February 27, 1999

Future Directions - 1 October 21, 1999

Future Directions in Research on Humanistic Psychotherapy William B. Stiles Miami University

Stiles, W. B. (2002). Future directions in research on humanistic psychotherapy. In D. J. Cain & J. Seeman (Eds)., Humanistic psychotherapies: Handbook of research and practice (pp. 605-616). Washington, DC: American Psychological Association.

Acknowledgments I thank Robert Elliott, Larry M. Leitner, and this book's editors for comments on drafts of this chapter.

Address for Correspondence: William B. Stiles Department of Psychology Miami University Oxford, OH 45056, USA Telephone: +1-513-529-2405 Fax: +1-513-529-2420 Email: [email protected]

Future Directions - 2

Future Directions in Research on Humanistic Psychotherapy I was pleased to be invited to write this brief chapter on "future directions in research," but I had a few misgivings. "Future directions" can sound like predictions, for which I have no talent, or, worse, prescriptions. I am wary of individuals or panels who presume to set a research agenda for others, and I feel ambivalent--uncomfortable and guilty as well as honored--about assuming that role myself. My discomfort is not so much about such (misconstrued) prescriptions' direct influence on researchers, who will judge for themselves whether a recommendation is worth the enormous effort that any research entails, as about the possible influence on evaluators (e.g., reviewers of grant proposals or submitted manuscripts), who could use conformity to the prescriptions unthinkingly to judge a project's value. Nevertheless, I do have some observations and opinions about research on humanistic psychotherapy, which I am happy to offer here (and elsewhere, in references I have cited below) for consideration by future researchers. After an initial section, meant as an endorsement of methodological pluralism, I comment on several categories of research on humanistic therapies. The Facts Are Friendly The heading quotes Carl Rogers (1961, p. 25), who was referring to scientific research. Nevertheless, humanistic theorists and therapists have often considered research as dehumanizing. Perhaps psychological research's frequent focus on mechanical cause and effect and on linear relations among quantified variables seems to constrict the understanding of human experience (see discussion by Walsh & McElwain, this volume). A sad consequence, I think, is that humanistic therapies have been researched less than they should have been. I believe that this view of research is too narrow--based partly on a mistaken impression that psychological research must imitate research in chemistry or engineering. Science encompasses any comparison of ideas with observations. Numbers are admittedly remarkable; in comparison to words, their meaning is relatively stable across time and people, so they allow scientists to say more or less the same thing to everybody. Likewise, experimental designs and statistical analyses are much to be admired for their precision and


potential generality. However, many of the most interesting phenomena with which humanistic theories and therapies are concerned, such as the unique life experiences of individuals, cannot be well represented as numbers or as variables susceptible to manipulation or control using currently available techniques (Stiles, 1993). Humanistic researchers need not let their own or others' admiration of precise methods trap them into "looking under the lamppost" (after the story of the inebriated man who dropped his keys in a dark alley but looked for them under a streetlight because the light was better), that is, into using methods that seem elegant but are nevertheless inappropriate for the topic of interest. If a topic cannot be adequately addressed using available experimental designs and linear statistical analyses--and many cannot--then other observational techniques are available. Among these are case studies and other qualitative approaches, such as idiographic studies, ethnography, ethnomethodology, grounded theory, protocol analysis, discourse analysis, conversational analysis, constructivist approaches, phenomenology, or hermeneutic investigation (e.g., see Rennie's chapter in this volume). Distinctive characteristics of qualitative research that could make it suitable for addressing humanistic topics may include the following: (a) results that are reported in words rather than only in numbers (b) use of many descriptors rather than restriction to a few common dimensions or scales, (c) use of investigators' empathic understanding of participants' inner experiences as data, (d) understanding and reporting of events in their unique context, (e) selecting participants or texts or other material to study because they are good examples rather than because they are representative of some larger population, (f) reports that use alternatives to traditional didactic discourse , including narratives or hermeneutic interpretations, (g) accommodating unpredictability due to sensitive dependence on initial conditions (small initial events may have huge consequences), (h) empowering of participants considered as a legitimate purpose of the research (e.g., encouraging them to change their social conditions), and, above all, (i) tentativeness in interpretations (Stiles, 1993, in press). Even though the conclusions of qualitative research may be tentative, however, the gain in realism can compensate for losses in generality (cf. Levins, 1968).


