Journal of Addiction & Addictive Disorders Category: Clinical Type: Commentary

Dual Disorder: Substance Use Disorder in People with Severe Mental Disorders

Fernandez JA1*
1 Centro de Día de la Casa del Mar, Las Palmas de Gran Canaria, Spain

*Corresponding Author(s):
Fernandez JA
Centro De Día De La Casa Del Mar, Las Palmas De Gran Canaria, Spain

Received Date: Dec 30, 2021
Accepted Date: Jan 06, 2022
Published Date: Jan 13, 2022


What is dual disorder? 

History of the concept: In the early 1980s, Pepper and Ryglewicz [1] used the acronym YACP (Young Adult Chronic Patient) to define a new profile of “new chronics” as opposed to the profile of the “old institutionalised chronic”. YACP was a new generation of people with Severe Mental Disorder (SMD): young, between 18 and 35 years old, with different diagnoses, living in their community and using drugs. They were also called “new chronics”, as opposed to the classic “chronic institutionalised” and were characterised by severe social adjustment deficits, poor engagement with health services, frequent aggressive behaviours and being a problem for community mental health services: they do not attend community consultations, drop out of treatment, are frequently admitted to inpatient units and increase the burden on their families. Pepper et al., tested approaches to this new “patient” profile, most notably residential programmes with long-term support. 

Definition: In the 1990s, the term Dual Disorder (also dual or comorbid diagnosis: hereafter DD) began to be used more specifically to designate the coexistence of a severe mental disorder (mainly schizophrenia) and a Substance Use Disorder (hereafter SUD). In the same years it was already seen that drug use in people with SMD is one of the variables that best predicts the prognosis of schizophrenia [2]. 

Characteristics: Firstly, DD is notable for its high prevalence, estimated at 30-50% of people with MDD; for these people the lifetime risk of developing a substance abuse disorder is 3 times higher than in the general population [3]. 

Secondly, DD is associated with a course with serious complications in the prognosis and evolution of MSD, such as: 

  • Increased violent behaviour and suicide [4]
  • Increased number of hospitalisations [2]
  • Loss of home [5]
  • Worse adherence to treatment [6]
  • More frequent tardive dyskinesias [7]
  • Increased risk of acute dystonia [8]
  • Increased disorganisation [9]
  • Worse prognosis [10]
  • More frequent and more treatment-resistant hallucinations [11]
  • More depressive symptoms [12]
  • Other health problems: AIDS, etc., [5]
  • Worse quality of life [13]
  • Increased use of services (hospital, emergency) and higher cost [14] 

Thirdly, the contradiction in the relationship between psychosocial rehabilitation and drug use. People with schizophrenia and a predominance of negative symptoms are less exposed to the risks (and opportunities) of their community, including the supply of drugs. Psychosocial rehabilitation processes aim to reverse disability and increase community integration, which leads to increased accessibility to drugs. In other words, the risk of drug use in a person with SMD may increase if he/she enters rehabilitation treatment. This risk is higher if the person has a history of drug use, as a history of drug use is one of the best predictors of new drug use. 

Studies have described the profile of people with SMD who use drugs as having less negative symptomatology, being more cognitively and socially preserved, which is very necessary for the drug-taking process. Wherewith, many people with schizophrenia worsen their prognosis with drug use. This bleak prognosis of DD can be changed by cessation of drug use, in addition to appropriate antipsychotic medication and social support. This fatal coincidence - those who would have a better prognosis are made worse by drug use - makes the detection and treatment of people with DD so important at any moment in their treatment.


Many mental disorders are associated with increased comorbidity with SUD compared to the general population. The most severe psychiatric disorders have the highest rates of substance-related disorders. In the most extensive research conducted so far in the general population in relation to this comorbidity [3], the lifetime rate of drug-related disorder in the general population was approximately 17%, compared to 47% in people with schizophrenia. As mentioned above, the prevalence of DD varies between studies, but it can be stated that around 25-35% of people with MDD have a concomitant SUD at the present time and around 50% at some point in their history [15]. Another important study on substance use and psychosocial functioning in schizophrenia [16] found that out of 1,460 participants 23% were substance users and 37% had SUD.


