Test 2 Flashcards
Indicates differences in results found in the sample when compared to the population from which the sample was drawn
sampling error
selecting subjects or assigning them to groups in a way that is not impartial.
selection bias
the most important considerations in the sampling strategy
method for selecting subjects/assigning them to groups & the # of subjects studied
The potential participants who meet the definition of the population and are accessible to the researcher
sampling frame
The goal of the selection strategy is to:
prevent bias, support study validity, and enhance credibility of results
___ ___ run the risk of over-representing characteristics that are local to the study
convenience samples
___ ___ ___ can occur when response rates are low are attrition is high
systematic sampling error
When respondents are asked to recruit subsequent subjects
snowball sampling or referral sampling
Guidlines for choosing subjects with a set of characteristics that include major factors important to the research question
inclusion criteria
characteristics that eliminate a potential subject from the study to avoid extraneous effects
exclusion criteria
A technique used in qualitative research in which the subjects are selected because they possess certain characteristics that enhance the credibility of the study
purposeful selection
stages for qualitative sampling strategy:
Identify charactierstics of ideal informants
ID accessible informants
determine settings for recruitment
Approach & invite potential informants
obtain consent
Used when the study requires subjects to have some common characteristic
typical case sampling
used when there is concern that special or outlier cases may skew responses
homogeneoussampl ing
used when the study requires subjects who have an experience in common
criterion sampling
used when the study will benefit from a diversity of characteristics
maximum variation sampling
used to obtain a sample that has extreme target population characteristics
extreme case sampling
used when additional sources of data are needed during grounded theory development
theoretical sampling
A sampling process used in quantitative research in which every member of the available population has an equal chance of being selected for the sample.
probability or random sampling
used when a table of random number is used to select subjects from the sampling frame
simple random sampling
useful when the researcher is unaware of how many individuals will eventually be in the population or when there is an indefinite sampling frame
systematic random sampling
Structured so that imporant characteristics are evenly distributed across all groups. Useful for reducing the probability that a subgroup will be under-represented or over-represented in some way.
Stratified random sampling
The researcher randomly selects entire groups & then randomly selects subjects from only those groups
cluster random sampling
A nonprobability method of selecting a sample that includes subjects who are available conveniently to the researcher.
convenience sampling
occurs when respondents are incentivized for participating or recruiting their peers
respondent-driven sampling
occurs when individuals who seek out a service are recruited into a study
service-based sampling
The definition of the major entity that will be considered a “subject” for analysis
unit of analysis
An analysis that indicates how large a sample is needed to adequately detect a difference in the outcome variable
power
The measurement of the magnitude of the impact of an intervention
effect size
In qualitative studies, sample size is rarely
predetermined
In quantitative studies, the standard for determining sample size adequacy is:
power
Refers to the way subjects are recruited and selected that may limit generalization to all populations
selection effects
The ability to generalize the findings from a research study to other populations, places, and situations.
external validity
A type of external validity where the findings can be generalized and applied to other settings
ecological validity
A type of external validity where the findings can be generalized and applied to other subjects
population validity
The goals of designing a recruitment plan include:
representing the population, recruiting enough subjects to attain power or saturation.
Determination of the quantity of a characteristic that is present, involves assigning of numbers or some other classification
measurement
clearly stated meaning of an abstract idea or concept used by a researcher in a study.
conceptual definition
An explanation of the procedures that must be performed to accurately represent the concepts.
operational definition
data collected directly from the subject for the purose of the research study.
primary data.
instruments used to collect subjective information directly from subjects
psychometric instruments
A scale that uses attitude statements ranked on a 5 point or 7 point scale.
likert scale
a scale with a set of items on a continuum or statements ranging from one extreme to another. Responses are progressive and cumulative
guttman scale
A rating type scale in which respondents mark a location on the scale corresponding to their perception of a phenomenon on a continuum.
visual-analog scale
The diference between the actual attribute and the amount of attibute that was represented by the measure
measurement error
A nonreproducible error that can arise from a variety of factors in measurement
random error
any error that is consistenlty biased; the measure is consistent but not accurate
systematic error
The use of procedures to minimize measurement error associated with physical instruments by objectively verifying that the instrument is measuring a characteristic accurately.
