di 2

In Search of How People Change Applications to Addictive Behaviors

James O. Prochaska Cancer Prevention Research Consortium, University of Rhode Island

Carlo C. DiClemente University of Houston John C. Norcross University ofScranton

How people intentionally change addictive behaviors with and without treatment is not well understood by behavioral scientists. This article summarizes research on self-ini- tiated and professionally facilitated change of addictive behaviors using the key transtheoretical constructs of stages and processes of change. Modification of addictive behaviors involves progression through five stages—pre- contemplation, contemplation, preparation, action, and maintenance—and individuals typically recycle through these stages several times before termination of the ad- diction. Multiple studies provide strong support for these stages as well as for a finite and common set of change processes used to progress through the stages. Research to date supports a transtheoretical model of change that systematically integrates the stages with processes of change from diverse theories of psychotherapy.

Hundreds of psychotherapy outcome studies have dem- onstrated that people successfully change with the help of professional treatment (Lambert, Shapiro, & Bergin, 1986; Smith, Glass, & Miller, 1980). These outcome stud- ies have taught us relatively little, however, about how people change with psychotherapy (Rice & Greenberg, 1984). Numerous studies also have demonstrated that many people can modify problem behaviors without the benefit of formal psychotherapy (Marlatt, Baer, Donovan, & Divlahan, 1988; Schachter, 1982; Shapiro et al., 1984; Veroff, Douvan, & Kulka, 1981a, 1981b). These studies have taught us relatively little, however, about how people change on their own.

Similar results are found in the literature on addic- tive behaviors. Certain treatment methods consistently demonstrate successful outcomes for alcoholism and other addictive behaviors (Miller & Hester, 1980, 1986). Self- change has been documented to occur with alcohol abuse, smoking, obesity, and opiate use (Cohen et al., 1989; Or- ford, 1985; Roizen, Cahaland, & Shanks, 1978; Schachter, 1982; Tuchfeld, 1981). Self-change of addictive behaviors is often misnamed "spontaneous remission," but such change involves external influence and individual com- mitment (Orford, 1985; Tuchfeld, 1981). These studies demonstrate that intentional modification of addictive behaviors occurs both with and without expert assistance. Moreover, these changes involve a process that is not well understood.

Over the past 12 years, our research program has been dedicated to solving the puzzle of how people in- tentionally change their behavior with and without psy- chotherapy. We have been searching for the structure of change that underlies both self-mediated and treatment- facilitated modification of addictive and other problem behaviors. We have concentrated on the phenomenon of intentional change as opposed to societal, developmental, or imposed change. Our basic question can be framed as follows: Because successful change of complex addictions can be demonstrated in both psychotherapy and self- change, are there basic, common principles that can reveal the structure of change occurring with and without psy- chotherapy?

This article provides a comprehensive summary of the research on the basic constructs of a model that helps us understand self-initiated and professionally assisted changes of addictive behaviors. The key transtheoretical concepts of the stages and processes of change are ex- amined, and their applications to a variety of addictive behaviors and populations are reviewed. This transtheo- retical model offers an integrative perspective on the structure of intentional change.

Stages of Change One objective of treatment outcome research in the ad- dictions is to establish the efficacy of interventions. How- ever, study after study demonstrates that not all clients suffering from an addictive disorder improve: Some drop out of treatment, and others relapse following brief im- provement (Kanfer, 1986; Marlatt & Gordon, 1985). In- adequate motivation, resistance to therapy, defensiveness, and inability to relate are client variables frequently in- voked to account for the imperfect outcomes of the change enterprise. Inadequate techniques, theory, and relationship skills on the part of the therapist are intervention variables frequently blamed for lack of therapeutic success.

In our earliest research we found it necessary to ask

Bernadette Gray-Little served as action editor for this article. This research was supported in part by Grants CA27821 and

CA50087 from the National Cancer Institute. Correspondence concerning this article should be addressed to

James Q Prochaska, Cancer Prevention Research Consortium, University of Rhode Island, Kingston, RI 02881.

September 1992 • American Psychologist 1102

Copyright 1992 by the American Psychological Association, Inc. 0OO3-066X/92/$2 00

when changes occur, in order to explain the relative con- tributions of client and intervention variables and to un- derstand the underlying structure of behavior change (DiClemente & Prochaska, 1982; Prochaska & Di- Clemente, 1983). Individuals modifying addictive behav- iors move through a series of stages from precontempla- tion to maintenance. A linear schema of the stages was discovered in research with smokers attempting to quit on their own and with smokers in professional treatment programs (DiClemente & Prochaska, 1982). People were perceived as progressing linearly from precontemplation to contemplation, then from preparation to action, and finally into maintenance. Precursors of this stage model can be found in the writings of Horn and Waingrow (1966), Cashdan (1973), and Egan (1975). Variations of and al- ternatives to our stage model can be found in more recent writings of Beitman (1986); Brownell, Marlatt, Lichten- stein, and Wilson (1986); Dryden (1986); and Marlatt and Gordon (1985).

Several lines of research support the stages of change construct (Prochaska & DiClemente, 1992). Stages of change have been assessed in outpatient therapy clients as well as self-changers (DiClemente & Hughes, 1990; DiClemente & Prochaska, 1985; DiClemente, Prochaska, & Gilbertini, 1985; Lam, McMahon, Priddy, & Gehred- Schultz, 1988; McConnaughy, DiClemente, Prochaska, & Velicer, 1989). Clusters of individuals have been found in each of the stages of change, whether the individuals were presenting for psychotherapy or attempting to change on their own. Stages of change have been ascer- tained by two different self-report methods: a discrete categorical measure, which assesses the stagefrom a series of mutually exclusive questions (DiClemente et al., 1991), and a continuous measure, which yields separate scales for precontemplation, contemplation, action, and maintenance (McConnaughy et al., 1989; McConnaughy, Prochaska, & Velicer, 1983).

In our original research we had identifiedfive stages (Prochaska & DiClemente, 1982). But in principal com- ponent analyses of the continuous measure of stages, we consistently found only four scales (McConnaughy et al., 1983, 1989). We misinterpreted these data to mean that there were only four stages. For seven years we worked with a four-stage model, omitting the stage between con- templation and action (Prochaska & DiClemente, 1983, 1985, 1986). We now realize that in the same studies on the continuous measures, cluster analyses had identified groups of individuals who were in the preparation stage (McConnaughy et al., 1983, 1989). They scored high on both the contemplation and action scales. Unfortunately we paid more attention to principle component analyses rather than the cluster analyses and ignored the prepa- ration stage. Recent research has supported the impor- tance of assessing preparation as a fifth stage of change (DiClemente etal., 1991; Prochaska &Diclemente, 1992). Following are brief descriptions of each of thefive stages.

