Although premature discontinuation is occurring at a lower rate than what was estimated 20 years ago (Wierzbicki & Pekarik, 1993), it is still a significant problem, with about 1 in every 5 clients dropping out of therapy. Special efforts should be made to decrease premature discontinuation, particularly with clients who are younger, have a personality or eating disorder diagnosis, and are seen by trainee clinicians.

Findings are interpreted with reference to other reviews. Possible clinical applications include careful choice and supplementing of treatment setting/delivery according to the diagnosis, and use of preparatory strategies. Suggestions for future research include standardization of operational definitions of dropout, specification of timing of dropout, and exploration of additional moderator variables.

An important part of evidence-based practice is to include client preferences in the treatment decision-making process. However, based on previous reviews of the literature there is some question as to whether including client preferences actually has an effect on treatment outcome. This meta-analytic review summarized data from over 2,300 clients across 26 studies comparing the treatment outcome differences between clients matched to a preferred treatment and clients not matched to a preferred treatment. The findings indicate a small significant effect (r=.15, CI(.95): .09 to .21) in favor of clients who received a preferred treatment. The binomial effect size indicated that matched clients have a 58% chance of showing greater improvement, and further analysis indicate that they are about half as likely to drop-out of treatment when compared with clients not receiving a preferred treatment. Study design was seen to be a moderating variable in that partially randomized preference trials may underestimate the treatment preference effect. Implications for best practice standards are discussed.

Client preferences are recognized as a key component to evidence-based practice; however, research has yet to confirm the actual influence preferences have on treatment outcome. In this meta-analysis, we summarize results from 35 studies that have examined the preference effect with adult clients. Overall, clients who were matched to their preferred therapy conditions were less likely to drop out of therapy prematurely (OR=.59, p<.001) and showed greater improvements in treatment outcomes (d=.31, p<.001). Type of preference (role, therapist, or treatment type) was not found to moderate the preference effect, but study design was found to be a significant moderator, with randomized controlled trials showing the largest differences between preference-matched clients and nonmatched clients. These results underscore the centrality of incorporating patient preferences when making treatment decisions. Clinical examples and therapeutic practices are provided.

Client preferences in psychotherapy reflect specific conditions and activities that clients desire in their treatment, with increasing evidence pointing to preference accommodation as facilitating psychotherapy outcomes. This updated meta-analysis establishes the magnitude of the effect of client preference accommodation in psychotherapy. Based on data from 53 studies and over 16,000 clients, preference accommodation was associated with fewer treatment dropouts (OR = 1.79) and more positive treatment outcomes (d = 0.28) than providing client with a nonpreferred treatment or psychotherapy condition. The preference effect was moderated by study design, timing and type of outcome measurement, and client diagnosis. It was not moderated by year of publication, treatment duration, preference type, treatment options, client age, client gender, client ethnicity, or client years of education. The authors provide a case example of preference accommodation and practice recommendations for working with client preferences.