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Best Practices - Concurrent Mental Health and Substance Use Disorders

Best Practice in Screening for Substance Use and Mental Health Disorders

General Issues in Screening

Attempts to treat substance abuse among people with mental health disorders, and vice versa, must begin with recognition.169,41 The purpose of screening is not to determine the complete profile of psychosocial functioning and needs, or to make a diagnosis; but rather to identify whether the individual may have a mental health or substance abuse problem that warrants more comprehensive assessment.

In general, the goal is to have screening instruments that are brief; do not identify a high proportion of false positives; and have good reliability and validity (see Appendix E for definitions of these and other terms related to screening instruments). As noted above the needs and opportunities for identification vary considerably across different types of mental health and substance abuse treatment settings. It is not possible to recommend one approach or screening tool. Therefore, the recommendations are organized into two levels of effort; with the second level requiring more time and expertise than the first, but yielding potentially greater benefits in terms of reliability and validity. Further, this is an area of research that is expanding rapidly and several new screening instruments are available or on the horizon, but which have yet to be validated in either the substance abuse or mental health population. Where appropriate new instruments that are being developed or tested, and which may be appropriate for people with concurrent disorders in either or both populations are mentioned.

In this review the work of Dr. Kate Carey and colleagues40,170,178 has been drawn on for screening. The seminal work of Drs. Robert Drake, Kim Mueser and colleagues has also been valuable.156 The reader is encouraged to review the reports and literature reviews published by these research teams. Several of their reports are listed in Appendix A, and in the References.

The following points concern terminology and some other general issues:

  • while it is important to have screening tools that have excellent psychometric properties, a distinction can be made between what is needed for clinical decision-making, compared to what might be needed for a highly controlled research study. In other words, even though there may be no proven screening tool available at present which will work in all settings, there is still value in asking a few simple questions, or otherwise having a high index of suspicion using readily available information. We include these approaches under Level I screening strategies;
  • in an integrated system it will be critical to have the linkage between services for screening and assessment well-established and monitored in order to reduce the burden on the consumer to "retell their story". This was an important theme identified in the consumer focus groups;
  • research generally supports the value of getting information about alcohol and drug use from different sources to corroborate information obtained solely from the self-report of the consumer. Although self-reported information about alcohol and drug use can be considered reliable and valid in some contexts, self-reports are not as trustworthy in other contexts (see Carey170 and Carey & Correia41). For example, concerns about self-report may be particularly important when working with a person to be admitted to a psychiatric service and for whom admission of substance abuse has potential negative consequences in terms of ongoing treatment and support (e.g., loss of housing). It is generally acknowledged that laboratory tests which screen for substance use disorders on the basis of biochemical markers are much less sensitive and useful with people with concurrent disorders than are collateral reports from family, friends or past records;41
  • there is a preference for screening tools and procedures in the public domain; that is they are available at no cost to the service provider;
  • services which are providing support to a consumer for an extended period of time, such as an intensive case management program or a clubhouse for people with severe mental illness, will be able to monitor the situation over a longer period of time. Thus, screening need not only occur at intake into the service. The judgment of the case worker can have a high predictive value as the consumer becomes better known and trust is established;171
  • in the mental health field there is an important distinction between diagnostic screening instruments and those based on psychological distress/functioning. Similarly, for substance use disorders, there are diagnostic screening instruments and there are those based on consequences or pattern of substance use. Both methods among the Level II screening approaches are considered;
  • most screening tools for substance use disorders are focused on either alcohol or other drugs but not both. Given the common pattern of multiple substance use, one can miss important substance-related problems if one screens only for alcohol problems or only for drug problems. Few instruments are available which screen for both alcohol and other drug problems. CAGE-AID172 and the Dartmouth Assessment of Lifestyle Instrument (DALI: Rosenberg et al.173) are notable exceptions;
  • there are important developmental issues to consider when selecting a screening tool or procedure for consumers of different ages. Some instruments are designed specifically for adolescents;174,175
  • finally, there are critical issues related to the use of different screening instruments within different cultural sub-groups without first having tested their psychometric properties and appropriateness in the particular sub-group of interest. Other practical and methodological issues concern the literacy level of the consumer; the extent to which they need support in answering screening questions; and the influence of lending support to the person in completing the questions on the reliability and validity of the answers (e.g., impact of wanting to answer in a socially desirable way41).