Precontemplation is the stage at which there is no intention to change behavior in the foreseeable future. Many individuals in this stage are unaware or underaware

September 1992 • American Psychologist

of their problems. As G. K. Chesterton once said, "It isn't that they can't see the solution. It is that they can't see the problem." Families, friends, neighbors, or em- ployees, however, are often well aware that the precon- templators have problems. When precontemplators pre- sent for psychotherapy, they often do so because of pres- sure from others. Usually they feel coerced into changing the addictive behavior by a spouse who threatens to leave, an employer who threatens to dismiss them, parents who threaten to disown them, or courts who threaten to punish them. They may even demonstrate change as long as the pressure is on. Once the pressure is off, however, they often quickly return to their old ways.

In our studies using the discrete categorization mea- surement of stages of change, we ask whether the indi- vidual is seriously intending to change the problem be- havior in the near future, typically within the next six months. If not, he or she is classified as a precontemplator. Even precontemplators can wish to change, but this seems to be quite different from intending or seriously consid- ering change in the next six months. Items that are used to identify precontemplation on the continuous stage of change measure include "As far as I'm concerned, I don't have any problems that need changing" and "I guess I have faults, but there's nothing that I really need to change." Resistance to recognizing or modifying a prob- lem is the hallmark of precontemplation.

Contemplation is the stage in which people are aware that a problem exists and are seriously thinking about overcoming it but have not yet made a commitment to take action. People can remain stuck in the contemplation stage for long periods. In one study of self-changers, we followed a group of 200 smokers in the contemplation stage for two years. The modal response of this group was to remain in the contemplation stage for the entire two years of the project without ever moving to significant action (DiClemente & Prochaska, 1985; Prochaska & DiClemente, 1984).

The essence of the contemplation stage is commu- nicated in an incident related by Benjamin (1987). He was walking home one evening when a stranger ap- proached him and inquired about the whereabouts of a certain street. Benjamin pointed it out to the stranger and provided specific instructions. After readily under- standing and accepting the instructions, the stranger began to walk in the opposite direction. Benjamin said, "You are headed in the wrong direction." The stranger replied, "Yes, I know. I am not quite ready yet." This is contem- plation: knowing where you want to go but not quite ready yet.

Another important aspect of the contemplation stage is the weighing of the pros and cons of the problem and the solution to the problem. Contemplators appear to struggle with their positive evaluations of the addictive behavior and the amount of effort, energy, and loss it will cost to overcome the problem (DiClemente, 1991; Pro- chaska & DiClemente, 1992; Velicer, DiClemente, Pro- chaska, & Brandenburg, 1985). On discrete measures, individuals who state that they are seriously considering

1103

changing the addictive behavior in the next six months are classified as contemplators. On the continuous mea- sure these individuals would be endorsing such items as "I have a problem and I really think I should work on it" and "I've been thinking that I might want to change something about myself." Serious consideration of prob- lem resolution is the central element of contemplation.

Preparation is a stage that combines intention and behavioral criteria. Individuals in this stage are intending to take action in the next month and have unsuccessfully taken action in the past year. As a group, individuals who are prepared for action report some small behavioral changes, such as smoking five cigarettes less or delaying their first cigarette of the day for 30 minutes longer than precontemplators or contemplators (DiClemente et al., 1991). Although they have made some reductions in their problem behaviors, individuals in the preparation stage have not yet reached a criterion for effective action, such as abstinence from smoking, alcohol abuse, or heroin use. They are intending, however, to take such action in the very near future. On the continuous measure they score high on both the contemplation and action scales. Some investigators prefer to conceptualize the preparation stage as the early stirrings of the action stage. We originally called it decision making.

Action is the stage in which individuals modify their behavior, experiences, or environment in order to over- come their problems. Action involves the most overt be- havioral changes and requires considerable commitment of time and energy. Modifications of the addictive behav- ior made in the action stage tend to be most visible and receive the greatest external recognition. People, including professionals, often erroneously equate action with change. As a consequence, they overlook the requisite work that prepares changers for action and the important efforts necessary to maintain the changes following action.

Individuals are classified in the action stage if they have successfully altered the addictive behavior for a pe- riod of from one day to six months. Successfully altering the addictive behavior means reaching a particular cri- terion, such as abstinence. With smoking, for example, cutting down by 50% and changing to lower tar and nic- otine cigarettes are behavior changes that can better pre- pare people for action but do not satisfy the field's criteria for successful action. On the continuous measure, indi- viduals in the action stage endorse statements such as "I am really working hard to change" and "Anyone can talk about changing; I am actually doing something about it." They score high on the action scale and lower on the other scales. Modification of the target behavior to an acceptable criterion and significant overt efforts to change are the hallmarks of action.

Maintenance is the stage in which people work to prevent relapse and consolidate the gains attained during action. Traditionally, maintenance was viewed as a static stage. However, maintenance is a continuation, not an absence, of change. For addictive behaviors this stage ex- tends from six months to an indeterminate period past the initial action. For some behaviors maintenance can

be considered to last a lifetime. Being able to remain free of the addictive behavior and being able to consistently engage in a new incompatible behavior for more than six months are the criteria for considering someone to be in the maintenance stage. On the continuous measure, rep- resentative maintenance items are "I may need a boost right now to help me maintain the changes I've already made" and "I'm here to prevent myself from having a relapse of my problem." Stabilizing behavior change and avoiding relapse are the hallmarks of maintenance.

Spiral Pattern of Change

As is now well-known, most people taking action to mod- ify addictions do not successfully maintain their gains on their first attempt. With smoking, for example, successful self-changers make an average of from three to four action attempts before they become long-term maintainers (Schachter, 1982). Many New Year's resolvers report five or more years of consecutive pledges before maintaining the behavioral goal for at least six months (Norcross & Vangarelli, 1989). Relapse and recycling through the stages occur quite frequently as individuals attempt to modify or cease addictive behaviors. Variations of the stage model are being used increasingly by behavior change specialists to investigate the dynamics of relapse (e.g., Brownell et al., 1986; Donovan & Marlatt, 1988).

Because relapse is the rule rather than the exception with addictions, we found that we needed to modify our original stage model. Initially we conceptualized change as a linear progression through the stages; people were supposed to progress simply and discretely through each step. Linear progression is a possible but relatively rare phenomenon with addictive behaviors.

Figure 1 presents a spiral pattern that illustrates how most people actually move through the stages of change. In this spiral pattern, people can progress from contem- plation to preparation to action to maintenance, but most individuals will relapse. During relapse, individuals re- gress to an earlier stage. Some relapsers feel like failures— embarrassed, ashamed, and guilty. These individuals be- come demoralized and resist thinking about behavior

Figure 1 A Spiral Model of the Stages of Change

TERMINATION

PRECONTEMPLATION (CONTEMPLATION PREPARATIO|

PRECONTEMPLATION CONTEMPLATION PREPAHATIOI

1104 September 1992 • American Psychologist

change. As a result, they return to the precontemplation stage and can remain there for various periods of time. Approximately 15% of smokers who relapsed in our self- change research regressed back to the precontemplation stage (Prochaska & DiClemente, 1986).

