Twelve-Step and Cognitive-Behavioral Treatment for Substance Abuse A Comparison of Treatment Effectiveness

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1 Page 1 of 17 Journal of Consulting and Clinical Psychology 1997, Vol. 65, No. 2, Copyright 1997 by the American Psychological Association X/$3.00 Twelve-Step and Cognitive-Behavioral Treatment for Substance Abuse A Comparison of Treatment Effectiveness Paige Crosby Ouimette Program Evaluation and Resource Center and HSR & D John W. Finney Program Evaluation and Resource Center and HSR & D Rudolf H. Moos Program Evaluation and Resource Center and HSR & D Paige Crosby Ouimette, Program Evaluation and Resource Center and HSR & D, Center for Health Care Evaluation, Veterans Affairs Palo Alto Health Care System, Palo Alto, California; John W. Finney and Rudolf H. Moos, Program Evaluation and Resource Center and HSR & D, Center for Health Care Evaluation, Veterans Affairs Palo Alto Health Care System, Palo Alto, California, and Stanford University Medical Center. This project benefited from the cooperation and efforts of an impressive number of individuals. Paul Errera, Thomas Horvath, Richard Suchinsky, and Karen Boies provided helpful guidance and support from the Department of Veterans Affairs Mental Health Strategic Health Group at the Veterans Affairs National Headquarters, Washington, DC. At each of the participating Veterans Affairs Medical Centers, (VAMCs) local coordinators organized the local data collection process, hired local staff, and resolved various local problems, and project assistants collected extensive data on patients at intake, discharge, and follow-up. These individuals and their VAMC locations were as follows: Nancy D'Abadie, Colin Quinn, Karen Drexler, and Faheemah Muhammad, Atlanta, Georgia; James Robyak and Timothy Shaver, Bay Pines, Florida; Laure Buydens, John Toma, and Michael Rothman, Brooklyn, New York; Kay Manley, Norman Kruedelbach, Loreen Rugle, Ronald Campbell, Alex Olivera, and Bart Vrtunski, Cleveland, Ohio; Michael Clayton, Marilyn Krabbe, and Susan Nunamaker, Danville, Illinois; Usha Malkerneker and Karen Scanlan, Hines, Illinois; Jan Campbell and Gretchen Young, Kansas City, Missouri; Jeffrey Wilkins and Martha Lewis, (West) Los Angeles, California; Paul Mushala, Robert Murray, Ervin "Buddy" Wright, and Sandra Scott, Memphis, Tennessee; Carl Isenhart, Daniel Silversmith, and Steve Van Krevelen, Minneapolis, Minnesota; Robert Malow, Jose Pena, Patricia Sutker, Lester Barnett, Stacey Cunningham, Dee Martin, and Alicia Borges, New Orleans, Louisiana; Frank Crow and Cheryl Keesee, Richmond, Virginia; and Rex Turner, Steve Ross, Harold Price, Lisa Himonas, and Tracy Hed, Salt Lake City, Utah. At the Program Evaluation and Resource Center, several dedicated individuals provided invaluable assistance on this project: Peg Maude-Griffin helped to develop and initiate the project, and Charlotte Noyes coordinated the project thereafter; Courtney Ahrens, Michelle Birch, Adam Coutts, Kristian Gima, Todd McCallum, Jennifer Noke, Katrine VanderWeide, and Amy Wender monitored data collection, managed data, and performed statistical analyses. This evaluation would not have been possible without the cooperation of almost 3,700 veterans. We express our gratitude to these veterans for their participation and commitment to improving substance abuse treatment for other veterans. Keith Humphreys and Kathleen Schutte provided helpful comments on this article. Correspondence may be addressed to Paige Crosby Ouimette, Menlo Park Division (152),Veterans Affairs Palo Alto Health Care System,795 Willow Road,Menlo Park,California,94025,

