The Health Belief Model (HBM) stands out among !>ocial-psychological models of health-related behavior as the most frequently cited and researched (Wallston and Wallston. 1984). l! is basically a ·value-expectancy' model developed to explain an individual's health actions under conditions of uncertainty (Becker and Maiman. 1975). The perceived value of an outcome and expectation that a given action will result in that outcome are considered to influence behavior (Rosenstock, 1974). According to the HBM. an individual's state of readiness to take action for a health condition is determined by: (I) Its value in terms of perceived susceptibility to the condition and the probable severity of the condition. (2) Its expectancy based on evaluation of the advocated health behavior, its feasibility and its estimated potential benefit in reducing susceptibility and/or severity, weighed against barriers including physical, psychologic and financial. (3) Cues to action that trigger an appropriate health behavior, including internal cues (perception of body states) and external cues (interpersonal interaction and/or mass media communication). Although it is assumed that diverse personality, social. demographic and structural factors (e.g. access to care) can affect a person's health motivation and perceptions. these variables are not construed as directly causal (Becker and Maiman, 1975)