Fortunately, this research indicates that the vast ma- jority of relapsers—85% of smokers, for example—recycle back to the contemplation or preparation stages (Pro- chaska & DiClemente, 1984). They begin to consider plans for their next action attempt while trying to learn from their recent efforts. To take another example, fully 60% of unsuccessful New Year's resolvers make the same pledge the next year (Norcross, Ratzin, & Payne, 1989; Norcross & Vangarelli, 1989). The spiral model suggests that most relapsers do not revolve endlessly in circles and that they do not regress all the way back to where they began. Instead, each time relapsers recycle through the stages, they potentially learn from their mistakes and can try something different the next time around (DiClemente etal., 1991).

On any one trial, successful behavior change is lim- ited in the absolute numbers of individuals who are able to achieve maintenance (Cohen et al., 1989; Schachter, 1982). Nevertheless, in a cohort of individuals, the number of successes continues to increase gradually over time. However, a large number of individuals remain in con- templation and precontemplation stages. Ordinarily, the more action taken, the better the prognosis. Much more research is needed to better distinguish those who benefit

Figure 2 Percentage Abstinent Over 18 Months for Smokers in Precontemplation (PC), Contemplation (C), and Preparation (P/A) Stages Before Treatment (N = 570)

Pretest 1 6 12

ASSESSMENT PERIODS

September 1992 • American Psychologist

from recycling from those who end up spinning their wheels.

Additional investigations will also be required to ex- plain the idiosyncratic patterns of movement through the stages of change. Although some transitions, such as from contemplation to preparation, are much more likely than others, some people may move from one stage to any other stage at any time. Each stage represents a period of time as well as a set of tasks needed for movement to the next stage. Although the time an individual spends in each stage may vary, the tasks to be accomplished are assumed to be invariant.

Treatment Implications

Professionals frequently design excellent action-oriented treatment and self-help programs but then are disap- pointed when only a small percentage of addicted people register, or when large numbers drop out of the program after registering. To illustrate, in a major health mainte- nance organization (HMO) on the West Coast, over 70% of the eligible smokers said they would take advantage of a professionally developed self-help program if one was offered (Orleans et al., 1988). A sophisticated action-ori- ented program was developed and offered with great pub- licity. A total of 4% of the smokers signed up. As another illustration, Schmid, Jeffrey, and Hellerstedt (1989) com- pared four different recruitment strategies for home-based intervention programs for smoking cessation and weight control. The recruitment rates ranged from 1% to 5% of those eligible for smoking cessation programs and from 3% to 12% for those eligible for weight control programs.

The vast majority of addicted people are not in the action stage. Aggregating across studies and populations (Abrams, Follick, & Biener, 1988; Gottleib, Galavotti, McCuan, & McAlister, 1990; Pallonen, Fava, Salonen, & Prochaska, in press), 10%-15% of smokers are prepared for action, approximately 30%-40% are in the contem- plation stage, and 50%-60% are in the precontemplation stage. If these data hold for other populations and prob- lems, then professionals approaching communities and worksites with only action-oriented programs are likely to underserve, misserve, or not serve the majority of their target population.

Moving from recruitment rates to treatment out- comes, we have found that the amount of progress clients make following intervention tends to be a function of their pretreatment stage of change (e.g., Prochaska & DiClemente, 1992; Prochaska, Norcross, Fowler, Follick, & Abrams, 1992). Figure 2 presents the percentage of 570 smokers who were not smoking at four follow-ups over an 18-month period as a function of the stage of change before random assignment to four home-based self-help programs. Figure 2 indicates that the amount of success smokers reported after treatment was directly related to the stage they were in before treatment (Pro- chaska & DiClemente, 1992). To treat all of these smokers as if they were the same would be naive. And yet, that is what we traditionally have done in many of our treatment programs.

1105

If clients progress from one stage to the next during thefirst month of treatment, they can double their chances of taking action during the initial six months of the pro- gram. Of the precontemplators who were still in precon- templation at one month follow-up, only 3% took action by six months. For the precontemplators who progressed to contemplation at one month, 7% took action by six months. Similarly, of the contemplators who remained in contemplation at one month, only 20% took action by six months. At one month, 41% of the contemplators who progressed to the preparation stage attempted to quit by six months. These data demonstrate that treatment programs designed to help people progress just one stage in a month can double the chances of participants taking action on their own in the near future (Prochaska & DiClemente, 1992).

Mismatching Stage and Treatment

A person's stage of change provides proscriptive as well as prescriptive information on treatments of choice. Ac- tion-oriented therapies may be quite effective with indi- viduals who are in the preparation or action stages. These same programs may be ineffective or detrimental, how- ever, with individuals in precontemplation or contem- plation stages.

An intensive action- and maintenance-oriented smoking cessation program for cardiac patients was highly successful for those patients in action and ready for action. This same program failed, however, with smokers in the precontemplation and contemplation stages (Ockene, Ockene, & Kristellar, 1988). Patients in this special care program received personal counseling in the hospital and monthly telephone counseling calls for six months fol- lowing hospitalization. Of the patients who began the program in action or preparation stages, an impressive 94% were not smoking at six-month follow-up. This per- centage is significantly higher than the 66% nonsmoking rate of the patients in similar stages who received regular care for their smoking problem. The special care program had no significant effects, however, with patients in the precontemplation and contemplation stages. For patients in these stages, regular care did as well or better.

Independent of the treatment received, there were clear relationships between pretreatment stage and out- come. Twenty-two percent of all precontemplators, 43% of the contemplators, and 76% of those in action or pre- pared for action at the start of the study were not smoking six months later.

A mismatched stage effect occurred with another smoking program. An HMO-based self-help smoking cessation program for pregnant women was successful with patients prepared for action but had negligible im- pact on those in the precontemplation stage. Of the women in the preparation stage who received a series of seven self-help booklets through the mail, 38% were not smoking at the end of pregnancy (which was approxi- mately 6 months posttreatment). This was triple the 12% success rate obtained for those who received regular care

of advice and fact sheets. For precontemplators, however, 6% of those receiving special care and 6% receiving regular care were not smoking at the end of pregnancy (Ershoff, Mullen, & Quinn, 1987). These two illustrative studies portend the potential importance of matching treatments to the client's stage of change (DiClemente, 1991; Pro- chaska, 1991).

Stage Movements During Treatment

What progress do patients in formal treatment evidence on the stages of change? In a cross-sectional study we compared the stages of change scores of 365 individuals presenting for psychotherapy with 166 clients currently engaged in therapy (Prochaska & Costa, 1989). Patients entering therapy could usually be characterized as pre- pared for action because their highest score was on the contemplation scale and second highest was on the action scale. The contemplation and action scores crossed over for patients in the midst of treatment. Patients in the middle of therapy could be characterized as being in the action stage because their highest score was on the action scale. Compared with patients beginning treatment, those in the middle of therapy were significantly higher on the action scale and significantly lower on the contemplation and precontemplation scales.

We interpreted these cross-sectional data as indi- cating that, over time, patients who remained in treatment progressed from being prepared for action into taking action. That is, they shifted from thinking about their problems to doing things to overcome them. Lowered precontemplation scores also indicated that, as engage- ment in therapy increased, patients reduced their defen- siveness and resistance. The vast majority of the 166 pa- tients who were in the action stage were participating in more traditional insight-oriented psychotherapies. The progression from contemplation to action is postulated to be essential for beneficial outcome, regardless of whether the treatment is action oriented or insight ori- ented (also see Wachtel, 1977,1987).