Screening for Substance Use Disorders

a) Level I Screening Procedures

Within this level four alternatives are described. These alternatives require very little time and effort on the part of clinicians/support workers during the initial contact with the consumer, or within the context of an official intake process. Sensitivity and specificity values derived with a group of people with concurrent disorders are not available for all the alternatives listed. However, such measures and approaches may still have value as part of a clinical decision-making process, especially in settings where more psychometrically sophisticated approaches may not be appropriate during the early period of contact or intake to the program (e.g., acute crisis settings). It is better to cast a wide net in the screening process and subsequently rule out a substance use disorder on the basis of further assessment.

Index of suspicion: If other methods are not feasible or appropriate, it is possible to use a simple checklist of behavioural, clinical and/or social indicators that together can raise the suspicion that the person has a substance use disorder. The following have been considered as common consequences of substance abuse in people with severe mental illness (Group 2). Examples are given in Appendix F.

  • housing instability;
  • difficulty budgeting funds;
  • symptom relapses apparently unrelated to life stressors;
  • treatment non-compliance;
  • prostitution, other sexual acting out or sexual deviance;
  • social isolation;
  • violent behaviour or threats of violence;
  • pervasive, repeated social difficulties;
  • sudden unexplained mood shifts;
  • employment difficulties;
  • suicidal ideation or attempts;
  • hygiene and health problems;
  • cognitive impairments;
  • legal problems.

On the basis of current practice wisdom the following should be added to this list:

  • avoidance of disclosure (of likely concurrent disorders) for fear of being admitted to inpatient psychiatry;
  • repeated self-harm in the absence of clear situationally relevant stressors;
  • a cyclic history of substitute or replacement addictions.

Asking a few questions: Some research has shown that the response to a straightforward question about previous problems related to alcohol is highly correlated with the results of more detailed screening instruments.176 The evidence on the value of this approach with people with concurrent disorders is mixed. The reluctance of people to be completely forthright in such self-diagnosis has been noted, and this may be particularly true upon first presentation to some mental health settings where no trusting relationship has yet been established between the consumer and the provider. Indeed, this was identified as a theme in the consumer focus groups. Drake et al.156 warn of the difficulty people with severe mental illness may have in perceiving the relationships between substance use and psychosocial difficulties, and of the tendency to provide socially desirable answers. On the other hand, Barry et al.171 compared consumer self-report and case manager ratings. They found the consumer ratings on some of the questions to be more predictive of a substance use disorder as determined by DSM-III-R criteria. The best predictor of a substance use problem by the consumer was their perception that others were concerned about their substance use (70% sensitivity: 88% specificity; 76% positive predictive value; and 84% negative predictive value). It is cautiously recommended that the three following questions be used as potential Level I screening questions for substance use disorders in mental health settings when other approaches are considered inappropriate. A positive response to any one question should indicate the need for further investigation.

Have you ever had any problems related to your use of alcohol or other drugs? (yes/no)

Has a relative, friend, doctor or other health worker been concerned about your drinking or other drug use or suggested cutting down? (yes/no)

Have you ever said to another person "No, I don't have [an alcohol or drug] problem, when around the same time, you questioned yourself and FELT, "Maybe I do have a problem?" (yes/no)

A brief screening instrument: The third approach for Level I screening is based on the CAGE questionnaire,177 and a modification known as CAGE-AID that incorporates both alcohol and other drugs.172 They are considered Level I measures because of their brevity; being comprised of four items which can be routinely incorporated into a formal intake process or a discussion with a consumer seeking help. The CAGE has been validated with a sample of people with severe mental illness and has reasonably high sensitivity and specificity.156,178 Wolford et al.,179 however, compared several screening measures for substance use disorders for people with severe mental illness and, while the CAGE performed better than other approaches such as clinical variables, laboratory tests and collateral reports, it still yielded only modest sensitivity (60.9%) and specificity (69.5%).*The CAGE and CAGE-AID collect information related to lifetime rather than current substance use problems and some may also find this to be a limiting factor.

