[Predictability of pain after laparoscopic cholecystectomy with self-efficacy and locus of control].

UNLABELLED: The study consists of a prospective randomized controlled clinical trial of patients undergoing laparoscopic cholecystectomy. Besides medical and sociodemographic data, two personality factors--self-efficacy and locus of control--were found to predict postoperative pain. Self-efficacy describes the expectations of a person to successfully execute the behavior required to produce behavioral outcomes. Locus of control, in the extreme case, is a personality factor which is represented by an internal orientation in which the individual believes that rewards are brought about by his own action, versus an external orientation, in which the individual believes that rewards are the result of powerful others or chance factors and fate. We postulate that the two personality factors correlate with postoperative parameters of pain and that there are also multiple correlations between them.

METHODS: For the two personality factors we applied two questionnaires which were given to the patients preoperatively. One is well established and the second one was developed and tested especially for this study by us. We used subjective pain, demand for and quantity of analgetics as parameters of postoperative pain until the 3rd day after surgery.

RESULTS: The statistical analysis of 56 patients revealed that the two personality factors proved to be the most relevant and significant factors (p<0.05-0.001) to predict and also to explain high rate of variance up to 60% of postoperative pain. Patients with a high expectation of self-efficacy in pain management and an internal locus of control had a significantly lower subjective pain, demand for and quantity of analgetics than patients with low expectations of self-efficacy or a high external orientation with chance factor and fate in control. Medical and sociodemographic variables did not predict any parameters of pain. Some surgical factors were kept constant.

DISCUSSION: These findings underline the importance of personality factors also in postoperative pain, which can be predicted by self-efficacy and locus of control. This result means for us that self-efficacy and locus of control influence the cognates of personal pain perception within the context of the individual history of experiences and seem to be changeable preoperatively by special psychological training.