This crossover pattern from contemplation to action was also found in a longitudinal study of a behavior ther- apy program for weight control (Prochaska, Norcross, et al., 1992). Figure 3 presents the stages of change scores at pre- and midtreatment. As a group, these subjects en- tering treatment could be characterized as prepared for action. During the first half of treatment, members of this contingent progressed into the action stage, with their contemplation scores decreasing significantly and their action scores increasing significantly.

The more clients progressed into action early in therapy, the more successful they were in losing weight by the end of treatment. The stages of change scores were the second best predictors of outcome; they were better predictors than age, socioeconomic status, problem se- verity and duration, goals and expectations, self-efficacy, and social support. The only variables that outperformed the stages of change as outcome predictors were the pro- cesses of change the clients used early in therapy.

September 1992 • American Psychologist 1106

Figure 3 A Longitudinal Comparison of Stages of Change Scores for Clients Before (Week I) and Midway Through (Week 5) a Behavioral Program for Weight Reduction

STAGES OF CHANGE-WEIGHT

35 CONTEMPLATION

3 3

ACTION

2 9

27 -

MAINTENANCE

WEEKS

N=53

Processes of Change The stages of change represent a temporal dimension that allows us to understand when particular shifts in attitudes, intentions, and behaviors occur. The processes of change are a second major dimension of the transtheoretical model that enable us to understand how these shifts occur. Change processes are covert and overt activities and ex- periences that individuals engage in when they attempt to modify problem behaviors. Each process is a broad category encompassing multiple techniques, methods, and interventions traditionally associated with disparate theoretical orientations. These change processes can be used within therapy sessions, between therapy sessions, or without therapy sessions.

The change processes were first identified theoreti- cally in a comparative analysis of the leading systems of psychotherapy (Prochaska, 1979). The processes were se- lected by examining recommended change techniques across different theories, which explains the term trans- theoretical. At least 10 subsequent principal component analyses on the processes of change items, conducted on various response formats and diverse samples, have yielded similar patterns (Norcross & Prochaska, 1986; Prochaska & DiClemente, 1983; Prochaska & Norcross, 1983; Prochaska, Velicer, DiClemente, & Fava, 1988). Ex- tensive validity and reliability data on the processes have been reported elsewhere (Prochaska et al., 1988). The processes are typically assessed by means of a self-report

instrument but have also been reliably identified in tran- scriptions of psychotherapy sessions (O'Connell, 1989).

Our research discovered that naive self-changers used the same change processes that have been at the core of psychotherapy systems (DiClemente & Prochaska, 1982, 1985; Prochaska & DiClemente, 1984). Although dis- parate theories will emphasize certain change processes, the breadth of processes we have identified appear to cap- ture basic change activities used by self-changers, psy- chotherapy clients, and mental health professionals.

The processes of change represent an intermediate level of abstraction between metatheoretical assumptions and specific techniques spawned by those theories. Gold- fried (1980, 1982), in his influential call for a rapproach- ment among the therapies, independently recommended change principles or processes as the most fruitful level for psychotherapy integration. Subsequent research on proposed therapeutic commonalities (Grencavage & Norcross, 1990) and agreement on treatment recom- mendations (Giunta, Saltzman, & Norcross, 1991) has supported Goldfried's view of change processes as the content area or level of abstraction most amenable to theoretical convergence. Although there are 250-400 dif- ferent psychological therapies (Herink, 1980; Karasu, 1986) based on divergent theoretical assumptions, we have been able to identify only 12 different processes of change based on principal components analysis. Similarly, al- though self-changers use over 130 techniques to quit smoking, these techniques can be summarized by a much smaller set of change processes (Prochaska et al., 1988).

Table 1 presents the 10 processes receiving the most theoretical and empirical support in our work, along with their definitions and representative examples of specific interventions. A common and finite set of change pro- cesses has been repeatedly identified across such diverse problem areas as smoking, psychological distress, and obesity (Prochaska & DiClemente, 1985). There are striking similarities in the frequency with which the change processes were used across these problems. When processes were ranked in terms of how frequently they were used for each of these three problem behaviors, the rankings were nearly identical. Helping relationships, consciousness raising, and self-liberation, for example, were the top three ranked processes across problems, whereas contingency management and stimulus control were the lowest ranked processes.

Significant differences occurred, however, in the ab- solute frequency of the use of change processes across problems. Individuals relied more on helping relation- ships and consciousness raising for overcoming psycho- logical distress than they did for weight control and smoking cessation. Overweight individuals relied more on self-liberation and stimulus control than did distressed individuals (Prochaska & DiClemente, 1985).

Processes as Predictors of Change

The processes have been potent predictors of change for both therapy changers and self-changers. As indicated earlier, in a behavioral weight control program, the pro-

September 1992 • American Psychologist 1107

Table 1 Titles, Definitions, and Representative Interventions of the Processes of Change

Process Definitions: Interventions

Consciousness raising

Self-reevaluation

Self-liberation

Counterconditioning

Stimulus control

Reinforcement management

Helping relationships

Dramatic relief

Environmental reevaluation

Social liberation

Increasing information about self and problem: observations, confrontations, interpretations, bibliotherapy

Assessing how one feels and thinks about oneself with respect to a problem: value clarification, imagery, corrective emotional experience

Choosing and commitment to act or belief in ability to change: decision-making therapy, New Year's resolutions, logotherapy techniques, commitment enhancing techniques

Substituting alternatives for problem behaviors: relaxation, desensitization, assertion, positive self-statements

Avoiding or countering stimuli that elicit problem behaviors: restructuring one's environment (e.g., removing alcohol or fattening foods), avoiding high risk cues, fading techniques

Rewarding one's self or being rewarded by others for making changes: contingency contracts, overt and covert reinforcement, self-reward

Being open and trusting about problems with someone who cares: therapeutic alliance, social support, self-help groups

Experiencing and expressing feelings about one's problems and solutions: psychodrama, grieving losses, role playing

Assessing how one's problem affects physical environment: empathy training, documentaries

Increasing alternatives for nonproblem behaviors available in society: advocating for rights of repressed, empowering, policy interventions

cesses used early in treatment were the single best pre- dictors of outcome (Prochaska, Norcross, et al., 1992). For self-changers with smoking, the change processes were better predictors of progress across the stages of change than were a set of 17 predictor variables, including de- mographics, problem history and severity, health history, withdrawal symptoms, and reasons for smoking (Pro- chaska, DiClemente, Velicer, Ginpil, & Norcross, 1985; Wilcox, Prochaska, Velicer, & DiClemente, 1985).

The stages and processes of change combined with a decisional balance measure were able to predict with 93% accuracy which patients would drop out prematurely from psychotherapy. At the beginning of therapy, pre- mature terminators were much more likely to be in the precontemplation stage. They rated the cons of therapy as higher than the pros, and they relied more on willpower and stimulus control than did clients who continued in therapy or terminated appropriately (Medieros & Pro- chaska, 1992).

