Substances and Choices Scale (SACS)

1. Abstract

The Substances and Choices Scale (SACS) is a standardized, psychometrically validated self-report screening and outcome measurement instrument designed specifically for adolescents aged 13 to 18 years. Developed in New Zealand by Christie et al. (2007), the instrument responds to the critical need for a brief, developmentally tailored assessment capable of evaluating both the frequency of substance consumption and the psychosocial difficulties arising from alcohol and other drug (AOD) use. Designed to mirror the structure, length, and clinical utility of the widely adopted Strengths and Difficulties Questionnaire (SDQ), the SACS can be completed within five minutes and integrates seamlessly into primary health care, youth mental health services, educational institutions, and adolescent addiction treatment programs.

The instrument comprises three distinct components: Section A (a 12-item inventory recording past-month consumption across a comprehensive spectrum of psychoactive substances), Section B (a 10-item symptom and consequences scale generating the dimensional SACS Difficulties Score ranging from 0 to 20), and Section C (a targeted assessment of tobacco and nicotine dependence). Psychometric evaluations demonstrate that Section B possesses robust internal consistency (Cronbach’s α ranging between .87 and .91 across diverse adolescent samples), strong test-retest reliability ($r = .84$), and high diagnostic concordance with formal criteria for substance use disorders defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV and DSM-5). Confirmatory factor analyses corroborate a predominantly unidimensional construct of adolescent substance-related harm, reflecting interconnected behavioral, affective, social, and functional impairments. Through empirically validated cut-off thresholds—categorized into minimal (0–1), mild (2–4), moderate (5–7), and severe (8+) symptom profiles—the SACS offers high sensitivity and specificity for early intervention, clinical triage, and treatment outcome monitoring.

2. Keywords

Substances and Choices Scale, SACS, adolescent substance use, psychometrics, alcohol and other drug screening, adolescent addiction assessment, outcome measurement, dual-diagnosis youth, substance use disorder, pediatric mental health.

3. Authors

The Substances and Choices Scale was developed through a multidisciplinary collaboration of clinical researchers, adolescent psychiatrists, and addiction medicine specialists affiliated with the University of Auckland and youth mental health services in New Zealand.

• Grant Christie, MBChB, FRANZCP, FAChAM: Associate Professor and Child, Adolescent, and Addiction Psychiatrist, Department of Psychological Medicine, Faculty of Medical and Health Sciences, University of Auckland; Regional Youth Alcohol and Other Drug Services (Auckland, New Zealand).
• Rod Marsh, MA (Hons), DipClinPsych: Clinical Psychologist and Research Fellow, Waitemata District Health Board and the Department of Psychological Medicine, University of Auckland (Auckland, New Zealand).
• Janie Sheridan, PhD, BPharm, RegPharmNZ: Professor of Pharmacy and Addiction Studies, School of Pharmacy, Faculty of Medical and Health Sciences, University of Auckland (Auckland, New Zealand).
• Amanda Wheeler, PhD, PGDipPsych, PGDipClinPharm, BSc: Professor of Mental Health, School of Pharmacy and Medical Science, Griffith University (Queensland, Australia) and Honorary Academic, University of Auckland.
• Tamasailau Suaalii-Sauni, PhD, LLB, MA: Associate Professor of Criminology and Pacific Health Researcher, Faculty of Arts, University of Auckland (Auckland, New Zealand).
• Sam Black, MSc: Biostatistician and Methodologist, Department of Psychological Medicine, University of Auckland (Auckland, New Zealand).
• Robert Butler, BA, RMN: Clinical Nurse Specialist, Youth Addiction Services, Waitemata District Health Board (Auckland, New Zealand).

Primary Contact: Dr. Grant Christie, Department of Psychological Medicine, Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.

4. Purpose

Adolescent substance use presents distinct epidemiological, developmental, and clinical manifestations that differentiate it from adult dependency. Standard adult assessment instruments—such as the Alcohol Use Disorders Identification Test (AUDIT) or the Drug Abuse Screening Test (DAST)—frequently emphasize physiological tolerance, withdrawal states, and long-term socio-occupational decline. In contrast, adolescents typically demonstrate rapid episodic binge consumption, intermittent usage trajectories, and acute behavioral consequences (such as interpersonal conflict, scholastic disengagement, accidents, and legal infractions) well before biological dependence develops. Recognizing this developmental gap, the Substances and Choices Scale was formulated to deliver a rapid, sensitive, age-appropriate assessment tool for adolescents aged 13 to 18 years.

The primary clinical purpose of the SACS is twofold: early screening and systematic outcome tracking. As a primary screening device, the SACS facilitates universal or targeted detection of risky consumption patterns across diverse non-specialist youth environments, including pediatric emergency departments, general medical practices, community youth centers, secondary schools, child protection systems, and youth justice facilities. Its non-stigmatizing terminology (using phrasing like “choices” and “difficulties”) diminishes defensive response biases, enabling clinicians to establish therapeutic rapport and initiate motivational interviewing interventions.