Case manager judgment: In mental health settings which maintain contact with the consumer for several weeks, months or even years, case managers can ask themselves a few questions to screen for a substance use disorder.171 In the study by Barry et al.171 the best predictor of a consumer's meeting the DSM-III-R criteria for a substance use disorder was the one question: "Do you think the client has ever had a drinking or other drug problem? Would you say definitely, probably or not at all?"

A relatively new brief screening tool for alcohol use disorders may hold promise for identifying people with concurrent disorders in mental health settings on the basis of further research. This instrument, known as RAPS4, has been developed as a brief screening tool for problematic drinking in emergency room settings.181 It is comprised of four questions related to: Remorse, Amnesia, Performance and Starter (i.e., morning drinking). In emergency settings, a positive response to any one item has been found to have high sensitivity (93%) and specificity (87%). The instrument has also performed well across gender and ethnic sub-groups. Although promising it needs to be validated in mental health settings.

* On some criteria, the TWEAK screening instrument for alcohol problems180 performed better than the CAGE. However, the CAGE has been better researched with people with concurrent disorders and has been adapted to relate to both alcohol and drug problems.

b) Level II Screening Procedures

Within this level there are four alternative instruments.* They require somewhat more time and effort to incorporate into routine practice than the Level I alternatives (e.g., there are too many items to commit to memory with a simple mnemonic device such as with the four CAGE questions). However, all measures are still quite brief and easy to administer by interview or self-completion. Also, all the instruments noted below have been validated with people with mental health disorders and they are all in the public domain.

Dartmouth Assessment of Lifestyle Instrument (DALI):173 This instrument is the only screening instrument for substance use disorders that has been developed specifically for use with people with severe mental illness. It consists of 18 items that come from various existing screening tools. It was developed to be interviewer assisted. Eight items predict drug use disorders, nine predict alcohol use disorders. Two items overlap alcohol and drug use disorders. Results suggest it is reliable over time and across interviewers, and that it is more sensitive and specific than several measures including the MAST, TWEAK, CAGE or DAST.173

Michigan Alcoholism Screening Test (MAST):182 Teitelbaum and Carey178 provide a comprehensive review of substance abuse assessment and screening measures applicable for people with severe mental illness. Their review includes many studies including the MAST,182 and its shorter version (SMAST):183 (see also184). The MAST was also one of several screening measures evaluated by Wolford et al.179 While the instrument has been used extensively with people with severe mental illness, it is limited in comparison to the DALI since a separate screening tool will need to be used for drugs other than alcohol** (e.g., the Drug Abuse Screening Test (DAST).185 It also gathers lifetime versus current information. A score of five or more indicates alcoholism; a score of four is suggestive and a score of less than four indicates non-problematic drinking. The SMAST is recommended over the full MAST due to its brevity (12 items). In the recent study by Wolford et al.179 the much shorter self-report scales such as the CAGE or the TWEAK performed equally well as the MAST, if not better. However, all the brief self-report screening tools missed 25% to 40% of the people with alcohol disorders. While the results obtained in other studies with the MAST have been better than found in this recent study (e.g., 86.8% sensitivity noted by Drake et al.156) the MAST or the SMAST need to be complemented by other information such as collateral reports and behavioural observation.