Integrating the Processes and Stages of Change The prevailing Zeitgeist in psychotherapy is the integration of leading systems of psychotherapy (Norcross & Gold- fried, 1992; Norcross, Alford, & DeMichele, 1992). Psy- chotherapy could be enhanced by the integration of the

profound insights of psychoanalysis, the powerful tech- niques of behaviorism, the experiential methods of cog- nitive therapies, and the liberating philosophy of existen- tialism. Although some psychotherapists insist that such theoretical integration is philosophically impossible, or- dinary people in the natural environment can be re- markably effective in finding practical means of synthe- sizing powerful change processes.

The same is true in addiction treatment and re- search. There are multiple interventions but little inte- gration across theories (Miller & Hester, 1980). One promising approach to integration is to begin to match particular interventions to key client characteristics. The Institute of Medicine's (1989) report on prevention and treatment of alcohol problems identifies the stages of change as a key matching variable. A National Cancer Institute report of self-help interventions for smokers also used the stages as a framework for integrating a variety of interventions (Glynn, Boyd, & Gruman, 1990). The transtheoretical model offers a promising approach to in- tegration by combining the stages and processes of change.

A Cross-Sectional Perspective

One of the most important findings to emerge from our self-change research is an integration between the pro- cesses and stages of change (DiClemente et al., 1991;

1108 September 1992 • American Psychologist

Table 2 Stages of Change in Which Particular Processes of Change Are Emphasized

Precontemplation Contemplation

Consciousness raising

Dramatic relief

Environmental reevaluation

Self-reevaluation

Norcross, Prochaska, & DiClemente, 1991; Prochaska & DiClemente, 1983,1984). Table 2 demonstrates this in- tegration from cross-sectional research involving thou- sands of self-changers representing each of the stages of change for smoking cessation and weight loss. Using the data as a point of departure, we have interpreted how particular processes can be applied or avoided at each stage of change. During the precontemplation stage, in- dividuals used eight of the change processes significantly less than people in any of the other stages. Precontem- plators processed less information about their problems, devoted less time and energy to reevaluating themselves, and experienced fewer emotional reactions to the negative aspects of their problems. Furthermore, they were less open with significant others about their problems, and they did little to shift their attention or their environment in the direction of overcoming problems. In therapy, these would be the most resistant or the least active clients.

Individuals in the contemplation stage were most open to consciousness-raising techniques, such as obser- vations, confrontations, and interpretations, and they were much more likely to use bibliotherapy and other educa- tional techniques (Prochaska & DiClemente, 1984). Contemplators were also open to dramatic relief expe- riences, which raise emotions and lead to a lowering of negative affect if the person changes. As individuals be- came more conscious of themselves and the nature of their problems, they were more likely to reevaluate their values, problems, and themselves both affectively and cognitively. The more central their problems were to their self-identity, the more their reevaluation involved altering their sense of self. Contemplators also reevaluated the effects their addictive behaviors had on their environ- ments, especially the people with whom they were closest. They struggled with questions such as "How do I think and feel about living in a deteriorating environment that

Preparation Action Maintenance

Self-liberation

Reinforcement management

Helping relationships

Counterconditioning

Stimulus control

places my family or friends at increasing risk for disease, poverty, or imprisonment?"

Movementfrom precontemplation to contemplation and movement through the contemplation stage entailed increased use of cognitive, affective, and evaluative pro- cesses of change. Some of these changes continued during the preparation stage. In addition, individuals in prepa- ration began to take small steps toward action. They used counterconditioning and stimulus control to begin re- ducing their use of addictive substances or to control the situations in which they relied on such substances (DiClemente et al., 1991).

During the action stage, people endorsed higher lev- els of self-liberation or willpower. They increasingly be- lieved that they had the autonomy to change their lives in key ways. Successful action also entailed effective use of behavioral processes, such as counterconditioning and stimulus control, in order to modify the conditional stim- uli that frequently prompt relapse. Insofar as action was a particularly stressful stage, individuals relied increas- ingly on support and understanding from helping rela- tionships.

Just as preparation for action was essential for suc- cess, so too was preparation for maintenance. Successful maintenance builds on each of the processes that came before. Specific preparation for maintenance entailed an assessment of the conditions under which a person was likely to relapse and development of alternative responses for coping with such conditions without resorting to self- defeating defenses and pathological responses. Perhaps most important was the sense that one was becoming the kind of person one wanted to be. Continuing to apply counterconditioning and stimulus control was most ef- fective when it was based on the conviction that main- taining change supports a sense of self that was highly valued by oneself and at least one significant other.

September 1992 • American Psychologist 1109

A Longitudinal Perspective

Cross-sectional studies have inherent limitations for as- sessing behavior change, and we, therefore, undertook research on longitudinal patterns of change. Four major patterns of behavior change were identified in a two-year longitudinal study of smokers (Prochaska, DiClemente, Velicer, Rossi, & Guadagnoli, 1992): (a) Stable patterns involved subjects who remained in the same stage for the entire two years; (b) progressive patterns involved linear movement from one stage to the next; (c) regressive pat- terns involved movement to an earlier stage of change; and (d) recycling patterns involved two or more revolu- tions through the stages of change over the two-year pe- riod.

The stable pattern can be illustrated by the 27 smokers who remained in the precontemplation stage at all five rounds of data collection. Figure 4 presents these precontemplators' standardized scores (M = 50, SD = 10) for the 10 change processes being used at six-month intervals over the two-year period. All 10 processes re- mained remarkably stable over the two-year period, demonstrating little increase or decrease over time.

This figure graphically illustrates what individuals resistant to change were likely to be experiencing and doing. Eight of 10 change processes, like self-reevaluation and self-liberation, were between 0.4 and 1.4 standard deviations below the mean (i.e., 50). In brief, these subjects were doing very little to control or modify themselves or their problem behavior.

This static pattern was in marked contrast to the pattern representing people who progressed from con- templation to maintenance over the two-year study. Sig- nificantly, many of the change processes did not simply increase linearly as individuals progressed from contem- plation to maintenance. Self-reevaluation, consciousness raising, and dramatic relief—processes most associated with the contemplation stage—demonstrated significant decreases as self-changers moved through the action stage into maintenance. Conversely, self-liberation, stimulus control, contingency control, and counterconditioning— processes most associated with the action stage—evi- denced dramatic increases as self-changers moved from contemplation to action. These change processes then leveled off or decreased when maintenance was reached (Prochaska, DiClemente, et al., 1992).

Progressive self-changers demonstrated an almost ideal pattern of how change processes can be used most effectively over time. They seemed to increase the partic- ular cognitive processes most important for the contem- plation stage and then to increase more behavioral pro- cesses in the action and maintenance stages. Before over- idealizing the wisdom of self-changers, note that only 9 of 180 contemplators found their way through this pro- gressive pattern without relapsing at least once.

