USING 2 FACTOR STRUCTURES OF THE MENTAL ADJUSTMENT TO CANCER (MAC) SCALE FOR ASSESSING ADAPTATION TO BREAST-CANCER

The validity and reliability of two factor structures of the Mental Ad justment to Cancer (MAC) scale for assessing coping style was assessed by examining the relationship between the subscales, psychological di stress, and quality of life (QOL) among Stage II and Stage TV breast c ancer patients in four phases. First, MANOVAs assessed differences in coping, distress, and QOL across disease stages. Second, for each MAC factor structure, canonical correlation analyses assessed the relation ship between coping styles, distress, and QOL, for each disease-stage group separately. Third, structural equation modeling (SEM) assessed t he relationship among coping styles, distress, and QOL for all partici pants. Finally, the internal consistency of both MAC factor structures was assessed using Chronbach's alpha. The results were as follows: (1 ) significant differences across disease stages were found for coping styles using either the Watson or the Schwartz MAC subscales, but ther e were no differences in levels of distress or QOL; (2) for both MAC f actor structures, coping style was found to be highly related to emoti onal distress and QOL, however, the strengths of the correlations betw een individual coping styles and distress/QOL indicators varied across disease stages; (3) SEM indicated that coping style was significantly related to distress and QOL when stage of disease was not considered, and that coping style and indicators of distress/QOL are separate, bu t highly correlated factors, as opposed to a single latent construct; and, (4) the Watson MAC subscales showed slightly better internal cons istency than the Schwartz MAC subscales. Taken together, these finding s highlight: (i) the validity of both MAC factor structures for clinic al and research use with American breast cancer patients; (ii) the rol e of coping style as a mediator between disease stage and psychologica l distress and QOL; and, (iii) the need for refinement of certain Wats on and Schwartz subscales. (C) 1998 John Wiley & Sons, Ltd.