Drug Abuse Screening Test (DAST):185 The DAST is similar to the MAST in that it is based on consumer’s self-report and is not diagnostic; being based more on the consequences related to drug use than drug dependence per se. The items can be either interviewer or self-administered. In contrast to the MAST, the DAST items refer to the past 12-months rather than lifetime. Recent research on the DAST with psychiatric outpatient populations has confirmed the internal scale properties with this group and established acceptable test-retest reliability, criterion-related validity, sensitivity and specificity.186,187 In these studies the briefest version of the DAST (10 items) also performed adequately as a screening instrument. The authors of these recent studies recommend a cut-off point of between 2-4 positive items on the DAST-10 as warranting further substance abuse assessment. However, they also point out that different cut-off points can be used depending on the clinician’s interest in maximizing sensitivity or specificity. The cut-off point of 2 positive items was reported as achieving a good balance. Maisto et al.187 also point out that the positive predictive value of the DAST-10 was low compared to that reported for the DALI by Rosenberg and colleagues.173 This was attributed to the comparatively low base rate of current drug use disorders in their sample. This underscores the importance of considering the underlying prevalence of substance use disorders in the mental health setting when evaluating the appropriateness of a screening tool. For example, lower prevalence rates will lead to lower predictive value. A tool with low predictive value in a given setting can still be useful if a goal is to limit the number of individuals for whom more extensive, and more costly, assessments of substance use problems would be conducted. The appropriateness of this strategy versus the one of maximizing the number of people screened positive, including false positives, will need to be determined within individual settings and treatment systems.

The Alcohol Use Disorders Identification Test (AUDIT):188 The AUDIT is a well-known, 10-item self-report screening instrument designed to identify people for whom the use of alcohol puts them at risk for negative alcohol-related consequences, or who are experiencing such consequences. Its performance has recently been evaluated with people with severe mental illness.187 The time reference for the AUDIT items is the past year, although a few items have no specific time referent. It can be interviewer or self-administered. Maisto and colleagues187 confirmed the value of the AUDIT in identifying people with alcohol use disorder, or expressing symptoms of that disorder, in the past year. Estimates of sensitivity ranged from .95 to .85 depending on the cut-point used. Specificity ranged from .65 to .77. Consistent with the use of the AUDIT in other settings189 a cut-point of 7 or 8 struck a good balance between sensitivity and specificity when using the diagnostic criteria of DSM-IV as the standard for comparison.

* The project team is aware of the common use of the Substance Abuse Subtle Screening inventory (SASSI) as a screening and assessment tool used by many addictions programs in Canada. The limited validation data for the SASSI generally, and for application with people with concurrent disorders specifically, preclude our recommending it in the present context.

** As with the CAGE instrument a SMAST-AID (i.e. And Including Drugs) has been developed. However, it has not been tested with a sample of people with mental health disorders. Given the potential for confusion in the use of the term "drug use" the measure can not be recommended for use with this population at this time.

Level II Screening Measures for Substance Abuse

All of the above screening tools are based primarily on consequences related to alcohol or drug use and the item responses do not map onto DSM-IV criteria. One brief tool that is available does provide this mapping and it also covers both alcohol and other drugs with the same set of items. The measure, however, has not yet been extensively evaluated, in particular with people with concurrent disorders. This set of 16 items (Substance Abuse and Dependence Scale: SADS) is a scale within the Global Appraisal of Individual Needs (GAIN:190). The SADS provides a useful screen for dependence (tolerance, withdrawal, inability to control use) and abuse (consequences of use) based on DSM-IV criteria. It also produces a symptom count score which can be used to monitor change over time.

In addition, the Psychiatric Screener described in the next section for screening for mental health disorders, also provides a list of items that map onto the DSM-IV criteria for substance abuse and dependence.

c) Summary:

There are many alternatives for screening for substance abuse among people presenting to mental health services. The specific strategy selected may depend on the time and resources available. Asking a few simple questions or using a basic index of suspicion will be better than not giving any attention at all to substance abuse issues. It is also recommended that the results of brief screening tools (e.g., CAGE-AID) be complemented by corroborating information from different sources. Case manager ratings may be particularly helpful in those services with ongoing contact with the consumer. The DALI is the preferred tool for screening for substance abuse among people with severe mental illness.