The longitudinal results of the 53 clients completing a behavior therapy program for weight control provide additional support for an integration of the processes and stages of change (Prochaska, Norcross, et al., 1992). As

1110

mentioned earlier, this group progressed from contem- plation to action during the 10-week therapy program. Figure 5 presents the six change processes that evidenced significant differences over the course of treatment. As predicted by the transtheoretical model, clients reported significantly greater use of four action-related change processes: counterconditioning, stimulus control, inter- personal control, and contingency management. They also increased their reliance on social liberation and de- creased their reliance on medications, wishful thinking, and minimizing threats. In other words, these clients were substituting alternative responses for overeating; they were restructuring their environments to include more stimuli that evoked moderate eating; they reduced stimuli that prompted overeating; they modified relationships to en- courage healthful eating; and they paid more attention to social alternatives that allow greater freedom to keep from overeating.

Integrative Conclusions Our search for how people intentionally modify addictive behaviors encompassed thousands of research participants attempting to alter, with and without psychotherapy, a myriad of addictive behaviors, including cigarette smok- ing, alcohol abuse, and obesity. From this and related research, we have discovered robust commonalities in how people modify their behavior. From our perspective the underlying structure of change is neither technique-ori- ented nor problem specific. The evidence supports a transtheoretical model entailing (a) a cyclical pattern of movement through specific stages of change, (b) a com- mon set of processes of change, and (c) a systematic in- tegration of the stages and processes of change.

Probably the most obvious and direct implication of our research is the need to assess the stage of a client's readiness for change and to tailor interventions accord- ingly. Although this step may be intuitively taken by many experienced clinicians, we have found few references to such tailoring before our research (Beutler & Clarkin, 1990, Norcross, 1991). A more explicit model would en- hance efficient, integrative, and prescriptive treatment plans. Furthermore, this step of assessing stage and tai- loring processes is rarely taken in a conscious and mean- ingful manner by self-changers in the natural environ- ment. Vague notions of willpower, mysticism, and bio- technological revolutions dominate their perspectives on self-change (Mahoney & Thoreson, 1972).

We have determined that efficient self-change de- pends on doing the right things (processes) at the right time (stages). We have observed two frequent mismatches. First, some self-changers appear to rely primarily on change processes most indicated for the contemplation stage—consciousness raising, self-reevaluation—while they are moving into the action stage. They try to modify behaviors by becoming more aware, a common criticism of classical psychoanalysis: Insight alone does not nec- essarily bring about behavior change. Second, other self- changers rely primarily on change processes most indi-

September 1992 • American Psychologist

Figure 4 Use of Change Processes (T scores) for 23 Smokers Who Remained in the Precontemplation Stage at Each of Five Assessment Points Over Two Years

6 4

PRECONTEMPLATORS 6 2

* - - - # CONSCIOUSNESS RAISING Q O HELPING RELATIONSHIPS

6 0 A - - S 6 L F- A LIBERATION £ & ENVIRONMENTAL REEVALUATION • - - - • DRAMATIC RELIEF O — - < > SOCIAL LIBERATION

5 8 _ V - — • • COUNTER CONDITIONING V V SELF REEVALUATION • • STIMULUS CONTROL D Q REINFORCEMENT MANAGEMENT

5 6

Process 54

O Z 5 0 LJJ I D O 48 W

4 6

4 4

4 2

4 0

38

36 h

34

3 4

ROUND

cated for the action stage—reinforcement management, We have generated a number of tentative conclusions stimulus control, counterconditioning—without the req- from our research that require empirical confirmation. uisite awareness, decision making, and readiness provided Successful change of the addictions involves a progression in the contemplation and preparation stages. They try to through a series of stages. Most self-changers and psy- modify behavior without awareness, a common criticism chotherapy patients will recycle several times through the of radical behaviorism: Overt action without insight is stages before achieving long-term maintenance. Accord- likely to lead to temporary change. ingly, intervention programs and personnel expecting

September 1992 • American Psychologist 1111

Figure 5 Change Processes That Significantly Increased or Decreased During a 10-Week Behavioral Program for Weight Reduction on a Likert Scale Ranging From 1 (Newer Use; to 5 CAImost Always Use; (N = 53)

4 r

WISHFUL THINKING

COUNTER- CONDITIONING

z SELF-LIBERATION LU Z> REINFORCEMENT

MANAGEMENT o MINIMIZING THREATS

STIMULUS CONTROL

INTERPERSONAL CONTROL

MEDICATIONS

WEEK ) WEEK 5 WEEK 10

people to progress linearly through the stages are likely to gather disappointing and discouraging results.

With regard to the processes of change, we have ten- tatively concluded that they are distinct and measurable both for self- and therapy changers. Similar processes ap- pear to be used to modify diverse problems, and similar processes are used within, between, and without psycho- therapy sessions. Dynamic measures of the processes and stages of change outperform static variables, like demo- graphics and problem history, in predicting outcome.

Competing systems of psychotherapy have promul- gated apparently rival processes of change. However, os- tensibly contradictory processes can become comple- mentary when embedded in the stages of change. Spe- cifically, change processes traditionally associated with the experiential, cognitive, and psychoanalytic persuasions are most useful during the precontemplation and con- templation stages. Change processes traditionally asso- ciated with the existential and behavioral traditions, by contrast, are most useful during action and maintenance. People changing addictive behaviors with and without therapy can be remarkably resourceful in finding practical means of integrating the change processes, even if psy- chotherapy theorists have been historically unwilling or unable to do so. Attending to effective self-changers in the natural environment and integrating effective change processes in the consulting room may be two keys to un- locking the elusive structure of how people change.

REFERENCES Abrams, D. B., Follicle, M. J., & Biener, L. (1988, November). Individual

versus group self-help smoking cessation at the workplace: Initial im- pact and 12-month outcomes. In T. Glynn (Chair), Four National Cancer Institute-funded self-help smoking cessation trials: Interim re- sults and emerging patterns. Symposium conducted at the annual meeting of the Association for the Advancement of Behavior Therapy, New York.

Beitman, B. D. (1986). The structure of individual psychotherapy. New York: Guilford Press.

Benjamin, A. (1987). The helping interview. Boston: Houghton Mifflin. Beutler, L. E., & Clarkin, J. F. (1990). Systematic treatment selection.

New York: Brunner/Mazel. Brownell, K. D., Marlatt, G. A., Lichtenstein, E., & Wilson G. T. (1986).

Understanding and preventing relapse. American Psychologist, 41, 765-782.

Cashdan, S. (1973). Interactional psychotherapy: Stages and strategies in behavioral change. New York: Grune & Stratton.

Cohen, S., Lichtenstein, E., Prochaska, J. Q , Rossi, J. S., Gritz, E. R., Carr, C. R., Orleans, C. X, Schoenbach, V. J., Biener, L., Abrams, D., DiClemente, C. G , Curry, S., Marlatt, G. A., Cummings, K. M., Emont, S. L., Giovino, G., & Ossip-Klein, D. (1989). Debunking myths about self-quitting: Evidence from 10 prospective studies of persons quitting smoking by themselves. American Psychologist, 44, 1355— ',365.

