Depression and anxiety are highly prevalent [1] and are often treated in the primary care setting [2]. The effectiveness of psychosocial treatments such as problem-solving treatment has been established [3–6], but results in the primary care setting are sometimes less than one would expect based on the outcomes of efficacy studies under more stringently controlled circumstances [7–9].

A potentially relevant factor with a negative influence on treatment outcome is the presence of multiple physical symptoms [10, 11]. Up to 70% of depressed patients present themselves to their general practitioner with such physical symptoms instead of psychological symptoms [12]. Given this frequent co-occurrence, it seems plausible that multiple physical symptoms interfere with the course and outcome of symptoms of depression and anxiety. This hypothesis is in line with findings regarding the influence of concomitant physical symptoms on the course of major depressive disorder [11].