2 Page 2 of 17 Received: April 9, 1996 Revised: August 3, 1996 Accepted: August 28, 1996 ABSTRACT The comparative effectiveness of 12-step and cognitive-behavioral (C-B) models of substance abuse treatment was examined among 3,018 patients from 15 programs at U.S. Department of Veterans Affairs Medical Centers. Across program types, participants showed significant improvements in functioning from treatment admission to a 1-year follow-up. Although 12-step patients were somewhat more likely to be abstinent at the 1- year follow-up, 12-step, C-B, and combined 12-Step-C-B treatment programs were equally effective in reducing substance use and improving most other areas of functioning. The finding of equal effectiveness was consistent over several treatment subgroups: Patients attending the "purest" 12-step and C-B treatment programs, and patients who had received the "full dose" of treatment. Also, patients with only substance abuse diagnoses, those with concomitant psychiatric diagnoses, and patients who were mandated to treatment showed similar improvement at the 1-year follow-up, regardless of type of treatment received. These data provide important new evidence supporting the effectiveness of 12-step treatment. In the U.S. health care system, growing emphasis is being placed on monitoring treatment outcomes and identifying effective mental health treatment. The field of substance abuse treatment has similarly moved toward outcome accountability ( Miller et al., 1995 ). Unfortunately, the most widely used substance abuse intervention, the 12-step program, has little comparative research on its effectiveness in either professional or mutual help settings. However, studies of participation in 12-step groups as part of aftercare (e.g., Emrick, Tonigan, Montgomery, & Little, 1993 ; Tonigan, Toscova, & Miller, 1996 ) support the association of 12-step treatment or involvement with abstinence. In contrast, numerous evaluations of cognitive-behavioral (C-B) interventions for addictive behaviors have been conducted and support its effectiveness relative to alternative and control treatments (e.g., Finney & Monahan, 1996 ; Holder, Longabaugh, Miller, & Rubonis, 1991 ; Miller et al., 1995 ). Accordingly, a comparison of 12-step and C-B substance abuse programs provides a rigorous test of 12-step treatment effectiveness. To date, there have been only two controlled trials comparing 12-step and C-B interventions; one focused on alcohol-dependent outpatients ( Project MATCH Research Group, 1996 ) and the other on cocaine-dependent outpatients ( Wells, Peterson, Gainey, Hawkins, & Catalano, 1994 ). No comparison of these interventions as they occur in the natural clinical situation with a broad range of patients has been conducted. This article presents data from a naturalistic multisite evaluation of substance abuse treatment programs based on 12-step and C-B approaches. Twelve-Step and C-B Treatment for Substance Abuse Twelve-step and C-B interventions are two of the most widely used models of substance abuse treatment ( McCrady, 1994 ; Peterson, Swindle, Paradise, & Moos, 1994 ). However, these two approaches have frameworks for understanding the etiology, treatment, and recovery from substance abuse that are divergent in many respects ( McCrady, 1994 ; Morgenstern & McCrady, 1992 ). Traditional 12-step approaches developed from a self-help approach and combine the elements of Alcoholics-Narcotics-Cocaine Anonymous with the disease model of addiction. A fundamental assumption is that substance abuse is the result of an underlying biological or psychological vulnerability that leads to loss of control of the abused substance. Individuals receiving 12-step

3 Page 3 of 17 treatment are encouraged to accept the disease model of addiction, an alcoholic or addict identity, and abstinence as their treatment goal, and they are expected to become involved in 12-step activities (i.e., going to 12-step meetings, getting a sponsor, and working the steps). The C-B approach to substance abuse treatment developed from social learning theory and clinical research. An underlying assumption of the C-B model is that substance abuse is a learned, maladaptive behavior. Substance abuse is hypothesized to be initiated and maintained by distorted beliefs about the power of the abused substance and the reinforced use of the substance to cope with stressful situations. C-B interventions usually target two areas: (a) changing distorted thinking about the abused substances, and (b) increasing adaptive coping responses. Only two empirical studies have directly compared 12-step and C-B interventions for substance abuse. Project MATCH, a multisite clinical trial of 12-step facilitation, C-B coping skills training, and motivational enhancement therapy, found that outpatients in 12-step and C-B treatments improved substantially but had comparable global alcohol use outcomes at several follow-ups ( Project MATCH Research Group, 1996 ). In a randomized clinical trial, Wells et al. (1994) examined the relative efficacy of 12-step and relapse prevention psychotherapy groups for cocainedependent outpatients. Although participants in both conditions reduced their cocaine, alcohol, and marijuana use from pretreatment to posttreatment, no differences emerged between treatment groups on posttreatment cocaine or marijuana use. However, participants in the two groups did differ on one outcome: The 12-step patients showed significantly greater increases in their alcohol use from 12 weeks to the 6-month follow-up than the relapse prevention patients. One methodological issue may limit the interpretability of these findings: random assignment to 12- step treatment. It has been proposed that random assignment to 12-step groups changes the nature of 12-step intervention, which is based on voluntary participation, and may lessen its effectiveness (for a discussion of this issue, see Humphreys & Rappaport, 1994 ). The Present Study Our primary goal was to compare the effectiveness of 12-step and C-B treatment for substance abuse using a naturalistic design. Patients attending one of 15 Department of Veterans Affairs (VA) substance abuse treatment programs were assessed with a comprehensive assessment battery at admission and at approximately 1 year postdischarge. We focused on the comparative effectiveness of 12-step and C-B treatments and programs that used both of these approaches on substance use, psychiatric, legal, employment, and residential outcomes. An additional focus grew out of the dramatic changes in the characteristics of substance abuse patients that have been noted in recent years. Individuals seeking substance abuse services are more likely to receive comorbid psychiatric diagnoses ( Helzer & Pryzbeck, 1988 ; Piette, Baisden, & Moos, 1995 ; Regier et al., 1990 ; Ross, Glaser, & Germanson, 1988 ) and are increasingly referred from the criminal justice system ( Weisner, 1990 ). Current thinking in treating dually diagnosed individuals emphasizes integrated treatment of both substance abuse and the psychiatric problem, and pharmacotherapy, if needed ( N. S. Miller, 1994 ; Minkoff, 1994 ; Swindle, Phibbs, Paradise, Recine, & Moos, 1995 ). However, 12-step philosophy focuses on substance abuse as the primary problem and discourages use of psychotropic medications for psychiatric problems ( Buxton, Smith, & Seymour, 1987 ; Zweben & Smith, 1989 ). We hypothesized that 12-step programs may be more effective with patients with only substance-related