DiClemente, C. C. (1991). Motivational interviewing and the stages of change. In W. R. Miller & S. Rollnick (Eds.), Motivational interviewing: Preparing people for change (pp. 191 -202). New York: Guilford Press.

DiClemente, C. C , & Hughes, S. L. (1990). Stages of change profiles in alcoholism treatment. Journal of Substance Abuse, 2, 217-235.

DiClemente, C. C , & Prochaska, J. O. (1982). Self-change and therapy change of smoking behavior: A comparison of processes of change in cessation and maintenance. Addictive Behaviors, 7, 133-142.

DiClemente, C. C , & Prochaska, J. O. (1985). Processes and stages of change: Coping and competence in smoking behavior change. In S. Shiffman & T. A. Wills (Eds.), Coping and substance abuse (pp. 319- 343). San Diego, CA: Academic Press.

DiClemente, C. C , Prochaska, J. O., Fairhurst, S. K., Velicer, W. F., Velasquez, M. M., & Rossi, J. S. (1991). The process of smoking cessation: An analysis of precontemplation, contemplation, and prep- aration stages of change. Journal of Consulting and Clinical Psychology, 59, 295-304.

DiClemente, C. C , Prochaska, J. Q , & Gilbertini, M. (1985). Self-efficacy and the stages of self-change of smoking. Cognitive Therapy and Re- search, 9, 181-200.

Donovan, D. M., & Marlatt, G. A. (Eds.). (1988). Assessment of addictive behaviors: Behavioral, cognitive, and physiological procedures. New York: Guilford Press.

Dryden, W. (1986). Eclectic psychotherapies: A critique of leading ap- proaches. In J. C. Norcross (Ed.), Handbook of eclectic psychotherapy. New York: Brunner/Mazel.

Egan, G. (1975). The skilled helper: A model for systematic helping and interpersonal relating. Monterey, CA: Brooks/Cole.

Ershoff, D. H., Mullen, P. D., & Quinn, V. (1987, December). Self-help interventions for smoking cessation with pregnant women. Paper pre- sented at the Self-Help Intervention Workshop of the National Cancer Institute, Rockville, MD.

Giunta, L. C , Saitzman, N., & Norcross, J. C. (1991). Whither inte- gration? An exploratory study of contention and convergence in the Clinical Exchange. Journal oflntegrative and Eclectic Psychotherapy, 10, 117-129.

Glynn, T. J., Boyd, G. M., & Gruman, J. C. (1990). Essential elements of self-help/minimal intervention strategies for smoking cessation. Health Education Quarterly, 17, 329-345.

Goldfried, M. R. (1980). Toward the delineation of therapeutic change principles. American Psychologist, 35, 991-999.

Goldfried, M. R. (1982). Converging themes in psychotherapy. New York: Springer.

Gottlieb, N. H., Galavotti, C , McCuan, R. S., & McAlister, A. L. (1990). Specification of a social cognitive model predicting smoking cessation in a Mexican-American population: A prospective study. Cognitive Therapy and Research, 14, 529-542.

1112 September 1992 • American Psychologist

Grencavage, L. M , & Norcross, J. C. (1990). Where are the common- alities among the therapeutic common factors? Professional Psychol- ogy: Research and Practice, 21, 372-378.

Herink, R. (Ed.). (1980). The psychotherapy handbook. New York: Me- ridian.

Horn, D. & Waingrow, S. (1966). Some dimensions of a model for smoking behavior change. American Journal of Public Health, 56, 21-26.

Institute of Medicine. (1989). Prevention and treatment of alcohol prob- lems: Research opportunities. Washington, DC: National Academy Press.

Kanfer, F. H. (1986). Implications of a self-regulation model of therapy for treatment of addictive behaviors. In W. R. Miller & N. Heather (Eds.), Treating addictive behaviors: Processes of change (pp. 29-50). New York: Plenum Press.

Karasu, T. B. (1986). The specificity versus nonspecificity dilemma: To- ward identifying therapeutic change agents. American Journal of Psy- chiatry, 143, 687-695.

Lam, C. S., McMahon, B. T , Priddy, D. A., & Gehred-Schutlz, A. (1988). Deficit awareness and treatment performance among traumatic head injury adults. Brain Injury, 2, HS-lAl.

Lambert, M. J., Shapiro, D. A., & Bergin, A. E. (1986). The effectiveness of psychotherapy. In S. L. Garfield & A. E. Bergin (Eds.), Handbook of psychotherapy and behavior change (3rd ed.). New \brk: Wiley.

Mahoney, M. J., & Thoreson, C. E. (1972). Behavioral self-control: Power to the person. Educational Researcher, I, 5-7.

Marlatt, G. A., Baer, J. S., Donovan, D. M., & Divlahan, D. R. (1988). Addictive behavior: Etiology and treatment. Annual Review of Psy- chology, 39, 223-252.

Marlatt, G. A., & Gordon, J. R. (1985). Relapse prevention: A self-control strategy for the maintenance of behavior change. New York: Guilford Press.

McConnaughy, E. A., DiClemente, C. C , Prochaska, J. Q , & Velicer, W. F. (1989). Stages of change in psychotherapy: A follow-up report. Psychotherapy, 26, 494-503.

McConnaughy, E. A., Prochaska, J. Q , & Velicer, W. F. (1983). Stages of change in psychotherapy: Measurement and sample profiles. Psy- chotherapy, 20, 368-375.

Medieros, M., & Prochaska, J. O. (1992). Predicting premature termi- nation from psychotherapy. Manuscript submitted for publication.

Miller, W. R., & Hester, R. R. (1980). Treating the problem drinker: Modern approaches. In W. R. Miller (Ed.), The addictive behaviors: Treatment of alcoholism, drug abuse, smoking and obesity (pp. 11- 141). Oxford, England: Pergamon Press.

Miller, W. R., & Hester, R. R. (1986). The effectiveness of alcoholism treatment. In W. R. Miller & N. Heather (Eds.), Treating addictive behaviors: Processes of change (pp. 121-174). New \brk: Plenum Press.

Norcross, J. C. (1991). Prescriptive matching in psychotherapy: Psy- choanalysis for simple phobias? Psychotherapy, 28, 439-443.

Norcross, J. C , Alford, B. A., & DeMichele, J. T. (1992). The future of psychotherapy: Delphi data and concluding observations. Psycho- therapy, 29, 150-158.

Norcross, J. C , & Goldfried, M. R. (Eds.). (1992). Handbook of psy- chotherapy integration. New York: Basic Books.

Norcross, J. G , & Prochaska, J. O. (1986). Psychotherapist heal thyself: 1. The psychological distress and self-change of psychologists, coun- selors, and laypersons. Psychotherapy, 23, 102-114.

Norcross, J. C , Prochaska, J. Q , & DiClemente, C. C. (1991). The stages and processes of behavior change: Two replications with weight control. Manuscript submitted for publication.

Norcross, J. C , Ratzin, A. C , & Payne, D. (1989). Ringing in the New Year: The change processes and reported outcomes of resolutions. Addictive Behaviors, 14, 205-212.

