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. Author manuscript; available in PMC: 2007 Sep 27.
Published in final edited form as: Psychiatr Serv. 2004 Aug;55(8):913–922. doi: 10.1176/appi.ps.55.8.913

The Development and Implementation of Case Management for Substance Use Disorders in North America and Europe

Wouter Vanderplasschen 1, Richard C Rapp 2, Judith R Wolf 3, Eric Broekaert 4
PMCID: PMC1994722  NIHMSID: NIHMS29641  PMID: 15292541

Abstract

Because of the multifaceted, chronic, and relapsing nature of substance use disorders, case management has been adapted to work with persons who have these disorders. Deliberate implementation has been identified as a powerful determinant of successful case management. This article focuses on six key questions about implementation of case management services on the basis of a comparison of experiences from the United States, the Netherlands, and Belgium. It was found that case management has been applied in various populations with substance use disorders, and distinct models have been associated with positive effects, such as increased treatment participation and retention, greater use of services, and beneficial drug-related outcomes. Program fidelity, robust implementation, extensive training and supervision, administrative support, a team approach, integration in a comprehensive network of services, and minimal continuity have all been linked to successful implementation.


Case management is regarded as one of the most important innovations in mental health and community care of the past decades (1). It is a client-centered strategy to improve coordination and continuity of care, especially for persons who have multiple needs (2). Regardless of the controversy of whether, in what form, and to what extent case management is effective, this intervention has a long history for the treatment of various populations of persons with mental illness in the United States, Australia, and Canada and in several European countries (3-7).

Since the 1980s, case management has been adapted to work with persons with substance use disorders (8-10), which were increasingly becoming recognized as multifaceted, chronic, and relapsing disorders that required a comprehensive and continuous approach (11,12). Although modeled after mental health examples, case management for persons with substance use disorders was developed separately, illustrating the originally strong distinction between the substance abuse and mental health treatment sectors in several countries (13-15). Lightfoot and colleagues (16) were the first to show that case management could reduce attrition from treatment and improve both psychosocial and drug and alcohol outcomes among persons with substance use disorders.

Since the 1990s, hundreds of programs in Canada and the United States and some in Europe—for example, Germany, the Netherlands, and Belgium—have implemented case management (14,17), expecting a positive impact on treatment participation and retention, coordination of service delivery, and drug-related outcomes. The increased need for case management has been attributed to the growing complexity of individuals' problems and systems of care (11,18).

Despite its widespread application and popularity, case management is not unanimously defined, and its practice varies from place to place because of diverging objectives, distinct target populations, program and system variables, and other immediate local concerns (19-21). One of the first definitions described case management as “that part of substance abuse treatment that provides ongoing supportive care to clients and facilitates linking with appropriate helping resources in the community” (22). A more accurate way of characterizing case management is to postulate its basic functions: assessment, planning, linking, monitoring, and advocacy (14). Furthermore, some broad principles are true of almost every application of case management: community based, client driven, pragmatic, flexible, anticipatory, culturally sensitive, and offering a single point of contact.

Given that deliberate conceptualization and implementation have been identified as powerful determinants of successful practice and outcomes (6,21,23-25), we conducted a comparative review of available literature focusing on issues concerning the implementation of case management for substance use disorders. The goal of the review was to provide insight into some of the do's and don't's when developing this intervention on the basis of experiences in North America (the United States) and Europe (the Netherlands and Belgium)—countries that loosely represent three points on a continuum.

This comparison started from exploring similarities and dissimilarities between these selected countries during a workshop on case management at the Third International Symposium on Substance Abuse Treatment and Special Target Groups, held March 5 and 6, 2001, in Blankenberge, Belgium (26). Discussions between researchers from these countries led to the joint identification of six key questions, which are elaborated on in this article on the basis of available literature and empirical evidence.