4 Page 4 of 17 diagnoses and less effective with dually diagnosed patients. The effectiveness of 12-step groups may be compromised by "nonvoluntary," or coerced, attendance (see Humphreys & Rappaport, 1994 ; Weisner, 1990 ). We examined whether 12-step treatment in a professional setting may be less effective for patients who were legally mandated to receive substance abuse treatment. Participants Method Patients in 15 VA inpatient programs were asked to participate in this VA-approved evaluation after they had completed medical detoxification (detox) and were admitted to the treatment program. Women were excluded from the project because of their small numbers ( n = 64). In each program, consecutive admissions were approached, unless it was determined that the patient volume would be in excess of data collection capabilities. If so, a sampling procedure was implemented in which every other admission or every third admission was recruited. A total of 4,193 patients were invited to participate (90% of those eligible); the other 10% left the program before completing detox or were not invited to participate because of scheduling problems. Of these 4,193 patients, 494 (12%) refused to participate, leaving a final intake sample of 3,699 patients. These latter patients completed the Intake Information Form (IIF), which assessed background information, physical and mental health, alcohol and drug use and related variables, and psychosocial functioning. Follow-Up An attempt was made to contact each patient 12 months postdischarge to complete the Follow-Up Information Form (FIF), a questionnaire assessing identical content areas as the IIF. The average follow-up occurred 13.2 months ( SD = 2.8) after the patients left the program. For convenience, we refer to this as a "1-year" follow-up. A total of 86 participants died during the follow-up period. Of the remaining 3,613 patients, 3,018 (83.5%) completed the follow-up. A total of 595 (16.5%) refused to participate or were not located. We compared follow-up participants and nonparticipants (excluding deceased patients) on age, education, ethnicity, income, employment status and symptoms of alcohol dependence at intake to treatment. Groups did not differ significantly on any of the measures. Follow-up rates among participants differed among the three program types, &khgr; 2 (2, N = 3699) = 21.59, p <.001: C-B (85%) had a higher follow-up rate than 12-step (78%) and mixed 12- step/c-b programs (81%). The 3,018 patients who completed both the intake and follow-up assessments were, on average, 43 years of age ( SD = 9.63) and had a high school education ( M = 12.72; SD = 1.76); the majority was unemployed (76.2%; N = 2,301). Patients average annual income was approximately $10,670 ( SD = 9,421.32). About 49% of the men were African American, 46% were Caucasian, 3% were Hispanic- Latino, and the remaining 2% were Asian, Native American, or other. Only 19% of the men were married, 39% were divorced, 23% were never married, 17% were separated, and 2% were widowed. Most patients completed the FIF as a self-administered survey that was returned through the mail (92%; N = 2,782) or at their site (about 1%; N = 21); the remaining participants completed the forms through an inperson or telephone interview (about 6%; N = 180). FIFs were checked for missing data and coded by trained research assistants who, if needed, recontacted the patient when possible, to obtain missing information and resolve ambiguities in the patients responses. Selection of Programs and Designation-Verification of Program Type

5 Page 5 of 17 Fifteen VA Medical Center substance abuse treatment programs were selected from a larger pool of 174 programs based on the following criteria: 12-step, C-B, or mixed 12-step-C-B treatment orientation, large patient pool and stable patient census, and geographic dispersion across the United States. Information on programs was gathered through program proposals submitted to the VA National Headquarters for enhanced substance abuse treatment funding, informational telephone interviews, and data from the VA Patient Treatment File (a systemwide database that abstracts information on each discharge from a VA facility). After the potential programs were narrowed down using this information, site visits were conducted. A PhD-level clinical psychologist, extensively trained in the assessment and treatment of substance abuse, spent days at each site, observing one or more treatment groups and informally interviewing the staff about their treatment orientation and treatment intensity. The assessment of treatment intensity ensured comparability of programs on amount of treatment offered. The final designation of the treatment orientation of each program was based on empirical data. Semistructured phone interviews with each program director were conducted. Information was gathered regarding treatment, including percent time spent in 12-step and C-B activities. The directors were also asked to fill out the Drug and Alcohol Treatment Inventory (DAPTI: Peterson et al., 1994 ; Swindle, Peterson, Paradise, & Moos, 1995 ), which includes questions about goals and activities relevant to both 12-step and C-B treatment. Based on this information, five programs were categorized as 12-step, five programs as C-B, and five programs as mixed 12-step/C-B treatment. Table 1 presents the data from the program directors interviews and DAPTI scores. We verified these program designations using data provided by program staff on the DAPTI and the short version of the Understanding of Substance Use Scale (SUSS; Humphreys, Greenbaum, Noke, & Finney, 1996 ), an adapted version of the Understanding of Alcoholism Scale ( Moyers & Miller, 1993 ). Individual dimensions of the SUSS measure adherence to (a) the disease model and (b) the psychosocial model of substance abuse. As expected, staff in 12-step programs reported significantly more treatment goals, activities, and beliefs consistent with a 12-step orientation than did staff in C-B programs. Similarly, staff in C-B programs were significantly more likely to report treatment goals, activities, and beliefs consistent with a C-B orientation than were staff in 12-step programs. Staff in the three program types did not differ on psychosocial model beliefs, probably reflecting the emphasis on social and environmental change in all programs. Staff in mixed 12-step/C-B programs scored in between the other two groups on all dimensions (see Table 1 ). Description of Treatment Programs Programs had a 21- to 28-day desired length of stay, used individual and group therapy to assist patients in meeting their treatment goals, and were multidisciplinary in staffing. All programs expected aftercare participation and provided referrals to both outpatient treatment and communitybased self-help organizations. Twelve-step programs emphasized treatment activities such as 12-step meetings in the community and hospital, and psychotherapy groups covering topics such as working the steps, the Big Book, and writing an autobiography. Treatment targeted the patient's acceptance of an alcoholic-addict identity, acknowledgment of a loss of control-powerlessness over the abused substance, and adherence to abstinence as a treatment goal. C-B programs required participation in relapse prevention groups, cognitive skills training,