Case studies in particular are under-used (Farmer, 1999; Stiles, 1995). Of course, case studies have the usual weaknesses of anecdotal research--selection of data, possible distortions of introspective reports, investigator biases, lack of generality, and so forth. But humanistic therapists are familiar with the need to hold information tentatively in clinical contexts, and they can similarly report case-based investigations without claiming certainty or generality. A multiple case study approach (Rosenwald, 1988) might be particularly well suited to psychotherapy research. Therapists who have treated similar clients might collaborate in assembling multiple cases around a common theme for research reports. Outcome Research Randomized clinical trials (RCTs) of humanistic psychotherapies remain politically necessary, and outcome research using other designs (e.g., pre-post single group comparisons) are also politically valuable. RCTs are a statistical adaptation of the experimental method, which is the closest science has come to a means for demonstrating causality. RCTs may be flawed for many reasons (Haaga & Stiles, in press), and their value for determining mental health policy is controversial (Bohart, O'Hara, & Leitner, 1998; Elliott, 1998; Henry, 1998; Strauss & Kaechele, 1998). The question, "does it work?" is so salient, however, that other questions seem to remain in the background until this one is addressed. According to the latest update of a continuing meta-analysis (Elliott, 1996; Elliott and Greenberg, this volume; Elliott, Greenberg, & Lietaer, 1994), humanistic therapies have shown mean pre-post effect sizes in the range of 1.1 to 1.3, which are very respectable effects. In addition to Elliott and Greenberg's report for Process-Experiential therapy, several other chapters also reported positive effects of specific humanistic treatments; for example, Johnson and Boisvert (this volume) pointed out that outcomes of Relational Enhancement and Emotionally Focused Therapy for couples compare favorably with those of the best-researched alternative treatment, Behavioral Marriage Therapy. However, these reviews were based on relatively small numbers of studies, which were themselves based on small numbers of clients and (as usual) open to challenge on methodological grounds.


Researchers designing RCTs and other outcome studies need to be cognizant of the limitations and likely results. For reasons that have long been puzzling (cf. Rozenzweig, 1936), most alternative psychotherapies appear to be about equivalently effective (Lipsey & Wilson, 1993; Wampold et al., 1997), despite the demonstrated diversity of theories and techniques (Stiles, Shapiro & Elliott, 1986). This paradoxical equivalence is very robust, and it seems unlikely that future comparisons will show humanistic therapies to be hugely more effective or less effective than other therapies. Even when results favoring one treatment are found, they may be at least partly attributable to the investigators' allegiance (including unintended effects of allegiance on how the compared treatments were implemented) more reliably than to the ostensible treatment approach (Luborsky et al., 1999). Perhaps the technical differences among therapies are overshadowed by the common features (e.g., mutual responsiveness in a helping encounter) or by case-to-case variation in how each treatment is realized. An important side benefit of RCT designs and other large-scale outcome studies is providing a context for other sorts of psychotherapy research. Data collected in the course of conducting an outcome study, including tape recordings of sessions, can be used to study alternative outcome measures, individual differences, and the psychotherapeutic process. Though politically less salient, these additional areas of research may be scientifically more informative. Outcome Measurement The political purposes of outcome research demand (a) broadly-accepted outcome measures of (b) criteria that are common across clients that (c) are easy to collect. The lowest common denominator seems to be symptom intensity, assessed via checklists completed by clients, therapists, or external evaluators. Politically more potent, but far more difficult to assess (and much less used), are indices of life changes that have economic implications: job-holding, divorce, hospitalization, or other use of health-related resources. As noted in many of this volume's chapters, humanistic conceptions of therapy's purpose and effects go beyond reducing symptom intensity. Clients undoubtedly notice and care about changes in style of working or relating and other idiosyncratic changes that may be only


tangentially related to the usual criteria used in outcome research. There may be many different outcomes that yield similar levels of symptom relief (Stiles, 1983). Indeed, as Walsh and McElwain (this volume) pointed out, some symptoms, such as existential anxiety, may be productive, and therapists and clients may sometimes consider treatment successful even when it leaves symptom intensity unchanged. Research to assess humanistic therapy's specific effects--as contrasted with its efficacy or its effectiveness--demands continuing creative ingenuity. Rating scales designed to assess dimensions beyond symptom intensity or global evaluations can be useful in this respect. Q-sort measures represent a still-underexploited alternative (cf. Ablon & Jones, 1998). Changes that are unique to individuals can be documented using qualitative approaches. Of course, anecdotal or other ad hoc measures may not be potent politically in justifying the cost of psychotherapy. Multiple measurement approaches--symptom intensity checklists and, say, humanistically-informed qualitative accounts--probably are best used in parallel. In their own thinking and writing, researchers may wish to distinguish between political and conceptual contributions, but they would be foolish, I think, to restrict their measures to only one of these categories. Diagnosis and Differential Treatment Placing people in categories is potentially dehumanizing. Diagnoses can oversimplify and distort perceptions of the person to whom they are applied. For therapists, the danger lies in responding to a textbook concept or a stereotype rather than to the client's immediate and unique life experience. Diagnoses may induce a false sense of security, a feeling that one knows more about another person than one actually does. On the other hand, ignoring diagnosis or psychological assessment can be a form of antiintellectualism, of which humanistic therapists are sometimes accused. We must use categories to think at all. Whether the categories come from diagnostic manuals or textbooks or supervisors or parents or folklore or television, there is a risk of reification--confusing the concept with the reality. Stereotypes and other preconceptions can be dehumanizing and oversimplifying and