Information was obtained through repeated searches in MEDLINE, PsycLIT, PubMed, and the Web of Science for articles published since the 1990s, using the terms “substance abuse–addiction–substance use disorders,” “case management,” and “development–implementation.”

Key questions

Which problems are addressed with case management, and what are its objectives and target group?

The observation that many persons with substance use disorders have significant problems in addition to abusing substances has been the main impetus for using case management as an enhancement and supplement to substance abuse treatment (27-31). In the United States, the paucity and selective accessibility of available services, shortcomings in the overall quality of service delivery (accountability, continuity, comprehensiveness, coordination, effectiveness, and efficiency), and cost containment were further incentives for implementing case management (14, 18,19,32). The implementation of case management in the Netherlands was not driven merely by economic concerns but rather by the poor quality of life of many chronic addicts and the nuisance they cause in city centers (31). In Belgium, the chronic and complex problems of many substance abusers and the lack of coordination and continuity of care were the main reasons for introducing case management (30).

Unlike in the United States, case management has not been applied as widely among substance abusers in Europe because of better availability and accessibility of services, less stress on cost containment, and conflicting outcomes about the effectiveness of case management for persons with mental illness, among other reasons. However, recent reforms in substance abuse treatment—for example, in the Netherlands, Germany, and Belgium—have shifted the focus toward accessibility, continuity, cost-effectiveness, and efficiency and stimulated interest in case management (15,33,34). Since 1995, more than 50 projects have been developed in the Netherlands that make use of case management, whereas the number of case management projects for this population in Belgium is limited to five to ten (30,31).

In the United States, case management has been implemented successfully for enhancing treatment participation and retention among substance abusers in general (35-38) and for populations with multiple needs that experience specific barriers in obtaining or keeping in touch with services, such as pregnant women, mothers, adolescents, persons who are chronically publicly inebriated, persons with dual diagnoses, and persons with HIV infection (11,39-44). Most of these programs intend to promote abstinence, whereas case management programs in Europe apply a harm-reduction perspective. In the Netherlands, the implementation of case management has been directed mainly at severely addicted persons, such as street prostitutes, mothers of young children, homeless persons, and persons with dual diagnoses, who are often served inadequately or not at all by existing services. According to program providers, case management has contributed substantially to the stabilization of these persons' situation (45). In Belgium, case management has mainly been reserved for substance abusers with multiple and chronic problems, resulting in improved drug-related outcomes and better coordination of the delivery of services (46).

Target populations may also include persons with substance use disorders who are involved in the criminal justice system, and these interventions have been associated with reduced drug use and recidivism and with increased service use (47-49). However, uncertainty remains about the differential effect of coercion in case management (50,51). This intervention has further been used to address “the most problematic clients,” an approach that has been associated with adverse outcomes in the field of mental health care (6), but various studies among substance abusers have shown cost-effectiveness and beneficial outcomes (16,40,52-56). Nevertheless, several authors have reported practical problems—for example, the difficulty of long-term planning, increased risk of burnout among case managers, and clients' becoming totally dependent on their case manager (21,46,53,57).

An overview of recently published (1997 to 2003) peer-reviewed studies of case management that have included at least 100 substance abusers revealed that case management has been relatively successful for achieving several of the postulated goals in the United States, whereas similar outcome studies are still forthcoming in Europe (Table 1). Several controlled studies have shown significant improvements in treatment access, participation, and retention or service use among clients who have received case management services (36,37,58-65), whereas evidence on the effects on drug-related outcomes is still conflicting. Generally, small to moderate improvements have been demonstrated among clients who received case management services (58,62,64, 66,67), but these effects sometimes tended to decline over time (after nine to 12 months) (38,59) or did not differ significantly from those of similar control interventions, such as behavioral skills training and other models of case management (25,44,60). Finally, various uncontrolled studies have shown significantly improved outcomes compared with baseline assessments (34,35,46,68). However, in the absence of a control condition, such effects may have wrongly been attributed to case management.

Table 1.

