The continuing potential relevance of equivalence and allegiance to research on psychological treatment of psychosis

In response to Tarrier and colleagues' critique of our recent paper (Paley & Shapiro, 2002), we note that the equivalent outcomes paradox and investigator allegiance problem remain of considerable potential relevance to research on psychological treatment of psychosis. We note in particular their salience to recent work reported by Tarrier and his colleagues. We also comment that our preparedness to entertain the contributions of diverse treatment models does not entail a theoretical approach.