Best Practice Recommendation
  • It is recommended that all people seeking help from mental health treatment services be screened for co-occurring substance use disorders. This advice is organized around Level 1 and Level II approaches that can be tailored to the type of setting and the time and resources available.
  • Level I approaches include:
    • using an index of suspicion
    • asking a few questions
    • using a brief screening instrument
    • using case manager judgment
  • Level II approaches include the:
    • Dartmouth Assessment of Lifestyle Instrument (DALI)
    • Short Michigan Alcoholism Screening Test (SMAST)
    • Drug Abuse Screening Test (DAST)
    • Alcohol Use Disorders Identification Test (AUDIT)

Screening for Mental Health Disorders

a) Level I Screening Procedures

Within this level, there are two alternatives that require very little time and effort on the part of clinicians/therapists during the initial contact with the consumer, or within the context of an official intake process. As with the Level I procedures for screening for substance abuse in mental health settings, reliability, validity, sensitivity and specificity values are not available for these procedures. However, suggestions are based on current practice wisdom and may still have value as part of a clinical decision-making process, especially in settings where more psychometrically sophisticated approaches may not be appropriate during the early period of contact or intake to the program (e.g., withdrawal management settings).

Index of suspicion: If other methods are not feasible or appropriate, it is possible to use a simple checklist of behavioral, clinical and/or social indicators that together can raise the suspicion that the person has a mental health disorder and for whom a subsequent mental health assessment is needed. Consistent with the TIP concurrent disorders protocol,24 the following ABC checklist for a mental health status exam is recommended.

  • Appearance, alertness, affect, and anxiety:

    Appearance: General appearance, hygiene, and dress.
    Alertness: What is the level of consciousness?
    Affect: Elation or depression: gestures, facial expression, and speech.
    Anxiety: Is the individual nervous, phobic, or panicky?
  • Behavior:

    Movements: Rate (hyperactive, hypoactive, abrupt, or constant?).
    Organization: Coherent and goal-oriented?
    Purpose: Bizarre, stereotypical, dangerous, or impulsive?
    Speech: Rate, organization, coherence, and content.
  • Cognition:

    Orientation: Person, place, time, and condition.
    Calculation: Memory and simple tasks.
    Reasoning: Insight, judgment, problem solving.
    Coherence: Incoherent ideas, delusions, and hallucinations?
  • Asking a few questions: It is cautiously recommended that the three following questions be asked if other approaches are considered inappropriate in a particular setting:

    Have you ever been given a mental health diagnosis by a qualified mental health professional? (yes/no)

    Have you ever been hospitalized for a mental health-related illness? (yes/no)

    Have you ever harmed yourself or thought about harming yourself but not as direct result of alcohol/drug use? (yes/no)

    If answered forthrightly by the consumer these three questions will still no doubt miss many people with concurrent disorders, especially those with less severe mental illness. However, the questions are better than not asking any questions at all, in those settings where the application of a longer psychometrically validated screening tool may not be appropriate.

b) Level II Screening Procedures

There is a real need for a brief, validated screening instrument for mental health disorders that would be suitable for use in a wide cross-section of substance abuse treatment services. As noted earlier there is also an important distinction to be made between screening instruments that are based on measures/indicators of general psychological distress compared to those with questions that are intended to map directly onto DSM diagnostic criteria. Each approach has advantages and disadvantages. It is also important to keep in mind that the goal of the screening is to identify people who should receive a full mental health assessment at which time diagnosis would be confirmed.

One of the difficulties encountered in identifying potential screening instruments for mental health problems is that the best researched instruments tend not to be in the public domain and therefore require a fee for their use. A good example is the Brief Symptom Inventory which is a 53-item self-report short form of the SCL-90-R.191 It has been used extensively in substance abuse treatment research as a reliable and valid general screen for psychopathology. Another example is the General Health Questionnaire192 and its shorter versions (GHQ-28);193 which has also been widely used in the substance abuse field. There are also brief screening tools specific to some mental health disorders, for example the Centre for Epidemiologic Studies Depression Scale (CES-D):194 and these are cited in the later sections on specific sub-groups of people with concurrent disorders.