Overview of main results of recently published studies (1997 to 2003) in peer-reviewed journals about case management (CM) for persons with substance use disorders (N>100)

Results
Study Target
population
Type of
intervention
Access, participation,
and retention
Service use Drug-related
outcomes
Conrad et al. (59) 1998, Hines, Illinois, N=358 Homeless
addicted male
veterans
Case managed
residential care
versus 21-day
hospital program
with
referral to
community
services
CM group stayed
about 3 months
longer in residential
treatment.
Both groups used
substantial amounts
of services.
Both groups improved significantly
over time (24
months); CM group had significantly
better medical,
alcohol, employment, and
housing outcomes after 6
and 9 months, but these
differerences disappeared
after 12 and 24 months.
Cox et al. (52) 1998, King County, Seattle, N=298 Homeless
chronic
public
inebriates
Intensive CM
versus standard
treatment
CM group received
a significantly higher
number of substance
abuse treatment and
other services.
Both groups improved over
time (18 months), but CM
group had significantly fewer
days of drinking (11.3
versus 15.4), more nights
spent in own place (25.4
versus 21.7), and increased
total income from public
sources ($358 versus $269).
Drake et al. (66), 1998, New Hampshire, N=223 Persons with
dual diagnoses
Assertive
community
treatment (ACT)
versus standard
case management
No difference in
number of days
hospitalized
ACT group improved significantly
more on some measure
of substance dependence
and quality of life,
but the groups had equally
significant improvement in
the number of days living
in the community (171.4
versus 167.7), remission (43
versus 35 percent), and psychiatric
symptoms after 36
months.
Evenson et al. (68), 1998, St. Louis, Missouri, N=280 Substance
abusers in a
comprehensive
treatment and
rehabilitation
program
Community
program,
including
intensive case
management
Association between
longer stay and more
favorable outcomes
(ns)
High degree of
satisfaction with
services received
(32 percent satisfied
and 62 percent
very satisfied)
Significantly improved
functioning on 11 domains,
such as global functioning
(17-point drop in GAF
score), drug use, productivity,
legal problems, and
distress, and 30 percent
more were living indepenpendently
compared with
baseline.
Godley et al. (62), 2002, Illinois, N=114 Adolescent
substance
abusers in
short-term
residential
treatment
Assertive continuing
care
including case
management
versus usual
continuing care
No differences in
length of stay and
treatment completion
status
CM group was
significantly more
likely to initiate
and receive
continuing care
services (92
versus 59 percent).
CM group was significantly
more likely to be abstinent
from marijuana (52
versus 31 percent) and had
fewer days of alcohol use
(4.5 versus 8.1) 3 months
after discharge.
Huber et al. (65), 2003, Johnson County, Iowa, N=598 Substance
users seeking
treatment in
a rural area
Strengths-based
case management
(3 conditions:
inside facility,
at social service
agency, and telecommunication)
versus a control
condition
Persons who participated
in CM were less
likely to have legal
problems (30 versus 43
percent) and fewer
days of family problems
(3.1 versus 4.6) but
were more likely to
have chronic medical
status (32 versus 22
percent).
Clients in the
telecommunication
condition received
greater breadth and
frequency of services,
but the duration
was longer
in the non-CM
condition.
CM dosage was significantly
related to more severe
legal and family problems
after 12 months.
McLellan et al. (37), 1999, Philadelphia, N=537 Substance
abusers in
outpatient
treatment
Clinical CM
versus standard
outpatient
treatment
CM group received
significantly more alcohol
(87 versus 68
percent), medical (58
versus 36 percent),
employment (75 versus
39 percent), and
legal services (39
versus 27 percent).
Both groups improved significantly
in most life areas
after 6 months, but the CM
group showed significantly
more improvement in alcohol,
drug, psychiatric,
employment, and medical
status.
Mejta et al. (56), 1997, Chicago, N=316 Intravenous
drug users
seeking treatment
through
a centralized
intake facility
Generalist CM
versus control
condition with
limited referral
information
CM group was significantly
more likely to
obtain treatment (98
versus 57 percent), to
enter treatment more
rapidly (after 17 versus
188 days), and to stay
in treatment (27 versus
14 months).
CM group had better treatment
