Quantitative Designs in Nursing Research Flashcards
The purpose of research design? And some different types of research(3)
- to aid in the solution of research question; and to maintain control of how data collected
1) basic research- a research question is driven by a researchers curiosity or interest in a theoretical question(ex. Test assumption in nursing theory)
2) applied theory- designed to solve clinical problems rather than to acquire knowledge for knowledges sake(ex. To improve health of particular group of patients)
3) biomedical- lab research with animals; pharmacy
How is a research design chosen?
- usually the state of knowledge in a particular topic dictates the type of research design that is used
- the research problem, purpose, literature review, theoretical framework, and hypotheses should fit together to create a well designed research project
Another purpose of research design? Cont
-the contribution of a study’s find in to evidence based practice is related to the level of evidence provided by the study results
Objectivity of problem conceptualization?
- theoretical framework- used to guide the review or the literature
- review of the literature- provides researcher with knowledge about: what is known about the problem, methods used to study the problem, results, suggestions for future research, if replication of a study is recommended
What is accuracy?
- researcher should choose a design that is consistent with the research problem and one that offers maximum amount of control of variables
- if a problem has not previously been studied using a particular methodology, a pilot study is often conducted to test out whether the research design chosen will actually work with that particular patient population
What is feasibility?
- capability of study to be conducted successfully
- ex) available subjects, timing of research, time required for subjects to participate, costs, and analysis of data
What is control?
- Involves holding the conditions of the study constant
- helps to rule out extraneous or mediating variables that complete with the explanation of the study’s findings
- establishes strict eligibility criteria for the study participants and helps to eliminate bias( on the DV)
How can we establish control?
- use of homogeneous sample
- use of consistent data collection procedures
- manipulation of the IV consistent
- randomization- each member of the population for study has equal access of being selected
Internal and external validity?
- the results of a study must be credible and dependable. So how do we evaluate this?
- internal validity- asks whether the difference or change in DV is a result of the IV under study
- the researcher must be able to rule out other factors or threats that just explain the relationship between the IV and DV
- a number of threads may exist and must be considered by both the researcher, and consumer who is critiquing the study
Threats to internal validity? (6)
1) history- an event that occurs that may affect results or provide another explanation
- ex) researchers studying smoking behaviour of teens
- then federal government launches a big campaign aimed at teens half way through the study
Threats to internal validity?
2) Maturation- refers to a change that occurs over time and is external to the events of the investigation
- includes developmental, biological, and/or psychological processes that occur ex) changes that occur due to death of a spouse, changes in health status, depression
Threats to internal validity?
3) testing- repeated testing with the same instrument may result in a threat to internal validity
- ex. Knowledge test before an info session and then again right after, and then every week for six weeks using same test
Threats to internal validity?
- Instrumentation- calibration of equipment such as thermometer, BP machine, weight scales, glucometer
- can also include techniques/observational data ex. Measurement of waist/hip ratio, size of a bruise or wound
- making changes to a measure that has already been validated
Threats to internal validity
- Mortality- loss of patients in the study after the first measurement
- subjects who dropped out May be different from the group that stayed in study
- also includes loss due to death
Threats to internal validity?
- Selection bias
- need to representative sample for study
- occurs when subjects decide whether they want to be in the study
- ex. Smoking cessation program- only those who are interested in such a program will agree to be in study so this result is selection bias. Major bias problem in clinical research studies
External validity?
- asks: are results generalizable to additional populations and to other sites/conditions? Ex) if you repeated this study in another clinic in another provided would you get the same results?
Threats to external validity(3)?
1) selection bias
- are results generalizable to other populations
- patients at different sites may be very different
- ex. Gender of patients in a study- results may not able to be generalized to all patients if mostly one gender
- muti-site studies help to deal with selection bias
External validity? Threats
- Reactive effects: subjects response to being studied
- ex. Subjects may rate an intervention higher just b/c had more opportunity to interact with a researcher
External validity- threats
- Measurement effects
- administration of a pre-test may sensitize subjects so that answer the post-test differently
- ex- pre-test on nurses attitudes towards HIV patients
- workshop on how nurses are expected to treat HIV patients- measure post-test
- subjects learn from the session what answers are socially acceptable
Experimental designs?
- test cause and effect relationships because they can help to eliminate potential alternative explanations(threats to validity) for the findings
- the validity of conclusions of study depend on how well the researcher have controlled other variables that may further explain the relationships
Types is experimental designs. Three properties**
1) randomization
2) control
3) manipulation
Manipulation of variables? Types
- antecedent variables- factors such as age, stage of disease, gender, health status etc may affect DV
- try to control by patient selection( before study starts)
- intervening variables- occur during course of the study(not part of the study) however, they can effect DV and results of study ex) change in physical, biological or psychological processes that occur as part of life
Types is experimental design(3)
1) true or classic experimental design
2) Solomon four-group experimental design
3) after-only experimental design
1) true or classic experimental design
2) Solomon four-group experimental design
3) after-only experimental design
key to design models- p. 221
R- random assignment O-observation via data collection on DV O1- specifies pretest data collection O2- post test data collection X- intervention