Psychiatric Sub-scale of the Addiction Severity Index (ASI):195 The best practice recommendation from among current alternatives in the public domain is the psychiatric sub-scale of the Addiction Severity Index. The scale is comprised of 11 items that tap into previous treatment for psychological or emotional problems; disability pension; use of medication; and experiencing various symptoms (e.g., depression, serious anxiety, hallucinations, cognition difficulties, suicide ideation) but which are not a direct result of drug/alcohol use. In addition to these 11 items, both the client and the therapist provide various ratings of problem severity. Through communication with the developers of the ASI, the following four questions can supplement the ASI Psychiatric Sub-scale in its published form.

Have you had a significant period of time (that was not a direct result of alcohol/drug use) in which you have (0=no; 1=yes):

  1. Experienced significant problems with controlling your eating (e.g. binging, purging, unable to eat) Past 30 days? _______________ Lifetime?
  2. Experienced significant problems with your sleep? (e.g. falling/staying asleep, sleeping too much) Past 30 days? _________________Lifetime?
  3. Experienced a trauma that comes back in unwanted flashbacks? Past 30 days? ________________Lifetime?

Level II Screening Measures for Mental Health

There are three promising screening tools under development:*

  • A mental health screening tool known as the Psychiatric Screener197 is being developed by the Centre for Addiction and Mental Health** in Toronto. The preliminary reliability and validity testing of the Psychiatric Screener is currently under investigation and the results to date have been very encouraging.

    The Psychiatric Screener assesses 12 dimensions of psychopathology across Axis I of the DSM. Each dimension results in a 0 to 1 scoring system, and is not continuous in terms of degree of severity. Individuals receive a gross categorization of either having the disorder or not having the disorder (to be followed by a full mental health assessment). In addition, for those who have a positive score for having the disorder, the screening instrument scores the person in terms of the disorder being current or in the past (i.e., occurred sometime before the month in which testing took place).

    The Psychiatric Screener also assesses symptoms associated with dependence or abuse of each of several classes of psychoactive substances; the items reflecting the criteria in DSM-IV.
  • In addition to the Psychiatric Screener which is diagnosis-based, another important option for screening for mental health problems based on psychological distress/functioning is on the horizon. In the GAIN assessment package mentioned earlier in the context of screening for substance use disorders,190 there is a 21-item General Mental Distress Index (GMDI) that screens for depression, anxiety and suicide ideation. It also has additional screening items for traumatic distress and external distress (e.g. ADHD, conduct disorder).198 The measure, however, has not yet been extensively validated, in particular with people with concurrent disorders.
  • Another brief mental health screening tool based on psychological distress/functioning is also in the early stages of development by Ron Kessler.199

c) Summary:

There are alternatives available for screening for mental health disorders among people presenting to substance abuse services. The specific strategy selected may depend on the time and resources available. Asking a few questions or using a checklist for mental health status will be better than not giving any attention at all to mental health issues. The psychiatric subscale of the Addiction Severity Index is recommended and should be supplemented by a small number of additional items. Promising new screening tools for mental health disorders are currently under development.

Best Practice Recommendation
  • It is recommended that all people seeking help from substance abuse treatment services be screened for co-occurring mental health disorders. The advice is organized around Level I and Level II approaches that are tailored to the type of setting and the time and resources available.
  • Level I includes:
    • using an index of suspicion
    • asking a few questions
  • Level II includes:
    • psychiatric sub-scale of the Addiction Severity Index (ASI) device

 

* Another measure known as PRIME-MD screens for psychiatric disorders but has been developed spcecifically for physicians.196 While it may have some potential value in treatment settings with a staff physician it would require some modification to be more widely applicable. Further the tool has not been tested and validated with people with concurrent disorders.

** The contact person for information about this screening tool is Mr. Wayne Skinner (1-416-525-8501, Ext. 6387)

Last Updated: 2004-10-01 Top