outcomes, including
reduced drug and alochol
use.
Rapp et al. (60), 1998, Dayton, Ohio, N=444 Veterans with
substance use
problems seeking
treatment
Strengths-
based CM
versus standard
primary and
aftercare
treatment
Significant positive relation
between length
of post-primary treatment
contact and case
management (r=.408)
CM had no direct impact
on the severity of drug use
after 6 months, but effects
were mediated by treatment
retention.
Saleh et al. (38), 2002, Johnson County, Iowa, N=662 Substance users
seeking
residential
treatment in a
rural area
See Huber et
al. (65)
No differential effectiveness
between groups for reducing
substance abuse. The
“outside” CM group had
significantly more improvement
than the control
group in reduction of drug
abuse at 3 months and psychiatric
problems at 3 and
12 months. The CM group
had significantly greater
improvement than the control
group in legal status at
3 and 6 months and employment
problems at 12
months.
Sarrazin et al. (67), 2001, Johnson County, Iowa, N=494 Substance
users seeking
residential
treatment in a
rural area
See Huber et
al. (65)
CM had a significant impact
on perceptions of family
relations and parental attitudes
after 6 months but
not on perception of partner
abuse. No such effects
were found after 3 and 12
months. All 4 groups experienced
significant improvement
in substance abuse.
Scott et al. (63), 2002, Chicago, N=692 Substance
abusers who
contacted a
centralized
intake facility
Brokerage CM
versus no case
management
CM group significantly
more likely to show up
for treatment (79 versus
72 percent). No
differences in length
of stay.
CM clients significantly
more likely
to be referred to
ancillary services
(9 versus <1 percent).
No differences
in number
of services received.
Shwartz et al. (35), 1997, Boston, N=21,207 Substance
abusers discharged
from
4 types of
treatment
Generalist
CM
CM group stayed 1.6
to 3.6 times longer in
treatment. Significant
correlation between
length of stay and
improved outcomes.
CM group followed
1.7 times more post-
primary treatment.
CM group 25 to 30 percent
less likely to be readmitted
to detoxification, indicating
a reduced relapse rate.
Siegal et al. (36), 1997, Dayton, Ohio, N=313 Veterans with
substance use
problems who
were assigned
to CM
Strengths-based
CM versus
versus standard
primary and
aftercare
treatment
Positive relationship
between treatment
retention and improved
outcomes.
Without CM, another
third of the sample
would have dropped
out after primary
treatment.
Significantly fewer clients
who received CM and aftercare
used cocaine in the
past 6 months (25 versus
33 and 47 percent) and
more persons attended
self-help group sessions in
the past 30 days (82 versus
70 and 48 percent) in the
past 6 months. Significantly
fewer persons from the CM
group were involved in illegal
activities during the
past 30 days (9 versus 18
and 24 percent), and more
had steady employment
after 6 months (69 versus
59 and 54 percent). Clients
who dropped out of CM
and usual aftercare had the
lowest levels of functioning.
Siegal et al. (64), 2002, Dayton, Ohio, N=453 Veterans with
substance use
problems
Strengths-based
management
versus standard
primary and
aftercare
treatment
CM was a significant
predictor of length of
posttreatment aftercare
(β=.425)
Clients who reported new
arrests had significantly fewer
weeks of aftercare services
(6.2 versus 8.9).
Length of aftercare participation
was significantly associated
with employment
(β=−.089) and readiness for
treatment (β=.092). Longer
stay in aftercare was related
to less severe legal problems
at follow-up (β=.112).
Sorenson et al. (44), 2003, San Francisco, N=190 Substance
abusers with
HIV or AIDS
Brokerage
versus intensive
case management
No significant
differences in
service use
Equal significant decrease in
problems after 6 months in
both groups, but no significant
pattern of change after
12 and 18 months. Significantly
greater sexual risk index
in brokerage CM group.
Vaughan-Sarrazin et al. (61), 2000, Johnson County, Iowa, N=287 Substance
users seeking
residential
treatment in
a rural area
See Huber et al. (65) Significantly more CM
clients used treatment
services during the first
two trimesters (likelihood
ratio=3.79). In
particular, use of medical
and substance abuse
services increased, not
that of mental health services.
Face-to-face CM
led to significantly increased
service use
(LR=7.94). Use of treat-
services declined steadily
over the 12-month
period.