SD is more common in males and in young people, with the first psychotic episode occurring earlier than in non-users. It is more frequent in lower socio-economic levels [5]. Use is lower in those patients in whom negative symptoms predominate [13]. On the other hand, we know that the evolution of DD can be more favourable if drug use is abandoned and if, in addition, they receive antipsychotic medication and social support [10]. Compared to abstainers, substance users have higher psychosocial functioning so that people with drug use (without SUD) and people with SUD show higher or equivalent psychosocial functioning than abstainers (except those who used cocaine) [16]. This ambivalence of DD implies that drug use in people with SMD may be filtering out people with good prognostic characteristics

DD Evaluation

The evaluation of DD is multidimensional, addressing the relevant issues for this population (effects on symptoms, compliance with treatment, household stability, etc.,) and should include longitudinal follow-up with recording of consumption values. Among the difficulties of assessment, drug use in schizophrenia is underestimated or underestimated by professionals [17], with under detection reaching an estimate of 50% or higher (84% in the emergency department) [18]. Another difficulty in evaluation is that some people with DD are not able to describe their consumption habits, may be prone to self-report problems (recall of details, demand-driven responses, etc.,) and to cognitive, psychotic and affective distortions. People with DD are often reluctant to talk about their drug use, because they expect sanctions, or because it is not accepted in their social circle. It is also a major obstacle that standard evaluation instruments (for the general population) do not fit people with MDD. The dimensions, patterns of use, consequences of use, dependence syndrome and subjective distress are quite different for people with MDD compared to people without a mental disorder [17]. 

Evaluation of DD involves exploring its multiple dimensions, for which we have a series of instruments for the evaluation of drug use, which can be classified in the following sections [15]:

  • Instruments for general or global evaluation
  • Detection or screening instruments
  • Instruments that assess the severity of dependence
  • Clinical rating scales
  • Descriptive frequency/quantity records
  • Relapse prevention and assessment of risk of abuse
  • Motivation and readiness to change
  • Multidimensional 

The choice of the most appropriate method or instrument will depend on the purpose of the evaluation, cost/benefit relation, professional qualification, care pressure, etc.

Evaluation Methods and Instruments

Screening instruments are defined by their sensitivity to detect low levels of substance abuse but cannot determine a range of use or dependence. Therefore, screening instruments are more appropriate for the general population or clinical population in short-stay units (emergency department, short stay) detecting the potential presence of SUD. Screening instruments used in persons with SUD are [15]: CAGE (General Life Habits Questionnaire) [19]; DAST (Drug Abuse Screening Test) [20]; AUDIT (Alcohol Use Disorders Identification Test) [21]; DALI (Dartmouth Assessment of Lifestyle Instrument) [22]; SDS (Severity of Dependence Scale) [23]; MIDAS (Mentally Ill Drug Alcohol Screening 2000) [24]. 

Biochemical measures are expensive and often insensitive but can be very useful if external validation or recent use is required. Such measures, like purely quantitative measures, provide measures of drug use but do not provide information on the consequences of use (psychological, occupational, social or physical). In contrast, measures of dependence severity (ASI) [25] are often insensitive to low levels of use and are more appropriate with people who have established abuse/dependence, and for monitoring treatment outcomes. Frequency/quantity measures (TLFB) [26] are used clinically for diagnostic purposes and to determine treatment goals. Structured clinical interviews (PRISM, CIDI) [27,28] have an important role in the evaluation of drug use, especially in clinical populations, where history of use and current use are essential for diagnostic establishment, care provision and treatment. 