calibration
the degree of reproducibility or the generation of consistent values every time an instrument is used.
precision
the extent to which an instrument is consistent within itself as measured with the alpha coefficient statistic.
internal reliability
the extent to which an instrument is consistent across raters, as measured with a percentage agreement or a kappa statistic
inter-rater reliability
The ability of an instruemnt to consistenlty measure what it is supposed to measure
validity
Involves a subjective judgment about whether a measurement makes sense
Content validity
An outline for determining content validity that includes the analysis of basic content and the assessment objectives
test blueprint
Indicates that a measurement captures the hypothetical basis for the variable
construct validity
The correlation of the instrument to some external manifestation of the characteristic.
criterion-related validity
present when an instrument reflects actual performance
concurrent validity
indicates that a measure can predict future performance
predictive validity
demonstrates the capacity to differentiate those who have a characteristic from those who do not.
discriminant validity
A measure of discriminant validity in the biomedical sciences that indicates an instrument has the capacity to detect disease if it is present.
sensitivity
A measure of discriminant validity that indicates an instrument has the capacity to differentiate when the disease is not prsent
Specificity
A measure that indicates change in the subject’s condition when an intervention is effective
responsiveness
Data collected for other purposes and used in the research study
secondary data
Codes established prior to data collection that include definitions, abbreviations, and a range of possible numerical values for the variables.
codebook
A qualitative data measure that reflects the stability of the information across indivdiuals or over time.
dependability
A qualitative data measure focused in ensuring that the results represent the underlying meaning of the data.
credibility
The confidence that an experimental tx or condition made a difference and that rival explanations were systematically ruled out through study design and control.
internal validity
bias is introduced in research through 3 major areas:
sampling error, treatment effects, measurement error
The rejection of a true null hypothesis; the researcher erroneously draws a conclusion that the intervention had an errect.
type I error
The acceptance of a false hypothesis; the researcher erroneously draws a conclusion that the intervention had no effect
type II error
The magnitude of the impact hat the intervention or variable is expected to have on the outcome
effect size
A threat to internal validity because of events or circumstances that occur during data collection
historical threats
A threat to internal validity becauseo f the changes that occur in subjects that do not happen as a result of the intervention, but rather because time has passed.
maturation
A threat to internal validity due to the familiarity of the subjects with the testing, particularly when retesting is used.
testing
A threat to internal validity because the instrument or data collection procedure has changed in some way
instrumentation
A threat to internal validity because subjects may perform differently when they are aware they are in a study or as a reaction to being treated
placebo effect
A threat to internal validity due to the introduction of bias through selection or composition of comparison groups.
subject selection
The capacity to confidently generalize the results of a study from one group of subjects to another population group.
popoulation validity
A threat to external validity that occurs when subjects react to something because it is novel or new, rather than to the actual treatment or intervention itself.
novelty effect
A threat to external validity due to the interaction with the researcher conducting the study or applying the intervention
experimenter effect
The feasibility of applying qualitative research findings to other samples and other settings
applicability/transferability
The likelihood that qualitative research outcomes or events will happen again given the same circumstances.
replicability
Cross-checking conclusions using multiple data sources, methods, or researchers to study the phenomenon
triangulation
Check the accuracy of the observations and conclusions directly with subjects.
member checking.
The process of explicitly reflecting on and documenting the researcher’s biases.
bracketing
Detailed documentation of sources of information, data, and design decisions related to a qualitative research study.
audit trail
The study of the distribution and determinants of disease within populations or cohorts.
epidemiology
Study conducted by examining a single phenomenon across multiple populations at a single point in time with no intent for follow up
cross-sectional study
A study conducted by following subjects over a period of time, with data collection occurring at prescribed intervals.
longitudinal study
The meticulous descriptive exploration of a single unit of study such as a person, family group, community, or other entity
case study
An investigation using a single case or subject in which baseline data are collected, an intervention is applied, and the responses are tracked over time.
single-subject design
Single-subject designs that continue to measure the response of the individual as the intervention is withdrawn or withdrawn and reinitiated
reversal designs
A design that involves the analysis of two variables to describe the strength and direction of the relationship between them.
correlation study
Research designed to search for variables measured at one point in time that may forecast an outcome that is measured at a different point in time.
prediction study
Tests of association used to determine whether a set of relationships exists in the real world in the way the relationships are hypothesized in the researcher’s model of reality
tests of model fit
A variable that is not measure but is related to each variable in the relationshps and may affect the correlation of the data.
suppressor variable
A condition in which two variables havec an appearance of causality where none exists.