What is the position of case management in the system of services, and how can cooperation and coordination between services be enhanced?

Several authors have argued that the success of case management depends largely on its integration within a comprehensive network of services (8,21,69-71). Case management risks being just one more fragmented piece of the system of services if it is not exquisitely sensitive to potential system-related barriers, such as waiting lists, inconsistent diagnoses, opposing views, and lack of housing and transportation (72).

McLellan and colleagues (37) found no effects of case management 12 months after implementation but did find effects after 26 months. They concluded that there was a strong influence of various system variables—for example, program fidelity and availability and accessibility of services—and recommended extensive training and supervision to foster collaboration and precontracting of services to ascertain their availability. Access to treatment can be markedly improved when case managers have funds with which to pay for treatment (58). In addition, formal agreements and protocols are needed concerning the tasks, responsibilities, and authorities of case managers and other service providers involved; the use of common assessment and planning tools; and exchange and management of client information (13,14,21,57,73).

Case management can be implemented as a modality provided by or attached to a specific organization, such as a hospital or a detoxification center, or as a specific service jointly organized by several providers to link clients to these and other services. The former program structure has been widely applied in the United States for enhancing participation and retention and reducing relapse, whereas the latter is frequently used in Belgium and the Netherlands to address populations at risk of falling through the cracks of the system.

Vaughan-Sarrazin and colleagues (61) studied the differential impact of programs' locations and compared the effectiveness of three types of case management with a control condition. The variant that involved case managers housed inside the facility was associated with significantly greater service use compared with the other conditions, which suggests that the accessibility and availability of case management programs mediate the success of these programs.

What model of case management should be used, and which are crucial aspects of effective case management?

Although most practical examples only vaguely resemble the pure version of a case management model, four models of case management are usually distinguished for working with substance use disorders: the brokerage-generalist model, assertive community treat-ment–intensive case management, the strengths-based model, and clinical case management (14,19). Model selection should be dictated by what services are already available, the objectives and target population, and any available empirical evidence.

Assertive community treatment, and especially intensive case management, with its focus on a comprehensive (team) approach and the provision of assertive outreach and direct counseling services, has been used in the United States for reintegrating incarcerated offenders, among other populations (24,47,49). A randomized study of 135 parolees, half of whom received case management services, showed little differential effect on drug use, but some improvement was found in relation to risk behavior and recidivism (24).

Random assignment to intensive case management compared with two other interventions was associated with a decline in drug use and criminal involvement and an increase in treatment participation among almost 1,400 arrestees (49). In addition, intensive case management has been applied successfully in other populations with complex and severe problems—for example, homeless persons and persons with dual diagnoses (40,42,52,53,66,68). Intensive case management is the predominant model in Belgium and the Netherlands and has been associated with the delivery of more comprehensive and individualized services and improved outcomes (31,46).

Two large studies in Dayton, Ohio, and in Iowa, sponsored by the National Institute on Drug Abuse, have applied strengths-based case management among persons with substance abuse who are entering initial treatment (Table 1). The Ohio study found evidence for improved employment functioning and enhanced treatment retention, which, in turn, was associated with a positive effect on outcomes concerning drug use and criminal involvement (36,60,64,74,75). According to clients, retention was promoted by the client-driven nature of goal setting and was facilitated by case managers' assistance in teaching clients how to set goals (76). The Iowa study showed an impact of case management on the use of medical and substance abuse services and moderate, but fading, effects on legal, employment, family, and psychiatric problems (32,38,61,65,67).

