PURPOSE: The purpose of this study was to explore how the relationship between 
care recipients' problem behaviors and caregivers' depressive symptoms varies as 
a function of caregiver mastery, controlling for the effects of caregiver age, 
gender, and relationship to the care recipient in caregivers of people with 
primary malignant brain tumor (PMBT).
DESIGN: A cross-sectional design was used to gather data via telephone 
interviews from 95 caregivers of people with primary malignant brain tumor, 
recruited from 2003 to 2004 from a brain tumor treatment center, two national 
support groups, and a statewide cancer registry.
METHODS: Measures for the study included the Neuropsychiatric 
Inventory-Questionnaire, Caregiver Mastery, and the Center for Epidemiologic 
Studies-Depression. A stepwise regression procedure was used to evaluate 
potential moderating and mediating relationships.
FINDINGS: Data did not indicate that caregiver mastery was a moderating 
variable. The analysis showed caregiver mastery as a partial mediator, with both 
a direct effect of care recipients' problem behaviors on caregivers' depressive 
symptoms and an indirect effect through caregiver mastery. Concerning the 
indirect effect, care recipients' problem behaviors were related to lower levels 
of caregiver mastery, which in turn were related to more depressive symptoms in 
caregivers.
CONCLUSIONS: Findings showed a link between care recipients' problem behaviors 
and caregivers' depressive symptoms, a relationship that has not been well 
established in oncology. This association indicates one mechanism through which 
problem behaviors in the care recipient might lead to caregiver depressive 
symptoms.