The use of instruments that evaluate the stages of motivation for change reminds professionals of the longitudinal nature of the process and allows them to identify the treatment options that are most appropriate for the patient at each point in time. Instruments recommended for people with SMT are: SOCRATES [29]; URICA [30]; SATS [31]. The most practical recommendation for DD evaluation is to conduct a careful and respectful interview with the user and collateral informants (these with the user’s agreement). Different evaluation instruments can complement the information from the interview according to their different purposes, methods, needs, timing, objectives, device and training of the practitioner.


Effective treatment of DD requires a diversified offer of therapeutic resources addressing the different needs of people with DD [32,33]. From an evidence point of view (Cochrane) no support has been found for psychosocial treatment over standard care [34]. Still, most studies support Integrated Models and integration of services as more effective [35]. Integrated Treatment models address both disorders together and different treatment options can be found in the literature [36,37]: MTAS, BTSAS; STAR; 12 Steps; SMART; TAU; IDDT; FMI (family); etc. According to Ortega-Fons’ recent review of treatment studies for DD, [36] Integrated Dual Disorder Treatment (IDDT) [38] would be the most effective for schizophrenia with SUD and for improving quality of life. The treatments with the best results are outpatient, integrated model, multidisciplinary team and aiming at psychosocial integration. An overview of these DD treatments that have undergone efficacy studies can be found in table 1 [36]. 


Treatment and Intervention Format




Treatment Components

Bellack et al., [39]

Comparison of two integrated treatments


- Group


6 months

(2 per week)

Social intervention

Motivational interviewing

Social skills


Brooks y Penn, 2003


12 Steps (group)


SMART (individual)


6 months

1 per week

Manualised treatments



Relapse prevention, etc.

Hjorthoj et al.,

Comparison of two integrated treatments

Cap Opus vs TAU

- Individual


6 months

1-2 perweek

EPPIC Manual

Motivational interviewing

Assertiveness, etc.

Laudet et al.,

DTR Integrated Treatment

- Group


12 months

Psychosocial improvement

Mutual support

Spiritual support

Margolese et al.,

Non-Integrated Treatment (for schizophrenia)


Group and individual


12 months

Psychotherapy; psychoeducation

Crisis intervention

Social skills


Morrens et al.,

Comparison of two integrated treatments


Group and individual


12 months


Motivational interviewing

Relapse prevention

Skills training

Smeerdijk et al.,

Comparison of two treatments

FMI (Integrated Family Support vs. RFS (Standard Family Support)

Group and Multifamily

75 pacients


95 families

6 months


FMI: 12 group sessions

RFS: 2 per month

Xie et al., [38]

IDDT (Integrated)

Individual and group


3 years

Motivational interviewing


Relapse prevention

Skills training

Problem solving

Table 1: Studies on effectiveness of DD treatments (based on Ortega Fons, 2021) [36]. 

Drake, O'Neal and Wallach [32] reviewed 45 studies of psychosocial interventions for people with DD. They identified three types of intervention with consistent positive effects on SUD in people with MDD: 