6 Page 6 of 17 behavioral skills training, abstinence skills training, and small C-B therapy groups. The goals of C-B treatment were to teach more adaptive ways of coping, enhance the patient's sense of self-efficacy to cope with high-risk relapse-inducing situations, and to modify the patient's expectations of the abused substances effects such that they were more realistic and appropriate. Outcome Measures Selected scales and items were taken from the IIF and the FIF. All questions, unless otherwise noted, were asked in reference to the prior 3 months. Our rationale for a 3-month interval was twofold: (a) It is long enough to assess more than the atypical patterns of functioning that may immediately precede treatment entry; and (b) it is short enough to minimize problems in recall ( Cooper, Sobell, Maisto, & Sobell, 1980 ). The following variables were used in the present analyses. Substance Use Variables Alcohol consumption.. Alcohol consumption was assessed using questions from the Health and Daily Living Form (HDL; Moos, Cronkite, & Finney, 1990 ). Participants were asked to indicate their usual and largest amounts of beer, wine, and hard liquor consumed per day. These quantities were converted to ounces of ethanol and summed. Frequency of use was assessed by having participants indicate how often they drank their usual and largest amounts of beer, wine, and hard liquor on a 5-point scale (i.e., never; less than once a week; 1-3 days a week; 4-6 days a week; every day). These scores were converted to percent time per week and summed. From these variables, an alcohol consumption measure was created that reflected average ounces of ethanol consumed per day, factoring in heavy drinking days (i.e. a quantity-frequency-variability index; see Room, 1990 ; Sobell & Sobell, 1992 ). The presence or absence of alcohol dependence was assessed through nine items designed to measure criteria for alcohol dependence from the Diagnostic and Statistical Manual of Mental Disorders (3rd edition, revised; DSM-III-R ; American Psychiatric Association 1987 ). Examples of items include "During the past three months, how often did you.&numsp;.&numsp;.&numsp;have more to drink than you expected?, or.&numsp;.&numsp;.&numsp;take a drink to relieve a hangover, or to keep from going into withdrawal?" Each item was rated on a 5-point scale ranging from 0 ( never ) to 4 ( almost every day ), and each symptom was counted as clinically significant if patients reported that it occurred once a week or more. In line with DSM-III-R, the presence of three or more clinically significant symptoms was used as a cutoff to indicate the presence or absence of alcohol dependence. Problems from substance use. The absence of problems from substance use was assessed by 18 items scored on a 5-point scale (0 = never to 4 = often ) that measured a comprehensive array of standard problems that may result from alcohol and drug use, including health, legal, monetary, occupational, intra- and interpersonal difficulties, and residential problems. Patients were scored 1 if they reported no problems from substance use and 0 if they reported any problems as a result of their substance use. Remission. To be classified as in remission, a patient had to meet two criteria derived from the measures described above: (a) consumption of three ounces or less of ethanol on a usual drinking day; (b) no problems resulting from alcohol and drug use; and (c) no illicit drug use. The latter was assessed using items adapted from the Treatment Outcome Prospective Study inventories ( Hubbard, Marsden,

7 Page 7 of 17 Cavanaugh, & Ginzburg, 1989 ), which asked participants to indicate the frequency of use of various illicit drugs on a 5-point scale ranging from 0 ( never ) to 4 ( every day ). Our rationale for including nonproblem drinkers in the remitted category was twofold. First, some patients did not have alcohol use disorders before treatment and may have continued to drink moderately without problems after treatment. Second, some patients with alcohol use disorders may have resumed drinking at a moderate level without problems or negative consequences ( W. R. Miller, 1983 ). Abstinent. To be classified as abstinent, a patient had to meet three criteria derived from the measures described above: (a) no alcohol consumption; (b) no illicit drug use; and (c) no problems resulting from alcohol and drug use. We implemented several data collection strategies suggested by Babor, Stephens, and Marlatt (1987) to minimize the potential for false reports. Every participant was assured of confidentiality and was notified that the project assistant at his site was not part of the clinical staff and that his participation would have no negative consequences on his current or subsequent treatment. The purpose of the research was clearly stated, and its relevance to other veterans health care was emphasized. Throughout the study, the need for accurate responses was underscored to the participants. Attempts were made to verify patients self-report using biological tests (e.g., urine-blood-breath samples) collected at VA Medical Centers during nonrandom patient visits (e.g., for a medical appointment) in the 1-year follow-up. Patients gave consent for use of information from their medical records for internal program evaluation when they entered the VA health care system for health services. Project assistants at each site obtained available test results from patient medical charts. We identified 230 men who had received an alcohol/drug test in the same 3-month period (we included drug tests collected one week after the date of the self-report) as their self-report data. Patient reports of abstinence from alcohol and drugs were significantly associated with a negative alcohol or drug test (all p s <.001). In the 78 men tested for alcohol use, 35 of 37 men (95%) reporting abstinence from alcohol use had a negative test for alcohol use. In the 230 men with drug test data (including opiates, cocaine, amphetamines, sedative-tranquilizers, and marijuana), 144 of 167 men (86%) reporting abstinence from drug use had a negative test. Agreement rates for respondents reporting no use of individual drugs ranged from 93% for tranquilizer use to 100% for amphetamine use. In addition, the rates of biological test-self-report agreement for alcohol and drug use did not differ among the three program types. These data are generally consistent with data from other studies supporting the validity of self-reports of alcohol and drug use given the longer time interval for self-report data used here (for a review, see Babor et al., 1987 ). Taken together, the conditions under which data were collected and the biological test data support the validity of the self-report data. Psychosocial Variables Psychological status. Psychological functioning was measured by items from the Brief Symptom Inventory (BSI; Derogatis & Melisaratos, 1983 ). The BSI is a self-report inventory designed to assess psychological symptoms in clinical and nonclinical samples. The BSI has been used in previous research with alcohol and drug abuse patients (e.g., Buckner & Mandell, 1990 ; Royce & Drude, 1984 ; Verinis, Wetzal,