Brokerage models and other brief approaches to case management have usually not demonstrated any discernable benefits of case management compared with control groups who did not receive case management services (77,78). However, recent studies have shown a positive impact of case management on service use and access to treatment (66) and equal effectiveness compared with intensive case management (44). Generalist or standard case management has been associated with significant positive effects on treatment participation and retention and relapse (35,58). Clinical case management, which combines resource acquisition and clinical activities, has rarely been applied among persons with substance use disorders but was successful in at least one study (37). Other authors have stated that combining the role of counselor and case manager is problematic, because it dilutes both aspects of the program (24).

In summary, as opposed to case management for persons with mental illness (3,6,79,80), little information is available about crucial features of distinct models and their effectiveness for specific substance abusing populations.

Which qualifications and skills should case managers have, and what types of support should be provided?

Several authors assume that previous work experience, extensive training, knowledge about the health care and social welfare systems, and communication and interpersonal skills are at least as important as formal qualifications (14,31,34). Only some programs have involved people who have recovered from addictions as case managers (81), but no information is available about the differential impact of case management by professionals or peers. The client–case manager relationship has been identified as crucial for promoting case management participation and related outcomes, and the application of a strengths-based approach can stimulate clients' involvement (34,46,74,76).

Analyses of case management activities and program fidelity have shown large variations among case managers, not only within but also across programs (13,14,25,35,44,68). Poor program fidelity and nonrobust implementation of case management have been associated with worse outcomes, but fidelity and implementation can be optimized by extensive initial training, regular supervision, administrative support, application of protocols and manuals, treatment planning, and a team approach (13,25,37).

Variety across programs has resulted in attempts to standardize and guide case management in the United States. The National Association of Alcoholism and Drug Abuse Counselors identified case management as one of eight counseling skills (82), and the commonly cited case management functions have been incorporated into the referral and service coordination practice dimensions of the addiction counseling competencies (83). In the Netherlands, a Delphi study was organized to reach a broad consensus on the core features of case management, resulting in a manual that will serve as a touchstone for the future development, implementation, and evaluation of case management (31,84). The Delphi method comprises a series of questionnaires sent to a preselected group of experts—for example, clients, case managers, and program directors—who respond to the problems posed individually and who are able to refine their views as the group's work progresses (85). It is believed that the group will converge toward the best response through this consensus process, based on structuring of the information flow and feedback to the participants.

Case managers' caseloads vary but usually do not exceed 15 to 20 clients for a case manager who is providing intensive contacts to substance abusers who have multiple and complex problems (13,21,34,41,52). A team approach helps to deal with large and difficult caseloads but also to extend availability and guarantee case managers' safety (34,86). Most researchers have found little effect of the intensity of mental health case management (6,35,44), whereas others have related high “dosages” of case management with either improved or adverse outcomes (34,68).

How should case management projects best be financed, and how can their continuity be guaranteed?

The burgeoning interest in managed care financing structures resulted in an explosive growth of case management initiatives in the United States during the 1990s (32). Most programs have been set up as experiments, but, despite positive results, only some have been integrated into the service system on a long-term basis. On the other hand, case management programs in the Netherlands became part of the system of services shortly after implementation and without many indications of effectiveness (31). Both observations illustrate that continued funding might be predicted on the basis of issues that have little to do with success or failure of the intervention itself.