  • Advisory, counselling or support groups are usually at a frequency of once or twice a week, for more than 6 months, with cognitive-behavioural techniques, tailored to the stage of treatment and recovery. They include psychoeducation and peer support within an integrated treatment. Such groups have positive effects on substance use outcomes. Group interventions are becoming more specific, standardised and effective. Bellack, Bennett, Gearon, Brown and Yang [39] found positive results with very specific interventions (cognitive performance, skills training and contingency management) for people with schizophrenia and SUD. A pertinent caveat for all clinicians is that these treatments have a high attrition rate. Therefore, the evidence shows that group counselling and advice groups have positive impacts on substance use and other outcomes, if people with DD are willing to attend the group
  • The contingency management technique is a behavioural intervention in which material incentives are given based on biological confirmation of drug abstinence [40]. Contingency management is effective in promoting abstinence from a variety of substances including alcohol, opioids and stimulants. Studies finding greater efficacy in contingency management look at a medium-term intervention over 4-6 months, with a focus on both substance use reduction and additional outcomes. In the review by Drake et al., [32] they found that all but one study had significant improvements in substance use outcomes as well as other functional behaviours. Therefore, contingency management appears to be a very promising intervention for addressing substance use disorder in this population. The complexity of implementing this technique in people with DD is outlined in Desrosiers, Tchiloemba, Boyadjieva, Jutras-Aswad [41] where both health professionals and service users agreed that the contingency approach could be integrated into regular DD treatment. In general, the contingency approach is more readily accepted by patients than by health professionals. The contingency approach was described by all participants as consistent with the overall treatment goals and led to patient awareness of their attendance to the group. It also suggests that the implementation of this approach should consider the needs and perspectives of the service users
  • Residential treatment for DD has been shown to be an effective intervention for homeless people as well as for very impaired substance users [33,42]. The residential component has an important impact on increasing the motivation of the user to treat his or her problems. Since the maintenance of stable remission requires people with DD to “create a new life”, long-term residential treatment may be effective in this rebuilding work. The residential treatment studies identified by Drake et al., [32] specifically targeted people unresponsive to standard (less intensive) outpatient treatment and with DD. Longer-term studies consistently found positive outcomes related to substance use, and Brunette et al., [43] demonstrated that long-term residential treatment was more durably effective on substance use outcomes. Long-term residential treatment is the only intervention that has been shown to be useful for those who do not respond to treatment as usual. An example of an Integrated Treatment programme for homeless people with DD, residential, urban, delivered by an ACT (Assertive Community Treatment) treatment team is described by McKoy et al., [42]. The programme emphasises harm reduction and motivational interventions along with staged treatment, psychoeducational programmes and relapse prevention groups 

In addition to these three interventions with consistently positive effects on DD, there are other strategies with significant impact in more concrete areas: case management, for example, improves sustainability in the community; and intervention from the justice system increases participation in treatment [32].

Future Perspectives in the Treatment of DD

Following Drake, O'Neal and Wallach [32], long-term studies show that most people with MDD recover from substance use disorders in stages, gradually, over months and years [38,44-47]. Models that identify these stages of treatment and change are clinically relevant because different interventions are effective at different stages of the recovery process [48,49]. For example, engagement or practical support interventions or motivational factors external to the subject (judicial, family, medical, etc.,) are effective in initiating contact with treatment. They may then need individual and group counselling to develop motivation to overcome SUD and the mental disorder. Once motivated, they require skills and support to manage their illnesses through skills training and support groups; and finally, when both disorders are going well, they may need relapse prevention techniques [49]. Intervention studies should focus on process and outcomes in relation to specific stages of treatment. 

In addition to these three interventions with consistently positive effects on DD, there are other strategies with significant impact in more concrete areas: case management, for example, improves sustainability in the community; and intervention from the justice system increases participation in treatment [32]. Another important factor is the fact that people with DD respond differently to a particular intervention or programme [32]. Diagnosis does not predict response to treatment, so it is necessary to identify subgroups based on their response to treatment. Xie et al., [47] have identified four subgroups: a group of fast and stable responders, a second group of fast but unstable responders, a third group of slow but steady responders and a fourth group of complete responders. Some people with DD respond quickly to counselling and support techniques, others respond slowly or not at all. The DD field needs to develop sequenced or stepped care approaches, offering less intensive and costly interventions first, and more intensive and costly interventions contingent on earlier response [48]. 

The context also determines the effectiveness or relevance of interventions. People with DD in specific settings often have special needs that require special interventions. For example, people with DD in forensic environments (or homeless, or immigrants, etc.,) have specific needs that respond poorly to services that do not take their needs into account. 