8 Page 8 of 17 Vanderporten, & Lewis, 1986 ). In the present study, the presence or absence of clinically significant depression and anxiety was examined using a T score cutoff of 65 and male nonpatient normative data. Legal status (not arrested). Patients were asked to indicate their legal status in the past 12 months. Patients were scored as 1 if they indicated no arrests, or 0 if they reported an arrest. Employment status (employed). Patients were asked if they were employed at the time of admittance to their program and at the 1- year follow-up. Patients were scored 1 if they were employed full- or part-time and 0 if they were not employed. Residential status (not incarcerated/homeless). Patients reported where they had been living for the most of the past 12 months. Patients were coded 1 if they were living in a house, apartment, rooming house, halfway house, hospital, or shelter and 0 if they were incarcerated or homeless. Other Measures Precontemplation is a subscale of the Stages of Change Readiness and Treatment Eagerness Scale ( Miller & Tonigan, 1996 ). The latter was adapted from the Stages of Change Inventory ( DiClemente & Hughes, 1990 ). Higher scores on this subscale indicate lower levels of motivation for change, which is hypothesized to predict poorer treatment outcomes. Coefficient alpha for this four-item precontemplation subscale was.59 in the intake sample data ( n = 3,693). Treatment Completion Patient's length of stay was recorded on the Treatment Experiences Form (TEF) by the project assistant at each site. Using this information, treatment completion was determined for each patient who also completed the 1-year follow-up. Patients were required to stay 100% of their programs expected length of stay (21 or 28 days) or longer to be considered as a recipient of a "full dose" of treatment ( n = 1,981). Psychiatric Diagnoses Patients diagnoses were obtained using the VA Patient Treatment File (PTF). The PTF is a systemwide database that abstracts information on each discharge from a VA facility; it includes patients discharge diagnoses based on the International Classification of Diseases-9th Revision (ICD-9-CM; United States National Center for Health Statistics, 1988 ). These diagnoses reflect current functioning. Using this information, patients who completed the 1-year follow-up were grouped into those with only substance-related (ICD-9-CM alcohol or drug abuse/dependence; N = 1,910), and those with an additional nonsubstance-related psychiatric diagnoses (including affective, psychotic, anxiety, and personality disorders; N = 1,098). Patients Who Were Mandated to Treatment

9 Page 9 of 17 Patients were asked to indicate on the IIF if they were ordered to attend their treatment program by the court or a criminal justice officer. A total of 200 men reported that they had been mandated to receive substance abuse treatment and were coded as 1. Data-Analytic Plan Two domains of outcome variables were examined in the analyses. Substance use was measured by alcohol consumption, absence of an alcohol dependence syndrome, no problems from substance use, remission, and abstinence. Psychosocial outcomes were measured by the absence of clinically significant levels of BSI depression and anxiety, absence of any arrests, employment, and residential status. Paired t tests and McNemar's test for categorical data ( Tabachnick & Fidell, 1989 ) were used to determine significant changes from intake to follow-up for patients within each of the three treatment types. Percent improved (e.g., the proportion patients who were not in remission at intake who were in remission at the follow-up) and deteriorated (e.g., the proportion patients who were in remission at intake who were not in remission at the follow-up) at follow-up are presented as indices of treatment effects. To evaluate the main effects of program type, we used analyses of covariance (ANCOVAs) for continuous and hierarchical logistic regression for dichotomous outcomes. For the latter, program types were dummy coded. The model chi-square improvement after entering program variables was used to determine overall group differences in predicting patient outcomes, and the partial regression coefficients were used to determine between group differences. A Bonferroni correction was used to control for experimentwise Type I error by setting alpha at p <.005 for all analyses. Power was estimated for the main measures (i.e., alcohol consumption, remission) for the primary set of analyses based on Cohen (1987) and Hsieh (1989) ; sample size was sufficient to detect a medium effect at 99% power for both ANCOVA and logistic regression. Odds ratios are presented as indices of the magnitude of the relationship between treatment type and outcomes for significant results ( Hosmer & Lemeshow, 1989 ). The odds ratio estimates the change in the odds of achieving an outcome (e.g., abstinence) based on one treatment type in comparison with another (e.g., 12-step relative to C-B) while controlling for covariates. For analyses using patient subgroups, we used one-stage planned comparisons using ANCOVA and logistic regression. Patient Improvement Results Table 2, Table 3, and Table 4 present data on patient improvement. Patients in all three program types showed significant improvement from intake to follow-up on all 11 outcome variables. Across the programs, patients reported significant decreases in alcohol consumption, fewer met criteria for alcohol dependence, and a greater number had no problems from substance at the 1-year follow-up. The proportion of patients who met criteria for remission and abstinence increased from intake to follow-up. Compared with intake, fewer participants were clinically depressed or anxious on the BSI, had legal problems, were unemployed, or were homeless or in jail at the 1-year follow-up. These results appear to be clinically significant as percent improvement was substantial across the three treatment types (see Tables 2-4).

