This short course will
provide an exposition on
health measurement scales –
Patient-reported outcomes (PROs) is an umbrella term that includes a whole host of
subjective outcomes such as pain, fatigue, depression, aspects of well-being (e.g., physical, functional,
psychological), treatment satisfaction, health-related quality of life, and physical symptoms such as
nausea and vomiting. PROs are often relevant in studying a variety of conditions—including pain,
erectile dysfunction, fatigue, migraine, mental functioning, physical functioning, and depression—that
cannot be assessed adequately without a patient’s evaluation and whose key questions require patient’s
input on the impact of a disease or a treatment. To be useful to patients and other decision makers (e.g.,
clinicians, researchers, pharmaceutical companies, regulatory agencies, reimbursement authorities),
who are stakeholders in medical care, a PRO must undergo a validation process to confirm that it
measures what it is intended to measure reliably and accurately.
Some key elements in the development of a patient-reported outcome (PRO) measure will be noted.
The core topics of validity and reliability of a PRO measure will be discussed. Exploratory factor analysis
and confirmatory factor analysis, techniques to understand the underlying structure of a PRO measure,
will be described. The topic of mediation modeling will be presented as a way to identify and explain the
mechanism that underlies an observed relationship between an independent variable and a dependent
variable via the inclusion of a third variable, known as a mediator variable. Approaches to interpret PRO
results will be elucidated in order to make results useful and meaningful. Other topics such as item
response theory and longitudinal analysis will be considered if time permits. Illustrations will be
provided mainly through real-life examples and also through simulated examples using SAS.