Validity
A term that reflects a solid foundation or justification for bringing the
intended results. In the case of assessment, validity means the degree to
which a measurement instrument truly measures what it is intended to
measure. The establishment of validity is the first priority in developing
any form of assessment. Without it, all other attributes are of little
consequence.
The assessment instrument should accurately represent the skills or
characteristics it is designed to measure. Validity may be characterized
in these four ways - content, concurrent, predictive or criterion-related
validity:
Content validity is the one of
greatest concern to teachers as the test must contain a representative
sampling of the subject matter the student is expected to have learned.
This sampling must be representative and should cross several categories
of competence, a range of patient problems and a list of technical
skills. Valid clinical examination should assess the components of
clinical competence, including the ability to obtain from the patient a
detailed and relevant history; carry out a physical examination of the
patient; identify the patient's problems from the information obtained
and reach a differential diagnosis; identify the appropriate
investigations; interpret the results of the investigations; recommend
and undertake appropriate management including patient education.
Concurrent validity considers
the degree to which a measurement instrument produces the same results
as another accepted or proven instrument which measures the same
parameters.
Predictive validity examines the degree to which a measure
accurately predicts expected outcomes; for instance, a measure of
attitudes toward preventive care should correlate significantly with
preventive care behaviors.
Criterion-related validity includes concurrent validity as well
as predictive validity.
Value
A term referring to what people believe in, or what they consider
important about the way they live. Values influence behavior and culture
as persons, groups and communities. Values therefore are an important
determinant of individual and community health. They are, however,
difficult to measure objectively.
Variable
A quantity, attribute, phenomenon or event that may assume any one of a
set of values:
Independent variable refers to
a characteristic being observed or measured that is thought to influence
an event or manifestation (the dependent variable) within the defined
area of relationships under study. In medical education, it is a factor
that could explain or predict the curriculum's outcomes such as the
curriculum itself, previous or concurrent training, environmental
factors.
Dependent variable is a manifestation or outcome whose
variation we seek to explain or account for the influence of independent
variables. It can be a program outcome, such as knowledge or skill
attainment, real-life performance, and clinical outcomes.
It is prudent to focus on a few dependent
variables that are most relevant to the main evaluation questions and
similarly, to focus on the independent variables that are most likely to
be related to the curriculum's outcomes.