Norcross, J. C , & Vangarelli, D. J. (1989). The resolution solution: Lon- gitudinal examination of New Year's change attempts. Journal of Substance Abuse, I, 127-134.

Ockene, J., Ockene, I., & Kristellar, J. (1988). The coronary artery smoking intervention study. Worcester, MA: National Heart Lung Blood Institute.

O'Connell, D. (1989). An observational coding scheme for therapists' processes of change. Unpublished doctoral dissertation, University of Rhode Island, Kingston.

September 1992 • American Psychologist

Orford, J. (1985). Excessive appetites: A psychological view of addictions. New York: Wiley.

Orleans, C. T , Schoenback, V. J., Salmon, M. A., Wagner, E. A., Pearson, D. C , Fiedler, J., Quade, D., Porter, C. Q., & Kaplan, B. A. (1988, November). Effectiveness of self-help quit smoking strategies. In T. Glynn (Chair), Four National Cancer Institute-funded self-help smok- ing cessation trials: Interim results and emerging patterns. Symposium presented at the annual meeting of the Association for the Advance- ment of Behavior Therapy, New York.

Pallonen, U. E., Fava, J. L., Salonen, J. T , & Prochaska, J. O. (in press). Readiness for smoking change among middle-aged Finnish men: The KUOPIO CVD risk factor trial. Addictive Behaviors.

Prochaska, J. O. (1979). Systems of psychotherapy: A transtheoretical analysis. Homewood, IL: Dorsey Press.

Prochaska, J. O. (1991). Prescribing to the stages and levels of change. Psychotherapy, 28, 463-468.

Prochaska, J. O , & Costa, A. (1989). A cross-sectional comparision of stages of change for pre-therapy and within-therapy clients. Unpub- lished manuscript, University of Rhode Island, Kingston.

Prochaska, J. Q , & DiClemente, C. C. (1982). Transtheoretical therapy: Toward a more integrative model of change. Psychotherapy: Theory, Research and Practice, 20, 161-173.

Prochaska, J. Q , & DiClemente, C. C. (1983). Stages and processes of self-change in smoking: Toward an integrative model of change. Journal of Consulting and Clinical Psychology, 5, 390-395.

Prochaska, J. Q , & DiClemente, C. C. (1984). The transtheoretical ap- proach: Crossing traditional boundaries of change. Homewood, IL: Dorsey Press.

Prochaska, J. O , & DiClemente, C. C. (1985). Common processes of change in smoking, weight control, and psychological distress. In S. Shiftman & T. Wills (Eds.), Coping and substance abuse (pp. 345- 363). San Diego, CA: Academic Press.

Prochaska, J. Q , & DiClemente, C. C. (1986). Toward a comprehensive model of change. In W. R. Miller & N. Heather (Eds.), Treating ad- dictive behaviors: Processes of change (pp. 3-27). New \brk: Plenum Press.

Prochaska, J. Q , & DiClemente, C. C. (1992). Stages of change in the modification of problem behaviors. In M. Hersen, R. M. Eisler, & P. M. Miller (Eds.), Progress in behavior modification (pp. 184-214). Sycamore, IL: Sycamore Press.

Prochaska, J. Q , DiClemente, C. C , Velicer, W. F., Ginpil, S., & Norcross, J. C. (1985). Predicting change in smoking status for self-changers. Addictive Behaviors, 10, 395-406.

Prochaska, J. Q , DiClemente, C. C , Velicer, W. F., Rossi, J. S., & Guad- agnoli, E. (1992). Patterns of change in smoking cessation: Between variable comparisons. Manuscript submitted for publication.

Prochaska, J. O , & Norcross, J. C. (1983). Psychotherapists' perspectives on treating themselves and their clients for psychic distress. Professional Psychology: Research and Practice, 14, 642-655.

Prochaska, J. O., Norcross, J. C , Fowler, J. L., Follick, M. J., & Abrams, D. B. (1992). Attendance and outcome in a work-site weight control program: Processes and stages of change as process and predictor variables. Addictive Behaviors, 17, 35-45.

Prochaska, J. O , Velicer, W. F., DiClemente, C. C , & Fava, J. S. (1988). Measuring processes of change: Applications to the cessation of smoking. Journal of Consulting and Clinical Psychology, 56, 520- 528.

Rice, L. N., & Greenberg, L. (Eds.). (1984). Patterns of change. New York: Guilford Press.

Roizen, R., Cahaland, D., & Shanks, R. (1978). Spontaneous remission among untreated problem drinkers. In D. Randell (Ed.), Longitudinal research on drug use: Empirical findings and methodological issues. Washington, DC: Hemisphere.

Schachter, S. (1982). Recidivism and self-cure of smoking and obesity. American Psychologist, 37, 436-444.

Schmid, T. L., Jeffrey, R. W , & Hellerstedt, W. L. (1989). Direct mail recruitment to home-based smoking and weight control programs: A comparison of strengths. Preventive Medicine, 18, 503-517.

Shapiro, S., Skinner, E., Kessler, L., Van Korff, M., German, P., Tischler, G., Leon, P., Bendham, L., Cottier, L., & Regier, D. (1984). Utilization of health and mental health services. Archives of General Psychiatry, 41, 971-978.

1113

Smith, M. L., Glass, G. V., & Miller, T. I. (1980). The benefits of psy- chotherapy. Baltimore: John Hopkins University.

Tuchfeld, B. (1981). Spontaneous remission in alcoholics: Empirical ob- servations and theoretical implications. Journal of Studies on Alcohol, 42, 626-641.

Velicer, W. F., DiClemente, C. C , Prochaska, J. Q, & Brandenburg, N. (1985). A decisional balance measure for assessing and predicting smoking status. Journal of Personality and Social Psychology, 48, 1279-1289.

Veroff, J., Douvan, E., & Kulka, R. A. (1981a). The inner America. New York: Basic Books.

Veroff, J., Douvan, E., & Kulka, R. A. (1981b). Mental health in America. New York: Basic Books.

Wachtel, P. L. (1977). Psychoanalysis and behavior therapy: Toward an integration. New York: Basic Books.

Wachtel, P. L. (1987). Action and insight. New York: Guilford Press. Wilcox, N., Prochaska, J. Q, Velicer, W. E, & DiClemente, C. C. (1985).

Client characteristics as predictors of self-change in smoking cessation. Addictive Behaviors, 40, 407-412.

Correction to Williams

The article "Exploitation and Inference: Mapping the Damage From Therapist-Patient Sexual Involvement," by Martin H. Williams (American Psychologist, 1992, Vol. 47, No. 3, pp. 412-421), contained an error on page 419. The sentence "In this case, the odds that a patient will become sexually involved with his or her psychoanalyst are 1 in 1,129 or a likelihood of 0.9%" should read "In this case, the odds that a patient will become sexually involved with his or her psychoanalyst are 1 in 1,129 or a likelihood of 0.09%."

1114 S e p t e m b e r 1992 • A m e r i c a n Psychologist