Nurses' intentions to administer morphine for post-operpative pain : an application of Azjen's theory of planned behaviour
Jurgens, Douglas W.
The present study was designed to investigate cognitive predictors of nurses' decisions to administer morphine for pain post-operatively using the Theory of Planned Behaviour (Ajzen, 1985; 1991). Hypotheses derived from the theory were that theoretical determinants of behavioural intention (attitude toward the behaviour, the subjective norm and perceived behavioural control) should combine to predict intention. Beliefs about the likelihood that certain events would occur that might prevent performance of the behaviour and the rated importance of these events were hypothesized to combine multiplicatively in the prediction of perceived behavioural control and were hypothesized to correlate more weakly with intentions than attitudes. Finally, scores on the Pain Beliefs Questionnaire (Jurgens, 1995) were hypothesized to have only indirect effects on behavioural intention mediated by constructs considered more proximal to behavioural intention in the Theory of Planned Behaviour. A preliminary study determined relevant control beliefs which were examined for their utility in predicting perceived behavioural control in the main study. The preliminary study also piloted the vignette for plausibility, clarity, comprehensiveness and accuracy. One hundred forty-nine registered nurses employed at fourteen general hospitals in Saskatchewan and involved in the care of patients who experience pain constituted the sample in the main study. Subjects responded to questions with regard to a vignette which described a post-operative patient in pain. Nurse subjects completed scales assessing the independent and dependent variables with regard to performing two behaviours; (a) administering the highest narcotic dosage allowed for by the prescription order, and (b) administering the next dose of narcotic analgesia in the shortest interval allowed for by the prescription order. Ratings with regard to each of the two behaviours were combined to derive variable scores for the behavioural category of nurses' administration of morphine for pain post-operatively. Results provided strong support for the application of the Theory of Planned Behaviour to the behaviours involved in the administration of morphine for pain post-operatively. Attitude toward the behaviour, and perceived behavioural control emerged as the significant predictors of behavioural intention, with attitude toward the behaviour accounting for the most variance. No evidence for any of the interactions proposed by Ajzen (1985) was found. Evidence for mediation of distal model components by more proximal components was found. Implications for Ajzen's theory as well as applied implications and limitations of the current research are discussed.