Interventions for people with DD disorders have undergone significant development over the last 30 years. Research studies show that there are consistent positive results related to various types of interventions. Positive results have been found and there is no doubt that some techniques are effective in addressing DD refractoriness. However, there are still areas that do not respond as expected by clinicians (for example, family intervention, [50] and so it is necessary to continue searching for new, probably more holistic, formulas, involving resources (socio-health, social, employment, etc.) that have a clearer impact on the needs and circumstances of these individuals. 

  • “... The current psychiatric emphasis on neurobiology is apparent in clinical approaches, journal articles and research institutes. Nevertheless, substance abuse and, particularly among dual diagnosis clients, are strongly influenced by socioenvironmental factors [44]. It has been clear for years that many of these individuals are able to be abstinent in some settings but not in others. Thus, research needs to attend to social and environmental context-the sociological point again” [32]


  1. Pepper B, Kirshner MC, Ryglewicz H (1981) The young adult chronic patient: overview of a population. Hosp Community Psychiatry 32: 463-469.
  2. Swofford CD, Kasckow JW, Scheller-Gilkey G, Inderbitzin LB (1996) Substance use: A powerful predictor of relapse in schizophrenia. Schizophr Res 20: 145-151.
  3. Regier DA, Farmer ME, Rae DS, Locke BZ, Keith SJ, et al. (1990) Comorbidity of mental disorders with alcohol and other drug abuse. Results from the Epidemiologic Catchment Area (ECA) Study. JAMA 264: 2511-2518.
  4. Drake RE, Osher FC, Wallach MA (1989) Alcohol use and abuse in schizophrenia. A prospective community study. J Nerv Ment Dis 177: 408-414.
  5. Dixon L (1999) Dual diagnosis of substance abuse in schizophrenia: prevalence and impact on outcomes. Schizophr Res 35: 93-100.
  6. Owen RR, Fischer EP, Booth BM, Cuffel BJ (1996) Medication noncompliance and substance abuse among patients with schizophrenia. Psychiatr Serv 47: 853-858.
  7. Jeste DV, Gladsjo JA, Lindamer LA, Lacro JP (1996) Medical comorbidity in schizophrenia. Schizophr Bull 22: 413-430.
  8. van Harten PN, van Trier JC, Horwitz EH, Matroos GE, Hoek HW (1998) Cocaine as a risk factor for neuroleptic-induced acute dystonia. J Clin Psychiatry 59: 128-130.
  9. Drake RE, Wallach MA (1989) Substance abuse among the chronic mentally ill. Hosp Community Psychiatry 40: 1041-1046.
  10. Dixon L, Haas G, Weiden PJ, Sweeney J, Frances AJ (1991) Drug abuse in schizophrenic patients: Clinical correlates and reasons for use. Am J Psychiatry 148: 224-230.
  11. Sokolski KN, Cummings JL, Abrams BI, DeMet EM, Katz LS, et al. (1994) Effects of substance abuse on hallucination rates and treatment responses in chronic psychiatric patients. J Clin Psychiatry 55: 380-387.
  12. Cuffel BJ, Heithoff KA, Lawson W (1993) Correlates of patterns of substance abuse among patients with schizophrenia. Hosp Community Psychiatry 44: 247-251.
  13. Addington J, Addington D (1998) Effect of substance misuse in early psychosis. Br J Psychiatry Suppl 172: 134-136.
  14. Bartels SJ, Teague GB, Drake RE, Clark RE, Bush PW, et al. (1993) Substance abuse in schizophrenia: Service utilization and costs. J Nerv Ment Dis 181: 227-232.
  15. Fernández JA (2010) Evaluación del abuso de drogas en personas con trastorno mental grave. In: Fernández JA, Touriño R, Benitez N, Abelleira C (eds.). Evaluación en Rehabilitación Psicosocial. FEARP. Brazil.