Developing projects should be given sufficient time—three to five years—to realize their objectives, given that it has been shown that it may take up to two years before case management generates the intended outcomes (37). Alternative or flexible forms of reimbursement need to be negotiated with insurance companies, because case managers' activities often represent departures from traditional interventions in substance abuse treatment (87). In addition, a budget for occasional client expenses—for example, child care, clothing, and public transportation—can facilitate case management (37,43,57). Ultimately, continued funding should be based on a thorough evaluation of the program's postulated goals.

Which standards should be used to evaluate case management?

Effectiveness needs to be evaluated according to scientific standards, but requirements from commissioning and subsidizing authorities should also be taken into account (14). Evaluation should start from an accurate representation of what the intervention entails (23). Without this knowledge, it is only possible to vaguely search for outcomes that might be more or less attributable to case management. Besides outcome indicators, process data should be collected that describe the degree to which the planned intervention is actually delivered, the impact of other factors on the intervention, and the specific outcomes that can be attributed to case management (14,47).

Researchers have identified several potential confounding factors—for example, individual case managers' personalities, client characteristics, motivation, legal status, and treatment participation and retention—that affect the direct impact of case management on clients' functioning (25,36,52,68,60,64,88,89). Contextual differences cause further methodologic problems in the evaluation of case management. To extend current knowledge about the effectiveness of case management for persons with substance use disorders, more randomized controlled studies with large samples are needed, especially in Europe. Also, a longitudinal scope and qualitative research that focuses on specific aspects of case management and the role of mediating variables could provide further insights into the factors that make case management work.

Conclusions

In both the United States and Europe, case management is regarded as an important supplement to traditional substance abuse services, as it provides an innovative approach—client centered, comprehensive, and community based—and contributes to improved access, participation, retention, service use, and client outcomes. Compared with case management for persons with mental illness, case management for persons with substance use disorders has fairly little evidence available of effectiveness.

Contextual differences, specific target populations, diverging objectives, less tradition of community care, few randomized and controlled trials, and unrealistic expectations about the effectiveness of case management in this population may account for this lack of evidence. Especially in Europe, more randomized controlled trials that include sufficiently large samples are needed, as well as qualitative studies, in order to better understand distinct aspects of case management and their impact on client outcomes and system variables.

Case management for substance use disorders is no panacea, but it positively affects the delivery of services and can help to stabilize or improve an individual's complex situation. On the basis of empirical findings from the United States, the Netherlands, and Belgium, several prerequisites for a well-conceptualized implementation of this intervention can be mentioned. Integration of the program in a comprehensive network of services, accessibility and availability, provision of direct services, use of a team approach, application of a strengths-based perspective, intensive training, and regular supervision all contribute to successful implementation and, consequently, to beneficial outcomes.

Still, the variety of case management practices within and across programs remains a major concern. Development of program protocols and manuals and the identification of key features of distinct models can contribute to a more consistent application of this intervention.

Finally, although case management for persons with substance use disorders has evolved somewhat independently, many similarities can be observed with mental health case management. Therefore, further evolutions in this sector should be closely followed, especially for identifying the crucial features of case management. Moreover, a comparison of case management for both populations may reveal unique aspects of each intervention that allow optimization of case management practices among patients with mental illness, persons with substance use disorders, and persons with dual diagnoses.

Acknowledgments

The Third International Symposium on Substance Abuse Treatment and Special Target Groups, held March 3 to 5, 2001, in Blankenberge, Belgium, was financially supported by the Province of East Flanders and the European Federation of Therapeutic Communities.

Contributor Information

Wouter Vanderplasschen, The department of orthopedagogics at Ghent University, H. Dunantlaan 2, B-9000, Ghent, Belgium (e-mail, wouter.vanderplasschen@ugent.be).

Richard C. Rapp, The center for interventions, treatment, and addictions research at Wright State University School of Medicine in Dayton, Ohio.

Judith R. Wolf, Trimbos Institute in Utrecht, the Netherlands, and with the department of social medicine at Catholic University of Nijmegen in Nijmegen, the Netherlands.

Eric Broekaert, The department of orthopedagogics at Ghent University.

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