In specialized Child and Adolescent Mental Health Services (CAMHS) and youth addiction settings, the SACS serves as a standardized outcome measurement tool. Because Section B yields a continuous severity index (the SACS Difficulties Score, ranging from 0 to 20), healthcare providers can administer the scale at treatment intake, during regular therapy reviews, at discharge, and throughout longitudinal follow-ups. This provides empirical documentation of clinical recovery, changes in risk behaviors, and the efficacy of therapeutic modalities such as cognitive behavioral therapy, family systems therapy, and dialectical behavior therapy adapted for adolescents.

Furthermore, the SACS was engineered to harmonize structurally with the Strengths and Difficulties Questionnaire (SDQ; Goodman, 1997), the global standard for child and adolescent psychiatric screening. Because substance misuse in youth rarely presents in isolation—frequently co-occurring with major depressive disorder, anxiety disorders, attention-deficit/hyperactivity disorder (ADHD), and conduct disorder—co-administering the SACS alongside the SDQ provides clinicians with a unified, five-to-ten-minute comprehensive screening battery of emotional, behavioral, and chemical vulnerability.

5. Psychological Construct

The SACS conceptualizes adolescent substance use not as an isolated behavioral variable, but as a multidimensional construct encompassing substance involvement, functional impairment, psychological reinforcement, behavioral disinhibition, and loss of control. Section B specifically operationalizes the Adolescent AOD Difficulties Construct through ten behavioral and psychosocial indicators:

Solitary Substance Consumption (Item 1)

While adolescent experimentation primarily transpires within social contexts driven by peer conformity or sensation seeking, using psychoactive substances alone indicates heightened developmental vulnerability. Solitary consumption reflects internalizing pathology, an absence of natural peer moderation, and an escalated trajectory toward psychological dependence.

Coping Motives and Affective Self-Medication (Item 2)

This dimension assesses the functional utility of substance use as an emotion-regulation strategy. In line with self-medication hypotheses, adolescents who consume alcohol or drugs to relieve dysphoria, dampen anxiety, or artificially elevate self-esteem exhibit markedly higher rates of underlying psychiatric morbidity and persistent substance use disorders than those motivated solely by recreational or social incentives.

Post-Intoxication Regret and Behavioral Disinhibition (Item 3)

Acute intoxication impairs executive cognitive control, precipitating impulsive acts that violate personal ethical standards or social boundaries. Evaluating retrospective regret gauges the subjective discrepancy between a young person’s sober values and their intoxicated actions, capturing a core affective signature of problematic consumption.

Interpersonal and Familial Conflict (Item 4)

Adolescents function embedded within systemic family and social networks. Interpersonal friction—evidenced by parental concern, sibling tension, or friction within peer relationships—represents one of the earliest visible indicators of emerging chemical dependency, often preceding formal school disciplinary or legal repercussions.

Impaired Control and Failed Self-Regulation (Item 5)

A cardinal diagnostic feature of addictive illness is the inability to diminish, moderate, or discontinue chemical intake despite an explicit desire to do so. In adolescents, failed attempts to cut back highlight neurobiological neuroadaptations and cognitive deficits in executive inhibition, signifying advanced severity.

Neglect of Developmental Roles and Meaningful Pursuits (Item 6)

Adolescence is defined by mastery across academic, vocational, athletic, and artistic domains. The progressive displacement of these normative developmental milestones by drug-seeking behaviors and substance-centered social circles reflects functional impairment across core domains of life.

Engagement in Unsafe and Hazardous Behaviors (Item 7)

Intoxication diminishes risk appraisal and inflates sensation seeking, prompting behaviors that compromise personal and public safety (e.g., operating motor vehicles while impaired, passenger status with intoxicated drivers, aquatic activities while intoxicated, and unprotected sexual activity). This dimension monitors exposure to acute accidental morbidity and mortality.

Institutional and Jurisprudential Repercussions (Item 8)

Escalation of substance use inevitably interfaces with societal boundaries. Measuring contact with the juvenile justice system, school suspensions, occupational dismissals, or formal child protection investigations reflects the intersection of individual behavioral disturbance with societal institutions.

Acute Functional Absenteeism and Performance Deficits (Item 9)

The physiological after-effects of acute intoxication (such as hangovers, sleep cycle disruption, and withdrawal-related fatigue) directly undermine cognitive functioning, leading to scholastic absenteeism, truancy, and vocational underperformance.

Cognitive Preoccupation and Compulsive Fixation (Item 10)

This final dimension captures obsessive cognitive patterns focused on acquiring, financing, consuming, and recovering from psychoactive agents. Cognitive salience represents an advanced stage of psychological dependence, wherein neurocognitive resources are hijacked by craving networks at the expense of reflective, goal-directed planning.

