Numerous definitions of health exist and, in this report, we have adopted the following:
“Health is a human condition with physical, social and psychological dimensions, each
characterized on a continuum with positive and negative poles. Positive health is associated
with a capacity to enjoy life and to withstand challenges; it is not merely the absence of
disease. Negative health is associated with morbidity, and in the extreme, with premature
mortality” (10, p.100).
Health-related quality of life is an individual's overall sense of well being and includes
such factors as pain, mood, energy level, family and social interactions, sexual function,
ability to work, and ability to keep up with routine daily activities
Explanation:
Absolute risk. The percentage of subjects in a group that experiences a discrete negative
outcome, such as death or hospital admission.
Case-control study. A type of epidemiological study design in which subjects are selected
based on the presence or absence of a specific outcome of interest, such as cancer or
diabetes. The individual’s past physical activity practices are assessed, and the association
between past physical activity and presence of the outcome is determined.
Case report. This includes single case reports of individual patients and published case
series.
Confidence interval. When relative risk (see definition below) is calculated, one can also
calculate a confidence interval, or a band of uncertainty, around the estimate of the relative
risk. Typically, 95% confidence intervals are used in epidemiological studies. For example, if
the estimated relative risk for colon cancer associated with physical activity, compared with
inactivity, is 0.5 with a 95% confidence interval of 0.3 to 0.8, this means that we are 95%
certain that the true estimate of the relative risk lies between 0.3 and 0.8.
Cross-sectional study. Studies that compare and evaluate specific groups or populations at
a single point in time.
Observational studies. Studies in which outcomes are measured but no attempt is made to
change the outcome. The two most commonly used designs for observational studies are
case-control studies and prospective cohort studies.
