Week 8 Flashcards
Quantitative research methodology emanates from which nursing research paradigm?
Positivism/post-positivism
Define validity
Validity - the quality of being logically or factually sound; soundness or cogency.
Define setting
Setting - the place or type of surroundings where an event takes place
Define variable
Able to be changed or adapted. Measurable characteristic that varies among subjects (research is conducted because this variance occurs).
What are the two purposes of research design?
- To aid in the solution of research problems
- Maintain ‘control’
Which research methodology has been the predominant ‘biomedical’ focus?
Quantitative methodology
Define quantitative research
Quantitative research is a research strategy that focuses on quantifying the collection and analysis of data. It is a formal, object, systematic process in which numerical (empirical) data are obtained to describe, compare, and predict phenomena.
Describe characteristics of quantitative research
-Objective (etic)
-logical
-experimental/scientific processes to:
1. compare (variables, groups)
2. Infer causation (one thing causes another thing)
3. Predict outcomes
Where are research designs located in a research paper?
The method section
What are the types of variables?
- Independent variable (IV)
- Dependent variable (DV)
- Extraneous variable or covariate
What is the independent variable?
a variable (often denoted by x ) whose variation does not depend on that of another.
Interventions or presumed cause (ex. salt intake or self-care symptom management).
What is the dependent variable?
a variable (often denoted by y ) whose value depends on that of another.
Outcome or presumed effect (ex. blood pressure reading or quality of life).
What is an extraneous variable or covariate?
Any variable that you’re not investigating that can potentially affect the outcomes of your research study. A variable that is not the independent or dependent; alternative or other possible causes (ex. severity of illness).
Control refers to measures used to what?
- decrease error and the influence of unwanted “extraneous” variables
- increase probability that study findings are an accurate reflection of reality, and reflect true relationship among IVs & DVs.
What is the first (and second) rule of quantitative research?
Do no run an uncontrolled study
Define control
Control is defined as the measures that the researcher uses to hold the conditions of the study uniform and avoid possible influence of bias (distortion of the results) on the dependent variable or outcome.
Control - a group or individual used as a standard of comparison for checking the results of a survey or experiment.
What are some ways to control for extraneous variables?
-Utilize a homogeneous sample (e.g., similar age, gender, length of time smoking, amount smokes).
-Random assignment to groups (randomization)
-Consistent data-collection procedure
-Minimize threats to internal validity
-Using experimental design (manipulation of independent variable)
-Statistical manipulation
How does randomization help in research?
Randomization helps to equal bias and aids in attainment of a representative sample.
What is a natural setting?
A setting that is uncontrolled; real life situation.
What is a partially controlled setting?
A setting that is manipulated or modified in some way.
What is a highly controlled setting?
An artificial environment for sole purpose of doing research.
What are the 3 types of settings for research?
- Natural setting
- Partially controlled
- Highly controlled
Define internal validity
Internal validity is the degree of confidence that the causal relationship you are testing is not influenced by other factors or variables.
Are the changes in the outcome (dependent variable) due to a change in the exposure (independent variable). Goal: rule out other explanations.
What is external validity?
External validity concerns the generalizability of an investigation’s findings to additional populations and to other environmental conditions and hence internal validity must be established prior to establishing external validity.
Are the findings generalizable to other populations/settings?
Goal: useful beyond participants/setting.
Why is internal validity important?
- focus on accuracy and a strong research method
- controls extraneous variables
- eliminates alternative explanations
If a study shows a ______ _____ of internal validity, then we can conclude we have ______ evidence of causality.
high degree; strong
If there is a lack of internal validity, the study cannot have what?
external validity
If a study has a low internal validity, then we must conclude that we have what?
little or no evidence of causality
List the main threats to internal validity
- selection bias (if participants’ characteristics raise possible alternate explanation)
- instrumentation (inter-rater differences, failure of instrument)
- history (if event occurs simultaneously with intervention/situation that affects outcome)
- maturation (natural changes during study that affect outcome/DV)
- testing (act of being tested once affects outcome of next test)
- mortality (attrition; differential loss from groups)
Define selection bias
Selection bias is the bias introduced by the selection of individuals, groups, or data for analysis in such a way that proper randomization is not achieved, thereby failing to ensure that the sample obtained is representative of the population intended to be analyzed.
Threats to external validity compromise our confidence in what?
stating whether the study’s results are applicable to other groups
List some of the main threats to external validity
- Selection effects (if study sample does not represent the population of interest)
- Reactivity (natural reactions to being studied; Hawthorne effect)
- Measurement effects (actual act of being tested affects outcome)
What study designs control threats to validity?
- experimental (eg., randomized control trial (RCT); gold standard; control most threats)
- quasi-experimental (controls some threats)
- non-experimental (may control some threats)
- descriptive (may control some threats)
Define mortality/attrition
Mortality or attrition is the loss of study participants from the first data-collection point (pretest) to the second data-collection point (posttest). If the participants who remain in the study are not similar to those who dropped out, the results could be affected.
Summarize the threats to validity
INTERNAL VALIDITY
History threats
Maturation effects
Testing effects
Instrumentation threats
Mortality (attrition)
Selection bias
EXTERNAL VALIDITY
Selection effects
Reactive effects
Measurement effects
What is randomization?
Random assignment to groups (internal validity issue) - equal extraneous variables in both groups
How?
- Random numbers table
- Computer generated randomized numbers
- Coin flipping