distorting regardless of where they come from. Insofar as therapists cannot avoid having some sort of preconceptions, the goal must be to hold those preconceptions tentatively. I suggest that therapists and researchers serve clients best by gathering a rich repertoire of categories--learning about the full range of human experience from whatever sources are available, including research results and diagnoses. In dealing with clients, responsible humanistic therapists apply all knowledge tentatively, always comparing their current understanding with new observations and always ready to withdraw inferences that are contradicted by their client's individual experience. Bracketing--trying to ignore diagnostic information in listening to clients--may help therapists avoid treating people as diseases, but it risks overlooking useful perspectives that diagnoses can add. Diagnostic categories need not be dehumanizing, so long as therapists use them to understand rather than to substitute for understanding their clients' personal experience. Case studies have suggested that the common clinical manifestations reflected in DSM diagnoses may reflect common client experiences (Bohart, 1990; Schneider & Stiles, 1995). People who appear as depressed or as borderline or as schizophrenic may experience the world in distinctive ways that differ from their therapists' experience. Knowledge of a client's diagnosis--and the distinctive experiences it may entail--may thus help a therapist understand what the client is trying to say more quickly or more deeply. The work of Prouty (this volume) takes important steps in this direction by focusing on repertoires of therapeutic techniques useful for working with people with particular diagnoses (e.g., schizophrenia). Such research might be expanded by shifting the focus slightly to describe the experiences of these clients. Explicitly humanistic alternatives to traditional diagnostic systems (e.g., Leitner, 1995; Leitner & Pfenninger, 1994) may offer additional, particularly useful ways for humanistic therapists to understand clients; however even humanistically-inspired categories and dimensions must be applied tentatively. Reification of diagnostic concepts can be problematic on many levels. For example, it can seem a matter of professional ethics and responsibility to provide the best-researched treatment for each client's problem. If problems are required (e.g., by research protocols or third-party


payers) to be defined in terms of diagnoses or similar descriptors (e.g., depression, phobia, panic), then it may seem that research on treatments must target diagnostic categories to address treatment selection in an ethical and responsible way. Research in which the treatments are understood as addressing the unique needs of individuals can be seen as irrelevant. And delivering treatments that lack diagnosis-specific efficacy data may be viewed by some people as unethical. Process Research Process research recognizes that there is no long-term change without short-term change. It investigates how changes take place within and between sessions. The most powerful results reviewed in this book, I think, were those dealing with replicated categories of events within sessions--broadly in line with the concept of the "events paradigm" described by Rice and Greenberg (1984). Some examples include: (a) research on markers of readiness to engage in experiential tasks by Greenberg and collaborators, reported in several chapters (e.g., Elliott & Greenberg; Strümpfel; Johnson & Boisvert) and Watson's related extension to markers of readiness for types of empathic responses; (b) processing proposals research by Sachse; (c) Rennie's work on deference and story-telling; (d) identification of ruptures in the therapeutic alliance (Assay & Lambert; similarly, the "disturbances in reflexivity" reported by Rennie); and (e) Prouty's categories of contact. Stages of group development (Page et al.) also are often signaled by "barometric events," which could similarly be considered as markers of participants' internal states or readiness to engage in particular tasks (Stiles, 1979). The results of these investigations link recognizable markers with readiness for specific types of interventions in clinically useful ways. Moreover, because they describe psychotherapy at a level close to that used in psychotherapeutic theories, these process studies address the theories better than outcome research can. For example, the descriptions of the softening of one voice towards another in a two-chair exercise is not only a clinically important sign, but a theoretical elaboration of the process by which internal conflicts are resolved. Therapy theories are meant to explain how therapy works. The bald hypothesis that a


