Exam 2 - Chapter 10 Flashcards
define measurement
the process of assigning numbers to concepts, objects, events, or situations using a set of rules
what are the types of measures?
- direct
- indirect
what are the rules of measurement?
promote consistency in measurement methods between different individuals
what do direct measures involve?
determining the value of concrete factors
examples of direct measures
- weight
- BP
- O2 sat
- temperature
what are indirect measures?
these are indicators of a concept that can capture elements of the measurement of an abstract idea
examples of indirect measures
- pain
- depression
- coping
- self-care
- self-esteem
- anxiety levels
- feelings
what are the levels of measurement?
- nominal
- ordinal
- interval
- ratio
what is the purpose of nominal-level measurement?
organize data into categories of defined properties
elements of a nominal-level measurement cannot be rank-ordered
true
categories in a nominal-level measurement differ in quality than quantity
true
what are important characteristics of categories in a nominal-level measurement?
- not orderable
- exclusive
- exhaustive (thorough)
what does ordinal-level measurement entail?
data need to be assigned to categories that can be ranked
interval-level measurement uses scales
true
what is a property of a scale?
it has equal numerical distances between the intervals
why are ordinal data considered to have unequal intervals?
there is no certainty that intervals between ranked categories are equal
what does exclusive mean in categories of data?
each datum fits into only one category
what does exhaustive mean in categories of data?
each datum fit into at least one category
examples of ordinal-level of measurement
- pain scale
- ADLs
- Fall Scale
- Braden Score
what rules do the scales in interval-level measurement follow?
- mutually exclusive, exhaustive, and ranked categories
- representation of a continuum of values
examples of interval-level measurement
- temperature
what is ratio-level measurement?
the highest form of measurement and meets all the rules of other forms of measurement
what are the rules that categories of ordinal-level measurement follow?
- ranked
- exclusive
- exhaustive
what is a distinct rule that only ratio-level measurement follows?
data must have an absolute zero
what are all the rules that categories of ratio-level measurement follows?
- exhaustive
- exclusive
- ranked
- equal intervals
- absolute zero
interval-level measurement has no zero point
true
define measurement error
the difference between the true measure and what is actually measured
define true measure
the ideal perfect measure
what are the types of measurement errors?
- systematic
- random
what is a random measurement error?
measured values and true value have no clear pattern
what is a systematic measurement error?
the variation in measurement values is primarily in the same direction
what is the common cause of random measurement error?
human error
what is the most common cause of systematic measurement error?
the wrong measurement tool was used, despite it working optimally
what does reliability in measurement focus on?
the consistency of a measurement method
which value of correlation coefficient is considered perfect reliability?
1.00
which value of correlation coefficient is considered no reliability?
0.00
what value is the lowest acceptable coefficient for a well-developed measurement tool?
≥ 0.80
what are the types of reliability?
- stability
- equivalence
- homogeneity
what is stability reliability concerned with?
the consistency of repeated measures using the test-retest reliability
what does equivalence reliability compare?
- two versions of the same measurement
- two observers measuring the same event
what are the subtypes of equivalence reliability?
- alternate forms reliability (instruments)
- interrater reliability (observers)
what are physiological measures?
these are measurement methods used to quantify the level of functioning of human beings
which sources of error affect physiological factors?
- environment (temperature)
- user who is operating the equipment
- subject (capacity)
- equipment (calibration)
- interpretation (misinterpretation)
routine physiological measures are assumed to be accurate & precise, but are not always correct
true
what kind of evidence do researchers need to provide when they are using physiological measures?
evidence of the measure’s accuracy, precision, & potential for error
what are the measures that help determine accuracy of screening & diagnostic tests?
- sensitivity
- specificity
- positive predictive value
- negative predictive value
define sensitivity
the proportion of patients with a disease who have a positive screening test
define specificity
proportion of patients without a disease who have a negative screening test
define positive predictive value
the percentage of true-positives who test positive
define negative predictive value
the percentage of true negatives who test negative
what are some examples of conditions that need a test?
- colorectal cancer
- flu
- diabetes
what are the types of physiological measurements?
- physical measurement
- microbiological measurement
what are the types of observational measurements?
- unstructured observation
- structured observation
what are the types of interviews?
- unstructured interview
- structured interview
what do unstructured observations involve?
an interaction to watch the participant perform in a specific setting
what do structured observations entail?
- the researcher carefully defining what they need to observe
- how these observations are going to be quantified
how can researchers structure their observations?
develop a category system for organizing & sorting the behaviors or events being observed
what are the types of scales?
- rating scales
- Likert Scale
- visual analog scales
what is the most common scale?
Likert Scale
what is the data collection process?
the process of acquiring subjects & collecting study data
describe the content of an unstructured interview
it is controlled by the study participants
describe the content of a structured interview
- it is similar to a questionnaire
- responses to questions are carefully designed by the researcher
what is a questionnaire?
a self-report form designed to elicit information through written, verbal, or electronic responses
in which type of study are questionnaires often used?
descriptive study
what is the Likert Scale designed for?
to determine the opinions or attitudes of study subjects
what is the Visual Analog Scale used for?
to measure the strength, magnitude, or intensity of subjective feelings
define administrative data
data collected within clinical agencies by different people in different sites using different methods