Spurious relationship
The count of instances that an event occurs in a data set
frequency
A calculated count derived from dividing the frequency of an event in a given time period by all possible occurrences of the event during the same time period.
rate
A new variable produced when data from other variables are combined using a simple formula
derived variable
A type of frequency distribution in which variables with different values are plotted in a graph to visualize the shape
histogram
A measure of variability that gives information about the spread of scores around the mean
variance
The most easily interpreted measure of variability of scores around the mean; represents the average amount of variation of data points about the mean
standard deviation
A calculation that produces a number tha depicts the standard deviation relative to the mean.
coefficient of variation
A measure of position that expresses the distance from the eman of a single score in standard terms.
standardized scores
A bell-shaped distribution in which the mean is 0 and a standard deviation is 1
standard normal distribution
A large standard deviation means a ____ variability
small amount of variability
A measuret hat depictst he strength and nature of the relationship between 2 variables
correlational analysis
A graphic presentation that marks the median of the values in the middle of the box and the 25th and 75th percentiles as the lower and upper edges of the box. Indicates the relative position of the data for each group and the spread for comparison
box plot
Types of probability/random sa mpling:
simple random
systematic random
stratified random
cluster random
What is the most common type of sampling?
convenience sampling
Methods for sampling hard to reach populations
speak in native tongue
experience sampling methods
respondent-driven sampling
service based sampling
____ ____ reflects the degree of representativeness of the population & encourages generalizability of the results
response rate
The point in qualitative samples where no new information is being generated
redundancy/saturation
Mutually exclusive
Encompass the total range of answers
Used to allow the best answer for all the options
Sometimes have right and wrong answers
Forced choice
Selecting from only one of two choices
Yield limited information
Difficult to analyze
Use only when other types of questions are not appropriate
Dichotomous questions
used as a (lowerbound) estimate of the reliability of a psychometric test
cronbach’s alpha
stability within instruments
internal reliability
stability among individuals
item-total correlation
Stabilitiy between raters
inter-rater reliability
stability over time
test-retest
Types of criterion-related validity
concurrent
predictive
discriminate
threats to internal validity
History Maturation Testing Instrumentation Treatment effects Selection effects Attrition
Threats to external validity
Selection effects Time History Novelty Experimenter effects
used to determine validity in qualitative research
credibility, trustworthiness, applicability/transferability, replication
Ways to promote the validity of qualitative research
Prolonged or varied field experience Verbatim accounts Triangulation Member checking Bracketing Audit Trails
The purpose of ____ _____ is the exploration and description of phenomena in real life situations.
descriptive research
Level of measurement with categorical data/labels/no mathematical properties
nominal
level of measurement involving categorical data that are ranked
ordinal
Level of measurement involving data ranked with equal intervals
interval
level o measurement involving interval level data that have a true zero
ratio data
measurement example: blue, green, red
nominal
measurement example: low, medium, high
ordinal
measurement example : 1, 2, 3, 4, 5
interval
measurement example: 0, 1, 2, 3, 4, 5
ratio
methods used to summarize data for nominal/ordinal data:
frequency tables, bar charts, relative frequency, pie charts
methods used to summarize interval/ratio data:
measures of central tendency, variability, position, histograms
midpoint of a distribution of values
Stable measure, less affected by extremes
Ordinal, interval, or ratio data
median
The only measure that can be applied to nomial data
Mode
A descriptive ratio that reflects the amount of variation in a data set
coefficient of variation
Describe the relative position of an observation within a distribution
standard scores