  16. Swartz MS, Wagner HR, Swanson JW, Stroup TS, McEvoy JP, et al. (2006) Substance use in persons with schizophrenia: baseline prevalence and correlates from the NIMH CATIE study. J Nerv Ment Dis 194: 164-172.
  17. Mueser KT, Drake RE, Clark RE, McHugo GJ, Mercer-McFadden C, et al. (1995) Evaluating Substance Abuse in Persons with Severe Mental Illness. Human Services Research Institute, USA.
  18. Ley A, Jeffery D, Ruiz J, McLaren S, Gillespie C (2018) Underdetection of comorbid drug use at acute psychiatric admission. Psychiatric Bulletin 26: 248-251.
  19. Skinner HA (1982) The drug abuse screening test. Addict Behav 7: 363-371.
  20. Maisto SA, Carey MP, Carey KB, Gordon CM, Gleason JR (2000) Use of the AUDIT and the DAST-10 to identify alcohol and drug use disorders among adults with a severe and persistent mental illness. Psychol Assess 12: 186-192.
  21. Babor TF, Higgins-Biddle JC, Saunders JB, Monteiro MG (1992) AUDIT, The Alcohol Use Disorders identification Test: Guidelines for use in primary health care (2ndedn). World Health Organization, Geneva, Switzerland.
  22. Rosenberg SD, Drake RE, Wolford GL, Mueser KT, Oxman TE, et al. (1998) Dartmouth Assessment of Lifestyle Instrument (DALI): a substance use disorder screen for people with severe mental illness. Am J Psychiatry 155: 232-238.
  23. de las Cuevas C, Sanz EJ, de la Fuente JA, Padilla J, Berenguer JC (2000) The Severity of Dependence Scale (SDS) as screening test for benzodiazepine dependence: SDS validation study. Addiction 95: 245-250.
  24. Minkoff K (2000) Mental Illness and Drug and Alcohol Screening (MIDAS). Unpublished manuscript. In: Cynthia MA, Geppert MD, Minkoff K (eds.). Issues in Dual Diagnosis: Diagnosis, Treatment and New Research. Psychiatric Times.
  25. McLellan TA, Cacciola JS, Fureman I (1996) The Addiction Severity Index (ASI) and the treatment services review (TSR). In: Sederer LI, Dickey B (eds.). Outcomes assesment in clinical practice. Willians and Wilkins, Baltimore, USA.
  26. Sobell LC, Brown J, Leo GI, Sobell MB (1996) The reliability of the Alcohol Timeline Followback when administered by telephone and by computer. Drug Alcohol Depend 42: 49-54.
  27. Hasin DS, Trautman KD, Miele GM, Samet S, Smith M, et al. (1996) Psychiatric Research Interview for Substance and Mental Disorders (PRISM): Reliability for substance abusers. Am J Psychiatry 153: 1195-1201.
  28. Kessler RC, Ustün TB (2004) The World Mental Health (WMH) Survey Initiative Version of the World Health Organization (WHO) Composite International Diagnostic Interview (CIDI). Int J Methods Psychiatr Res 13: 93-121.
  29. Miller WR, Tonigan JS (1996) Assessing drinkers’ motivation for change: The Stages of Change Readiness and Treatment Eagerness Scale (SOCRATES). Psychology of Addictive Behaviors 10: 81-89.
  30. McConnaughy EA, Diclemente C, Prochaska JO, Velicer WF (1989) Stages of change in psychotherapy: A follow-up report. Psychotherapy Theory Research Practice Training 26: 494-503.
  31. McHugo GJ, Drake RE, Burton HL, Ackerson TH (1995) A Scale for Assessing the Stage of Substance Abuse Treatment in Persons with Severe Mental Illness. J Nerv Ment Dis 183: 762-767.
  32. Drake RE, O'Neal EL, Wallach MA (2008) A systematic review of psychosocial research on psychosocial interventions for people with co-occurring severe mental and substance use disorders. J Subst Abuse Treat 34: 123-138.
  33. Shilony E, Lacey D, O'Hagan P, Curto M (1993) All in one neighborhood: A community-based rehabilitation treatment program for homeless adults with mental illness and alcohol/substance abuse disorders. Psychosocial Rehabilitation Journal 16: 103-116.
