Abstract
IPT was originally derived from what were considered to be appropriate clinical techniques, in order to mimic ‘good supportive therapy’ in clinical trials. IPT was not developed from a theoretical model and consequently it does not have a specific theoretical foundation for practitioners to draw on. Existing IPT research has focused on outcomes, but little is known about how or why IPT works. Literature pertaining to the epistemology of professional knowledge suggests that professionals make use of espoused and implicit theories to guide their work. Those wishing to train in IPT are required to have completed training in a relevant field and therefore may approach IPT with an existing repertoire of theories. This study aimed to explore how IPT practitioners account for theory and evidence in their practice. Interviews were conducted with eight IPT practitioners, and analysed using interpretative phenomenological analysis (IPA). The practitioners made use of a repertoire of implicit and espoused theories, applied during practice and retrospectively. The way practitioners drew on theory and evidence was influenced by their professional context, perceived level of experience, and their individual experiences and values. This study highlights differences in the way practitioners currently make sense of IPT, and the potential implications of appending theory in a post-hoc fashion. Future research might focus specifically on examining the range of espoused and implicit theories IPT practitioners employ, and their implications for practice.