Previous research has indicated that postoperative pain, mood and analgesic requirements are influenced by diverse demographic and psychological variables. The data, however, are inconsistent and the extent of these influences has not been explored using multivariate statistical methods. In the present investigation patients scheduled for elective gallbladder surgery were examined for levels of pain, mood and analgesic needs, and the data were analyzed by using stratified stepwise multiple regression analysis. The results indicate that approximately half of the variability in the postoperative outcome measures could be predicted by a set of variables which include the patient's anxiety, extroversion, depression, educational level, previous chronic pain syndromes, and bias toward using medication. The implications of these results are discussed in relation to pain management strategies for surgical populations.