Date of Award

Fall 2011

Degree Type


Degree Name

Doctor of Philosophy (PhD)




Kathleen Martin Ginis




The purpose of this dissertation was to examine the use of health risk communications as a strategy to change risk perceptions and motivate leisure time physical activity (LTPA) among people with spinal cord injury (SCI). Guided by protection motivation theory (PMT; Rogers, 1983) and the extended parallel processing model (EPPM; Witte, 1992), two strategies were examined as unique approaches to enhancing the effectiveness of health risk information. First, risk information was tailored to individualized, objective data regarding participants’ health risk. Second, risk information was supplemented with framed leisure time physical activity (LTPA) efficacy messages. Gain-framed messages emphasized the benefits of LTPA, whereas loss-framed messages emphasized the risks of inactivity. The relative effectiveness of gain- versus loss-framed messages was considered within the context of the EPPM (Witte, 1992). A secondary purpose of the dissertation was to explore cognitive processing in relation to framed LTPA messages. The attention and elaboration phases of cognitive processing were examined for gain- and loss-framed LTPA messages following exposure to health risk information. Three experiments were conducted to 1) test the effectiveness of individualized health risk information for changing health risk perceptions and LTPA among people with SCI, 2) test the relative effectiveness of gain- and loss-framed LTPA efficacy messages presented following health risk information for changing LTPA response efficacy and LTPA intentions among people with SCI, and, 3) investigate the relative attention given to gain-framed versus loss-framed LTPA response efficacy messages following presentation of health risk information to university students. The theoretical and pragmatic contributions are discussed.

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