others, 2005; Yzer, 2007). For example, in a study of adults over age forty, McLallen
and Fishbein found colonoscopy intention to be almost completely under normative
control, whereas exercise intention was influenced by both attitudes and perceived
control (Fishbein and Cappella, 2006). Similarly, a behavior may be under attitudi-
nal control in one population but under normative control in another population (Fishbein, 1990, Fishbein, von Haeften, and Appleyard, 2001). Our research found that
condom use with a main partner is primarily under normative control for female injecting drug users but influenced by attitude, norm, and perceived control for females
who do not inject drugs (von Haeften and Kenski, 2001; Kenski and others, 2001).
Once the significant constructs are identified, analyses of the beliefs underlying those
constructs can determine which specific behavioral, normative, or control beliefs are
most strongly associated with intention and behavior, thus providing empirically identified targets for intervention efforts.
Uses for and Evidence to Support TRA/TPB
The name
Theory of Reasoned Action
has often led to the misrepresentation that the
focus is purely on “rational behavior” (for example, St. Lawrence and Fortenberry,
2007). This is far from correct. A fundamental assumption of TRA is that individuals are “rational actors” who process information and that underlying reasons determine motivation to perform a behavior. These reasons, made up of a person’s behavioral,
normative, and control beliefs, determine his attitudes, subjective norms, and perceived control, regardless of whether those beliefs are rational, logical, or correct
by some objective standard. (See Fishbein, 2007, for additional discussion regarding
this aspect of the TRA/TPB.) A strength of TRA/TPB is that they provide a framework to discern those reasons and to decipher individuals’ actions by identifying,
measuring, and combining beliefs relevant to individuals or groups, allowing us to
understand their own reasons that motivate the behavior of interest. TRA and TPB do
not specify particular beliefs about behavioral outcomes, normative referents, or control beliefs that should be measured. As noted in the examples, relevant behavioral
outcomes, referents, and control beliefs will likely be different for different populations and behaviors.
TRA and TPB provide a framework to identify key behavioral, normative, and
control beliefs affecting behaviors. Interventions can then be designed to target and
change these beliefs or the value placed on them, thereby affecting attitude, subjective norm, or perceived control and leading to changes in intentions and behaviors.
TRA/TPB has been applied to explain a variety of health behaviors, including ex-
ercise, smoking and drug use, HIV/STD-prevention behaviors, mammography use,
clinicians’ recommendation of and provision of preventive services, and oral hygiene
behaviors. These studies generally have supported perceived control as a direct predictor of both intentions and behaviors (Albarracin, Johnson, Fishbein, and Muellerleile, 2001; Ajzen, 1991; Blue, 1995; Craig, Goldberg, and Dietz, 1996; Godin and
Kok, 1996; Millstein, 1996; Montaño, Phillips, and Kasprzyk, 2000; Montaño, Thompson, Taylor, and Mahloch, 1997). However, most studies have used direct measures
of perceived control, rather than computing perceived control from measures of control beliefs and perceived power concerning specific facilitators and constraints. The few studies that have measured control beliefs (indirect measure) them to be important predictors of intentions and behaviors (Ajzen and Driver, 1991; Kasprzyk,
Montaño, and Fishbein, 1998). Clearly, if perceived behavioral control is an important determinant of intentions or behaviors, knowledge of the effects of control beliefs concerning each facilitator or constraint would be useful in the development of interventions.