  34. Hunt GE, Siegfried N, Morley K, Sitharthan T, Cleary M (2019) Psychosocial interventions for people with both severe mental illness and substance misuse. Cochrane Database Syst Rev: CD001088.
  35. Mueser KT, Noordsy DL, Drake RE, Fox L, Smith LF (2003) Integrated Treatment for Dual Disorders: A Guide to Effective Practice. Guilford Publications, New York, USA.
  36. Ortega-Fons JR (2021) Tratamiento de esquizofrenia dual y calidad de vida. Revista de Rehabilitación Psicosocial (Vol-17).
  37. Roberts LJ (2001) Cómo superar las adicciones: Entrenamiento de habilidades para pacientes con esquizofrenia: Patología SENY, USA. Pg no: 240.
  38. Xie H, McHugo GJ, Helmstetter BS, Drake RE (2005) Three-year recovery outcomes for long-term patients with co-occurring schizophrenic and substance use disorders. Schizophr Res 75: 337-348.
  39. Bellack AS, Bennett ME, Gearon JS, Brown CH, Yang Y (2006) A randomized clinical trial of a new behavioral treatment for drug abuse in people with severe and persistent mental illness. Arch Gen Psychiatry 63: 426-432.
  40. Petry NM (2000) A comprehensive guide to the application of contingency management procedures in clinical settings. Drug Alcohol Depend 58: 9-25.
  41. Desrosiers JJ, Tchiloemba B, Boyadjieva R, Jutras-Aswad D (2019) Implementation of a contingency approach for people with co-occurring substance use and psychiatric disorders: Acceptability and feasibility pilot study. Addictive Behaviors Reports 10: 100223.
  42. McCoy ML, Devitt T, Clay R, Davis KE, Dincin J, et al. (2003) Gaining Insight: Who Benefits from Residential, Integrated Treatment for People with Dual Diagnoses? Psychiatr Rehabil J 27: 140-150.
  43. Brunette MF, Drake RE, Woods M, Hartnett T (2001) A comparison of long-term and short-term residential treatment programs for dual diagnosis patients. Psychiatr Serv 52: 526-528.
  44. Drake RE, McHugo GJ, Xie H, Fox M, Packard J, et al. (2006) Ten-year recovery outcomes for clients with co-occurring schizophrenia and substance use disorders. Schizophr Bull 32: 464-473.
  45. Drake RE, Mueser KT, Brunette MF, McHugo GJ (2004) A review of treatments for people with severe mental illnesses and co-occurring substance use disorders. Psychiatr Rehabil J 27: 360-374.
  46. McHugo GJ, Drake RE, Burton HL, Ackerson TH (1995) A scale for assessing the stage of substance abuse treatment in persons with severe mental illness. J Nerv Ment Dis 183: 762-767.
  47. Xie H, Drake R, McHugo G (2006) Are there distinctive trajectory groups in substance abuse remission over 10 years? An application of the group-based modeling approach. Adm Policy Ment Health 33: 423-432.
  48. Carey KB, Cocco KM, Simons JS (1996) Concurrent validity of clinicians’ ratings of substance abuse among psychiatric outpatients. Psychiatr Serv 47: 842-847.
  49. Osher FC, Kofoed LL (1989) Treatment of patients with psychiatric and psychoactive substance abuse disorders. Hosp Community Psychiatry 40: 1025-1030.
  50. Fernández JA, Baena E (2021) Psychosocial rehabilitation and family intervention for people with dual disorders. Revista Espanola de Drogodependencias 46: 101-118.

Copyright: © 2022  Fernandez JA, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Herald Scholarly Open Access is a leading, internationally publishing house in the fields of Sciences. Our mission is to provide an access to knowledge globally.

© 2023, Copyrights Herald Scholarly Open Access. All Rights Reserved!