pointed out two defining characteristics
of general health perceptions: (a) they integrate all
the components that come earlier in the model, and (b) they
are subjective in nature. This component is a synthesis of all
the various aspects of health in an overall evaluation. Supporting
this idea is the finding that the strongest and most
consistent predictors of general health perceptions are physiological
processes, symptoms, and functional ability, based
on a review of 39 studies of the general population (Bjorner
et al., 1996). Although general health perceptions are influenced
by the earlier components of the model, they nevertheless
are different from the others. Thus using measures
of other components, such as functioning or symptoms, to
assess general health perceptions is not appropriate. Instead,
this component is most commonly measured with a single
global question to ask people to rate their health on a Likert
scale ranging from poor to excellent. Ratings of general
health perceptions are used both as single-item measures and
items in a battery, as in the SF-36 Health Survey (Ware &
Sherbourne, 1992).