10 Page 10 of 17 Main Effects of 12-Step, Mixed 12-Step/C-B, and C-B Programs Covariates. Differences in patient pretreatment characteristics may occur when patients are not randomly assigned to treatment. Hence, an array of participants pretreatment characteristics was examined to determine whether they differed across the three program types. Our procedure for covariate selection was the following: (a) variables that most strongly differentiated the three groups were identified, (b) intercorrelations among these variables were examined, and (c) among those highly associated, one variable was chosen. On the basis of this strategy, two demographic characteristics (African American ethnicity and education), a motivational variable (precontemplation stage of change), and several indices of alcohol and drug disorder severity (the presence of any inpatient substance abuse treatment/detoxification in the past 2 years, participating in outpatient substance abuse treatment in the past 2 years, alcohol consumption, any heroin injection in the past 3 months), as well as months from discharge to follow-up (i.e., risk period for relapse) were selected. Finally, we included the intake value of the outcome measure to adjust for intake functioning on the selected outcome. More detailed description of group differences on selected covariates is presented in Table 5. Intake values of the outcome variables were examined among patients in the three treatment types. Before treatment, mixed program participants consumed more alcohol than the other two groups, F (2, 3015) = 12.71, p <.001. A greater proportion of C-B program patients had no problems from substance use than both 12-step and mixed patients, &khgr; 2 (2, N = 3017) = 13.06, p <.001. A greater proportion of mixed program participants had not been arrested in the year before intake as compared with 12-Step and C-B program participants, &khgr; 2 (2, N = 3018) = 30.54, p <.001. Groups did not differ on rates of remission, abstinence, depression, anxiety, or residential and employment status. Main effects of treatment type. At the 1-year follow-up adjusted for covariates, patients from 12-step programs were more likely to be abstinent than patients from C-B programs, and patients from both 12-step and C-B programs were more likely to be employed than patients from mixed programs. The estimated odds of being abstinent were 1.54 times (95% confidence interval [CI] ) greater for 12-step than for C-B patients at the 1-year follow-up. In addition, the estimated odds of being employed were 1.42 times greater (95% CI, ) for 12-step patients and 1.53 times (95% CI: ) greater for C-B patients than for mixed patients at 1 year. Patients from 12-step, mixed 12-step/C-B, and C-B programs did not differ on any other substance use outcomes, BSI depression and anxiety, or legal and residential status after we adjusted for covariates at follow-up (see Table 6 ). Main Effects of Treatment in Specific Treatment Subgroups and Aftercare Main effects of the "purest" 12-step and C-B treatment programs. To provide a more rigorous test of the comparative effectiveness of 12-step and C-B treatment, we identified the four (two 12-step and two C-B) purer programs (i.e., programs in which treatment goals and activities adhered most strongly to their identified philosophy and hours spent in activities related to the other treatment orientation was 5% or less of treatment time based on interviews with the program directors and the DAPTI and SUSS program staff data) and reanalyzed their patients scores on the 11 covariate-adjusted outcome variables. There were 422 patients in the two 12-step programs and 517 patients in the two C-B programs. Patients in these purest 12-step and C-B program participants did not differ significantly on any outcomes. Nonetheless, the rates of abstinence were

11 Page 11 of 17 the same as in the complete sample: 25% of 12-step patients and 18% of C-B patients who were in the purest programs were abstinent at follow-up. Presumably, we had less power in this smaller subsample and hence, did not detect differences between the treatment types. Main effects of treatment among patients who completed their programs. To identify treatment differences, it may be necessary to examine only patients who received a "full dose" of their respective treatment. Hence, analyses examining the main effects of treatment type were performed on the subset of patients who received the "full dose" of 12-step, C-B, and mixed treatment. Results were the same as in the complete sample. Main Effects of Treatment in Specific Patient Subgroups Patients with only substance-related and those with concomitant psychiatric diagnoses. The relative effectiveness of 12-step, mixed, and C-B programs was examined in patients with only substance-related disorders. At the 1-year follow-up, adjusted for covariates, patients who had only substance-related diagnoses did not differ on substance use or psychosocial outcomes relative to treatment in 12-step, mixed, or C-B programs. Patients with concomitant psychiatric diagnoses in the three treatment types also did not differ on 1-year covariate-adjusted substance use or psychosocial outcomes. Patients who were coerced into treatment by the legal system. No differences emerged on outcomes by program type for the 200 patients who were mandated to treatment by a court or a criminal justice officer. To note, the results for the 2,817 patients who were not mandated to treatment were similar to the original analyses. Discussion This study examined patient improvement and the main effects of 12-step, mixed 12-step/C-B, and C-B treatment programs on an array of outcome variables at a follow-up approximately 1 year after treatment discharge. Although patients in 12-step programs were somewhat more likely to be abstinent and although patients in 12-step and C-B programs had somewhat better rates of employment at 1 year, 12-step, mixed 12-step/C-B, and C-B programs were otherwise equally effective in reducing patient's substance use, psychological symptoms, and increasing the proportion of patients who avoided legal problems and who were not incarcerated or homeless. Similar findings were obtained in patients who completed their treatment programs and no differences were found on outcomes in patients who were in the purest 12-step and C-B treatment programs. Finally, patients with only substance-related disorders and those with psychiatric diagnoses, and patients who were mandated to treatment were examined separately; 1-year outcomes for each of these patient groups did not differ by type of treatment received. Patient Improvement Across the three program types, patients reported significant reductions in substance use and symptoms at the 1-year follow-up, including substance-related problems. More patients were in "remission," which required abstinence or nonproblem use of alcohol and no illicit drug use. Patients reported more abstinence from use of alcohol and illicit drugs, less depression and anxiety, and fewer had legal problems, and more were employed at the 1-year follow-up. Also, fewer patients were in

