PROs Flashcards
significance of PROs
measures QOL instead of just disease markers
reasons PRO labeling may not be approved
study design
validity of PRO measures
no statistical/clinical difference
excessive missing data
QoL vs HRQoL
QoL: all dimensions that affect people’s well-being, satisfaction, and happiness: including housing, income, occupation
HRQoL: aspects of life contributed to illness & its consequences of therapy: including functional status, physiologic status, perceptions of well being and general life satisfaction
direct vs indirect measures of health
direct: vision, hearing, pain, mobility
indirect: self-care, usual activities, interpersonal relations, social functioning, participation
different ways to scale survey responses
categorical judgment
continuous judgment
what is categorical judgment
results in a nominal scale of measurement (yes/no?)
what is continuous judgment
direct estimation method; visual analogue scale or likert scale (agree-disagree continuum)
what is pretesting
use about 20 patients, analysis of results to assure understanding
reliability vs validity
reliability: the extent to which the measure yields the same number or score
validity: the degree which the measure reflects what it is supposed to measure rather than something else
types of reliability
inter-rater
intra-rater
internal consistency
what is inter-rater reliability
agreement between different observers, refers to a comparison of scores assigned to the same target by two or more raters
what is intra-rater reliability
when you administer the same instrument to the same patient at a different point in time
what is internal consistency?
more than one item addressing same dimension/domain
measured by cronbach’s alpha (correlation among items)
types of validity
content validity
criterion-related validity
construct validity
what is content validity
judges whether the instrument samples all the relevant or important content or domains
what is criterion-related validity
does the measure correlate highly with the gold standard
what is construct validity
do the measures correlate with measures of other variables in hypothesized ways?
what does construct validity depend on
convergence (correlation) between different measures and discriminality (differences) between measures
ways to administer survey
face to face interview
telephone questionnaire
mailed questionnaire
computer assisted
online
generic vs specific health-related instruments
generic: designed to assess QoL for different diseases
specific: designed to assess a specific disease, patient population, function, or condition (ex asthma, children)
length/complexity in general vs specific instruments
general is longer and more complex
thus has lower responsiveness
transformation of QoL score formula
transformed scale= [(actual raw score-lowest possible score)/possible raw score range] x 100