treatment is effective, which is what outcome research tests, is a relatively undifferentiated consequence of the theory. Even the repeated finding that positive therapeutic relationships (alliances) are associated with positive outcomes glosses over the important intermediate steps. By contrast, events paradigm research traces sequences within sessions. Typically the sequence begins with an observable marker, which signals some internal state of the client, which implies some readiness for a therapeutic intervention, whose effect can be gauged by the client's subsequent behavior. In discussing process research, I should also mention a limitation: What may seem the most obvious strategy for assessing the effect of process components--measuring them and correlating them with measures of outcome--is blocked by the phenomenon of responsiveness, the fact that participants' behavior is affected by emerging context (Stiles, Honos-Webb, & Surko, 1998). Therapists normally try to respond to a client's emerging requirements with interventions that are appropriate, given their theoretical approach, the client's personality and background, and the therapeutic context. To the extent that they succeed, clients tend to experience optimum levels of those interventions. Clients who need less tend to receive less, and--insofar as they still got as much as they needed--their outcomes tend to be just a good as those of clients who needed more and got more. As a result, levels of the process components do not predict outcome. Crucially important process components may have null or even negative correlations with outcomes (Stiles, 1988). Conversely, the relative strengths of process variables' correlations with outcome are uninformative. Variables with null correlations may be as important or more important than variables with significant positive correlations. Thus, processoutcome correlations are not to be trusted. For an illustration and debate of this point, see the series of articles by (a) Stiles and Shapiro (1994), (b) Silberschatz (1994), (c) Sechrest (1994), (d) Stiles (1994), (e) Hayes, Castonguay, and Goldfried (1996), and (f) Stiles (1996). Of course, reliable positive correlations generally have interesting explanations. However, these may not be the obvious ones because of responsiveness or because of possible confounding variables.


The responsiveness problem has frequently been overlooked, and a great deal of process research (including mine!) has futilely sought linear process-outcome relations. Alternative research strategies may require reconceptualizing the problem (Stiles, Honos-Webb, & Surko, 1998). Unfortunately, researchers' and reviewers' focus on correlations with outcomes has often obscured important achievements in process measurement, in precise descriptions of what happens (e.g., of therapists' and clients' verbal and nonverbal behavior), and in comparisons of the process the across roles (e.g., therapist and client), treatments (e.g., client-centered, gestalt, psychoanalytic, cognitive-behavioral), and settings (Stiles, Honos-Webb & Knobloch, 1999). Humanistic Concepts, Heroes, and Values Psychotherapy is a laboratory as well as a source of ideas for research (Stiles, 1992) and a treatment (Greenberg, 1991; Stiles, 1999). I think psychotherapy offers exceptional opportunities to study fundamental conceptions of humanistic theories. Examples of such topics include the role of interpersonal power (e.g., the therapist's over the client), the psychology of focusing and felt shifts, the softening of negative emotion in two-chair exercises, the assumption that emotion represents information about an experience's value, the effects of directed repetition and exaggeration of nonverbal behaviors, and the nature of the self. Research based in psychotherapy could address issues that divide humanistic therapies. For example, Rogers's (1951, 1959) assumption of an organismic valuing process--that a person's value judgments are fundamentally trustworthy--was an underpinning of his radically nondirective approach. The scope and limits of this assumption are clearly controversial within humanistic therapies, illustrated by the varied discussions of directive interventions in this book. Methodological ingenuity is needed to find ways to investigate the alternative conceptions. Humanistic therapies have heroes--for example, Carl Rogers and Fritz Perls--whose visions have defined the field. Their deep understanding allowed them to be effective and we who follow try to reproduce their understanding, so we can be equally effective. The heroes' vision is not conveyed by a single reading of their words. On each re-reading, their words (and their tape-recorded actions) take on new meanings. We seem to understand more of what they


meant each time we return. To put it another way, the major humanistic theories are partly implicit and continually emerging. The deep appeal of the heroes' visions can make them competitors with research as means of quality control on ideas. That is, to assess the quality of our ideas, we may turn to the words of the heroes rather than to observations. Perhaps this is not entirely misguided. Research based on a weak understanding of the vision--for example, reductionistic operationalizations of humanistic concepts--is dismissed by proponents, and hence has little impact on quality control. Comparing a new idea with the writings of the master may, paradoxically, offer a better test of its fit with clinical reality. On the other hand, there are obvious long-term dangers in such a closed system, in which ideas are judged only in relation to other ideas. Part of the research task is to articulate the vision in ways that are simultaneously acceptable to proponents and susceptible to observation. In good research, when the ideas are compared with the observations, the ideas are thereby changed -- strengthened, weakened, qualified, or elaborated. Thus, good research on humanistic concepts must put those concepts at risk. The risk may be compounded for humanistic researchers, whose concepts may overlap extensively with their values. Research will not tell us what is good, though people can use research results to argue for their own views and values. Research is most productive, I think, when researchers have the courage to face potentially unfriendly findings with an underlying confidence that the facts are friendly.


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