What is the appropriate time to measure outcome and process factors in psychodynamic psychotherapy?

Different instruments and methods for measuring factors related to the progress and effectiveness of psychodynamic psychotherapy (PDT) have been widely discussed in the literature. However, there are no established guidelines on the most appropriate time to perform these measurements. The aim of this study is to problematize what is the appropriate time to measure the initial outcomes (symptoms, interpersonal relationships, quality, and social role) and process factors (alliance) in the early stages of PDT. A naturalistic cohort study was conducted, following 304 patients during the first six months of psychotherapy. The therapeutic alliance was evaluated after four sessions; symptoms, interpersonal relationships, and social role were evaluated at intake and after 12 and 24 sessions. Our results indicate that four sessions were sufficient to measure the bond dimension of the therapeutic alliance, while more time is probably needed to adequately measure other aspects of the therapeutic alliance, such as tasks and goals. However, 12 sessions of treatment proved sufficient to detect improvements in all dimensions of the outcome instruments with moderate effect sizes, and those gains were stable at the 24th session. According to our findings, 12 sessions seem to be sufficient to assess initial gains in PDT, although more studies are needed to evaluate the appropriate time to assess all aspects of the therapeutic alliance. Further studies are also required to evaluate the appropriate time to assess intermediate and long-term progress with regard to symptoms, interpersonal relations, social role and personality reorganization.