themes
- searching for meaning
What is saturation in qualitative studies?
Point were additional data does not provide new information
Functions of both richness (number and variety of data sources) and thickness (depth of the information the data provide)
What are the 2 types of saturation&
- descriptive
- theoretical
What is descriptive saturation?
No new codes, categories, or themes emerge from the data analysis
What is theoretical saturation?
Data fully explain how codes, categories, and themes interconnect
How could a qualitative approach enhance health research?
- explores new concept
- explores subjective experience in health
- induces meaning of phenomena
- allows for holistic perspective that considers social and cultural dimension of health
What are 4 characteristics of mixed methods research study
- focuses on research questions that call for real-life contextual understandings, multi-level perspectives, and cultural influences
- Employs rigorous quantitative research assessing magnitude and frequency of constructs and rigorous qualitative research exploring the meaning and understand of constructs
- answers questions that cannot be adequately answered by one approach thus, drawing on the strengths of each
- frames the invertigation within philosophical and theoretical positions
What are the 2 major categories of mixed methods?
sequential (Qualitative & quantitative data collected one after the other)
concurrent (quantitative and qualitative data collected at the same time)
What are the 2 types of sequential mixed method designs
sequential explanatory
sequential exploratory
What are the 2 types of concurrent mixed methods designs?
concurrent triangulation
concurrent nested
What is the sequential explanatory design?
First quantitative data collection and analyses are completed THEN qualitative data collection is completed
- Provides context or more in-depth understanding of a quantitative study result
- useful before attempting to change practice based on statistical finding
What is the sequential exploratory design?
Qualitative data collection and analyses is done firth, then quantitative data collection and analyses are completed.
- used to explore a phenomenon
- useful when developing and testing a new instrument
What is the concurrent triangulation design?
Interpretation of the data is done together and no one aspect takes priority over the other.
- used to confirm, cross-validate, or corroborate findings from each paradigm of the study
What is the concurrent nested design?
On paradigm takes priority over the other.
-used when 2 methods answer different questions or the same question at different levels
What are the four pillars of health research as set by the Canadian Institute of Health Research (CIHR)?
- biomedical
- clinical
- social/ cultural/environmental
- health services and systems
Describe biomedical research?
- discovery-based
- often starting point for clinical research
- Laboratory based (observe cells, enzymes, DNA, disease causing agents, new drug development)
- Relies on basic and preclinical experimental designs
Describe clinical research
- Focuses on causes, diagnosis, treatment, and prevention of illness in individuals
- typically done in hospitals or clinics
- often requires patient participation
- Includes randomized controlled trials and / or observational study designs
Describe social/ cultural/environmental /population health
- concerned with various factors that affect the health of populations
- community trials, quantitative observational design, qualitative designs, and mixed methods design
Describe health services /systems research
- Examines how people get access to healthcare, how much care costs, and what happens to patients as a result of this care
- Community trials, quantitative observational design, qualitative designs, and mixed methods design