12 Page 12 of 17 jail or homeless. However, it is important to note that many patients continued to struggle with substance use and associated problems at the 1-year follow-up (only 25% were in remission and over half were unemployed). Programs caring for these patients need to plan for high rates of recidivism and pervasive life problems such as unemployment. Also significant are the high rates of clinical depression and anxiety as measured by the BSI at the 1-year follow-up. Patients in these programs are likely to need periodic care over an extended period that addresses substance use, psychological, residential, and vocational concerns. In light of the severity of this patient population, the respective gains made after treatment are more impressive. Main Effects of 12-Step, Mixed 12-Step/C-B, and C-B Treatment At the 1-year follow-up, the majority of findings did not favor one form of treatment over another. Only two significant findings emerged on outcomes when patients in the three treatments were compared. Importantly, when patients receiving the full dose of treatment in the three treatment groups were examined, patient outcomes remained similar after 12-step, mixed, or C-B treatment. Furthermore, when the most exemplary 12-step and C-B programs were examined, no differences emerged on substance use and psychosocial outcomes. Taken together, the evidence from this naturalistic study and the Project MATCH Research Group (1996) multisite clinical trial of 12-step and C-B treatments suggests that 12-step and C-B models of treatment may be equally effective for substance abuse patients. These findings may be surprising given the seemingly disparate models underlying the 12-step and C- B approaches. However, in a recent review, McCrady (1994) also identified several common treatment elements of 12-step and behavior therapy. For example, both models emphasize initial behavior change, development of activities incompatible with drinking and drug use, and identification and change of dysfunctional cognitions. These similar goals, although gained through different models of change, may explain the comparable outcomes among participants in the three sets of programs. Indeed, in examining changes in process (proximal outcome) variables from intake to discharge for these patients, Finney, Noyes, Coutts, and Moos (1996) found that 12-step and C-B patients similarly improved on what were conceptualized as general proximal outcomes of substance abuse treatment (e.g., self-efficacy, reinforcement and outcome expectancies, coping skills). In addition, it is possible that treatments with sharply contrasting theories and methods may nonetheless similarly impact on posttreatment functioning (e.g., Elkin et al., 1989 ; Imber et al., 1990 ). At the 1-year follow-up, 25% of the patients treated in 12-step programs were abstinent compared with 18% of the patients treated in C-B programs. This difference probably reflects the different goals of 12-step and C-B treatment. According to 12-step philosophy and methods, abstinence is the key to recovery. In contrast, C-B theory and method allow individuals to set their own goals, which may range from controlled drinking to abstinence ( Monahan & Finney, 1996 ). The finding that patients treated in 12-step and C-B programs did not differ on rates of remission supports this explanation. Consistent with our findings, Project MATCH also found a slight advantage for outpatients in 12-step over C-B treatment on a measure of abstinence at the follow-up. One caution in interpreting our finding was that 12-step patients were less likely than C-B patients to complete the 1-year follow-up, which may bias our findings toward favoring 12-step patient outcomes ( Monahan & Finney, 1996 ). Patients in 12-step and C-B programs were more likely to be employed than mixed program participants (adjusted means of 41% and 40%, respectively, vs. 34%) at follow-up. Programs strongly emphasizing only one approach, rather than a mixture of treatment modalities may be better at implementing these goals and helping their patients. In a study of patient outcomes after drug

