Research Design Flashcards
What is a theory ?
A general principle or body of principles offered to explain a phenomenon.
Like Dalton’s atomic theory or Einsteins theory of relativity
Range of nursing theories
Grand theories
Broadest scope, most abstract
Apply to all nursing activities
Mid-range theories
Narrower in scope
Bridge between grand theories & practice
Practice theories
Most narrow scope & least abstract
Jean Watson’s Caring Science Theory
Really looks into caring and what it consists of and its role in nursing
- read on if you desire
Caring can be effectively demonstrated & practiced only interpersonally.
Caring consists of carative factors that result in the satisfaction of certain human needs.
Effective caring promotes health & individual or family growth.
Caring responses accept a person not only as he or she is now but as what he or she may become.
A caring environment is one that offers the development of potential while allowing the person to choose the best action for himself or herself at a given point in time.
Caring is more “ healthogenic” than is curing. A science of caring is complementary to the science of curing.
The practice of caring is central to nursing.
Conceptual Models
Represent a less formal attempt to explain phenomena than theories
Deal with abstractions, assembled in a coherent scheme
Just understand that implicitly or explicitly, studies should have a ____________ or ______________ framework.
theoretical; conceptual
What is the caveat with nursing theories ?
Nursing “Grand Theories” evolved from efforts to establish nursing as a profession, separate from medicine.
Difficult to empirically test the aspirational, abstract grand theories, so less relevance to evidence-based practice.
From a population a portion of the population is selected to represent the entire population …. what is this called ?
Sampling
Eligibility criteria include
inclusion and exclusion criteria, specific characteristics that defines the population
What is a strata ?
Subpopulations of a population - such as male and female
What is the target population
The entire population of interest
What is a representative population ?
A sample whose key characteristics closely approximate those of the target population—a sampling goal in quantitative research
Representative samples are more easily achieved with …..
Probability sampling
Homogeneous populations
Larger samples
What is sampling bias ?
The systematic over- or under-representation of segments of the population on key variables when the sample is not representative
What is a sampling error?
Differences between sample values and population values
E.g. population mean age = 65.6 yrs, sample mean age = 59.2 yrs
Difference between probability sampling and non probability sampling …..
One involves random selection of elements with each having an equal, independent chance of being selected
The other does not involve random selection of elements
Types of nonprobability sampling
Convenience sampling
Snowball (network) sampling
Quota sampling
Purposive sampling
Convenience sampling involves
really whatever is most accessible and conveniently available
Most widely used approach by quantitative researchers
Most vulnerable to sampling biases
Snowball Sampling
Referrals from other people already in a sample
Used to identify people with distinctive characteristics
Used by both quantitative and qualitative researchers; more common in qualitative
Quota Sampling
Convenience sampling within specified strata of the population
Enhances representativeness of sample
Infrequently used, despite being a fairly easy method of enhancing representativeness
Consecutive sampling involves ….
COME, LETS GO, EVERYONE INSIDE, everyone one who is here!!!!
Involves taking all of the people from an accessible population who meet the eligibility criteria over a specific time interval, or for a specified sample size
A strong nonprobability approach for “rolling enrollment” type accessible populations
Risk of bias low unless there are seasonal or temporal fluctuations
Purposive (Judgemental ) Sampling
Sample members are hand-picked by researcher to achieve certain goals
Used more often by qualitative than quantitative researchers
Can be used in quantitative studies to select experts or to achieve other goals
Types of Probability Sampling
Simple random sampling
Stratified random sampling
Cluster (multistage) sampling
Systematic sampling
Simple Random sampling
Uses a sampling frame – a list of all population elements
Involves random selection of elements from the sampling frame
Example- a list of all households in Montgomery County - then 500 households are randomly selected
Stratified Sampling
Population is first divided into strata, then random selection is done from the stratified sampling frames
Enhances representativeness
Can sample proportionately or disproportionately from the strata
Cluster (Multistage) Sampling
Successive random sampling of units from larger to smaller units (e.g., states, then zip codes, then households)
Widely used in national surveys
Larger sampling error than in simple random sampling, but more efficient
Sample size adequacy is a key determinant of ___________ in quantitative research.
Sample size needs can and should be estimated through ________ for studies seeking causal inference.
sample quality; power analysis
The big question of data collection ?
do I collect new data specifically for research purposes or do i collect existing data (historical data, records, existing data set)
Major types of data collection methods ?
Self report; observation; biophysiologic measures
major considerations in choosing the data collection approach ….
Do you want more open-ended data or more objective, quantifiable data? How obtrusive is the method?
Structured self reports can be either
Interview schedule
Questions are prespecified but asked orally.
Either face-to-face or by telephone
Questionnaire
Questions prespecified in written form, to be self-administered by respondents
Advantages of Questionnaires (compared with interviews)
Lower costs
Possibility of anonymity, greater privacy
Lack of interviewer bias
Advantages of Interviews (Compared with Questionnaires)
Higher response rates
Appropriate for more diverse audiences
Opportunities to clarify questions or to determine comprehension
Opportunity to collect supplementary data through observation
What are scales used for ?
used to make fine quantitative discriminations among people with different attitudes, perceptions, traits
The Likert Scale is an example - Consist of several declarative statements (items) expressing viewpoints
Responses are on an agree/disagree continuum (usually 5 or 7 response options).
Responses to items are summed to compute a total scale score.
Semantic Differential Scores - Require ratings of various concepts
Rating scales involve bipolar adjective pairs, with 7-point ratings.
Ratings for each dimension are summed to compute a total score for each concept.
Visual Analog scale does what ?
measures subjective experiences (pain, nausea) on a straight line measuring 100 mm
Response set biases
Biases reflecting the tendency of some people to respond to items in characteristic ways, independently of item content
Observational Rating Scales
Ratings are on a descriptive continuum, typically bipolar
Ratings can occur:
at specific intervals
upon the occurrence of certain events
after an observational session (global ratings)
Evaluation of Observational Methods
Excellent method for capturing many clinical phenomena and behaviors
Potential problem of reactivity when people are aware that they are being observed
Risk of observational biases—factors that can interfere with objective observation
Evaluation of Self Report Methods
Strong on directness
Allows access to information otherwise not available to researchers
But can we be sure participants actually feel or act the way they say they do?
Difference between in vivo measurements and in vitro biophysiologic measurements
In vivo measurements occur on or within organisms body (blood pressure)
In vitro is performed outside the organisms body
Evaluation of biophysiologic measures
Strong on accuracy, objectivity, validity, and precision
May or may not be cost-effective for nurse researchers
Advanced skills may be needed for interpretation.
What is a psychometric assessment ?
What are the key criteria ?
an evaluation of the quality of a measuring instrument.
Key criteria in a psychometric assessment:
Reliability
Validity
An experimental research design contains what?
Intervention - Randomization - Control
Quasi Experimental
Intervention
but missing randomization and control
Nonexperimental
No intervention
Observational or descriptive
may have random sampling- but this is not the same as random assignment
Within subjects design - what is it ?
The same people in the experiment are compared at different times or under different conditions
Between subjects design
Different people are compared
Group A subjects take actual study drug
Group B subjects take placebo