13 Page 13 of 17 psychotherapy or counseling, Luborsky and colleagues found that purity of therapy, or the degree to which the therapist adhered to her or his intended treatment orientation, predicted better substance use and psychosocial outcomes, including employment status ( Luborsky, McLellan, Woody, O'Brien, & Auerbach, 1985 ). However, it should be noted that the magnitude of the relationship between treatment types and employment status was modest. Main Effects of Treatment in Specific Patient Diagnostic Subgroups Because 12-step philosophy emphasizes primary treatment of substance abuse, it was proposed that these treatments may be differentially effective relative to patient diagnosis; those with only substance-related diagnoses were examined separately from patients with a dual diagnosis. These hypotheses were not supported in this sample, potentially reflecting the treatment setting (i.e., inpatient), and the administration of the 12-step intervention by professionals. Inpatient facilities may have greater access to and support from psychology, psychiatry, and general medical staff. Hence, staff and patients in inpatient 12-step programs may be more accepting of a simultaneous focus on substance abuse and nonsubstance-related psychological symptoms, and the use of psychotropic medications for psychiatric disorders. Our initial hypotheses may be more relevant to outpatientbased therapy (cf. Project MATCH Research Group, 1996 ) or mutual help 12-step programs, such as Alcoholics Anonymous. On a practical level, our findings do not support the assignment of patients to 12-step or C-B VA inpatient treatment based on the presence or absence of a concomitant psychiatric disorder. Nonvoluntary attendance has been proposed to change the nature of 12-step groups (see Humphreys & Rappaport, 1994 ) and, hence, may lessen their effectiveness. In this study, patients who were mandated to treatment were separately examined to evaluate any negative impact that coercion may have on patient outcomes after 12-step relative to C-B treatment. Patients who were mandated to treatment did not differ on 1-year outcomes by treatment type. This finding suggests that courtreferred patients may similarly benefit from professional 12-step and C-B treatment. One limitation to our study is the smaller size of the court-referred patient group may have restricted our ability to identify differential treatment effects. Power to detect a medium effect size was only 65% at the p <.005 level for this subgroup. Nonetheless, even when alpha was increased to p <.05, patients who had been treated in 12-step programs did not differ from patients in either C-B or mixed programs on 1-year outcomes. Conclusion Limitations of the present evaluation include its unknown generalizability to nonveterans and women, and to outpatient or treatments of shorter or longer duration. Future studies need to focus on treatment outcome for women veterans who report substance abuse problems. Another issue that affects the interpretability of the results is nonrandom assignment to treatment; we used statistical controls to address preexisting patient differences that may have affected results. However, our conclusions are strengthened and complemented by two studies using randomized trials to investigate the main effects of 12-step and C-B treatments, both of which had findings generally consistent with ours ( Project MATCH Research Group, 1996 ; Wells et al., 1994 ). Patient-treatment matching hypotheses were not examined beyond exploring global diagnostic categories. In future analyses, we plan to examine the data to identify the most effective programs for different types of patients. Unfortunately, logistical difficulties associated with this sample of substance abuse patients (e.g., frequent moves, lack of consistent social networks) and limited resources prevented rigorous

14 Page 14 of 17 collection of corroborating data for self-reports. Future studies should pursue both biological and informant corroboration of self-reports of substance use and other sources of validation for self-report of other outcomes (e.g., informant reports, official judicial reports of legal status, direct confirmation of employment status from the workplace; for a review of these issues, see Carroll, 1995 ). We were unable to collect objective data (e.g., videotaped sessions of treatment groups) to validate information from the program directors surveys. However, we did obtain staff survey and treatment program site visit data as corroborating information which support the findings from the program directors surveys. Type of aftercare during the 1-year follow-up may have affected the impact of the three treatment modalities on 1-year outcomes. Unfortunately, we do not have information on the treatment philosophy of outpatient mental health clinic visits after the index inpatient stay and cannot directly address this issue with our data. Future reports will examine the impact of aftercare (i.e., outpatient treatment and 12-step involvement) on patient 1-year outcomes. Another major limitation of this study was the lack of a no-treatment control group. Hence, the possibility exists that these three treatment programs produce patient outcomes similar to those that naturally occur with no treatment. However, a series of studies by Timko and colleagues suggest that treatment is superior to no treatment for alcoholic individuals. Among previously untreated alcoholic individuals, those who received treatment had better drinking outcomes than those who did not receive treatment at 1- and 3-year follow-ups ( Timko, Finney, Moos, & Moos, 1995 ; Timko, Moos, Finney, & Moos, 1994 ). The possibility remains that 12-step and C-B treatments are no more effective than a nonspecific substance abuse treatment. Our main finding was that patients in 12-step and C-B treatment for substance abuse generally do not differ on outcomes 1 year postdischarge. This lack of difference is consistent with the broader literature on comparative psychotherapy outcome, which generally finds no differential effectiveness among treatments for mental health problems (e.g., Luborsky, Singer, & Luborsky, 1975 ; Smith, Glass, & Miller, 1980 ). That patients in 12-step fared as well as those in C-B programs is important new evidence-suggesting 12-step is an effective treatment alternative and merits further scientific study. References American Psychiatric Association (1987). Diagnostic and statistical manual of mental disorders (3rd ed., rev.). Washington, DC: Author. Babor,T. F., Stephens,R. S. & Marlatt,G. A. (1987). Verbal report methods in clinical research on alcoholism: Response bias and its minimization. Journal of Studies on Alcohol, 48, Buckner,J. C. & Mandell,W. (1990). Risk factors for depressive symptomatology in a drug using population. American Journal of Public Health, 80, Buxton,M. E., Smith,D. E. & Seymour,R. B. (1987). Spirituality and other points of resistance to the 12-step recovery process. Special issue: Professional treatment and the 12-step process. Journal of Psychoactive Drugs, 21, Carroll,K. M. (1995). Methodological issues and problems in the assessment of substance abuse. Psychological Assessment, 7, Cohen,J. (1987). Statistical power for the behavioral sciences (rev.ed.). Hillsdale, NJ: Erlbaum. Cooper,A. M., Sobell,M., Maisto,S. & Sobell,L. (1980). Criterion intervals for pretreatment drinking

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