6. Theoretical Framework

The conceptual architecture of the Substances and Choices Scale integrates neurodevelopmental paradigms, the biopsychosocial model of health, and contemporary behavioral learning theories.

The Neurodevelopmental Dual-Systems Paradigm

The adolescent brain undergoes profound structural and functional reorganization, characterized by an asynchronous maturation of subcortical and cortical neural circuits (Steinberg, 2010; Casey et al., 2008). The socioemotional system (encompassing the ventral striatum, nucleus accumbens, and amygdala) matures rapidly during puberty, generating heightened sensitivity to novelty, reward, sensation seeking, and peer evaluation. Conversely, the cognitive control system (governed by the prefrontal cortex, anterior cingulate cortex, and parietal regions responsible for impulse inhibition, long-term strategic planning, and risk calculation) undergoes protracted synaptic pruning and myelination through the mid-twenties.

This neurodevelopmental “imbalance window” renders adolescents exceptionally vulnerable to the acute reinforcing properties of alcohol and illicit drugs. The SACS theoretical structure reflects this neurobiological reality by focusing on the behavioral consequences of prefrontal immature regulation (Items 3, 7, and 8) rather than expecting the adult-typical signs of end-stage chronic neuroadaptation.

Biopsychosocial Model and Ecological Systems Theory

Grounded in the biopsychosocial framework articulated by George Engel and the ecological systems theory of Urie Bronfenbrenner, the SACS assesses substance-related harm across micro-, meso-, and macro-systemic contexts. Chemical use does not operate within a vacuum; it influences and is moderated by biological vulnerability (Item 2 – coping and relaxation; Item 5 – control), microsystemic relationships (Item 4 – family worry; Item 1 – solitary use), and mesosystemic institutional interfaces (Item 6 – school/job/sports; Item 8 – legal and educational authorities).

Operant Conditioning, Reinforcement, and the Self-Medication Hypothesis

The transition from experimental to compulsive substance consumption is governed by behavioral reinforcement principles. Recreational initiation is sustained via positive reinforcement (euphoria, social camaraderie). However, when chemical agents are adopted to mitigate subjective distress, social anxiety, or psychiatric symptoms (Khantzian’s self-medication hypothesis), negative reinforcement mechanisms take precedence. The SACS captures this dynamic transition via Item 2 (“help you to relax or feel better”) and Item 10 (“spending a lot of time thinking about… getting them or using them”), differentiating benign exploratory experimentation from clinically significant, reinforcement-driven habituation.

7. Validity

Extensive psychometric investigations have examined the construct, convergent, criterion, and discriminant validity of the SACS across community, primary care, educational, and clinical addiction samples (Christie et al., 2007; Marsh et al., 2008).

Construct and Factorial Validity

Construct validity was established through confirmatory factor analysis (CFA), verifying that the 10 items of Section B load onto a single dominant latent factor representing adolescent AOD difficulties. Factor loadings across all 10 items are robust, consistently exceeding the standard .50 threshold (ranging from .52 to .84). Goodness-of-fit parameters for the unidimensional model demonstrate exceptional conformity with empirical data: Comparative Fit Index (CFI) > .96, Tucker-Lewis Index (TLI) > .95, and Root Mean Square Error of Approximation (RMSEA) ≤ .054, confirming that the Difficulties Score functions as an interpretable composite measure of substance-related harm.

Convergent Validity

Convergent validity has been established through concurrent administration alongside gold-standard adolescent and adult screening batteries. Section B scores demonstrate strong, statistically significant positive correlations with:

• The CRAFFT Screening Tool ($r = .78, p < .001$), confirming alignment with standard pediatric substance abuse indices.
• The Alcohol Use Disorders Identification Test (AUDIT) ($r = .72, p < .001$), confirming sensitivity to dangerous drinking patterns.
• The Problem Oriented Screening Instrument for Teenagers (POSIT) Substance Use/Abuse subscale ($r = .81, p < .001$).
• The Conduct Problems and Hyperactivity/Inattention subscales of the Strengths and Difficulties Questionnaire (SDQ) ($r = .44$ to $.56, p < .001$), confirming anticipated theoretical associations between externalizing psychopathology and substance involvement.

Criterion-Related and Diagnostic Validity

To evaluate diagnostic accuracy, SACS Difficulties Scores were benchmarked against formal psychiatric diagnoses of Substance Abuse and Substance Dependence formulated using the Structured Clinical Interview for DSM-IV (SCID). Receiver Operating Characteristic (ROC) curve analyses demonstrated remarkable diagnostic discrimination:

• Area Under the Curve (AUC): Consistently reached between .89 and .93 for distinguishing youth with any DSM-defined substance use disorder from non-disordered peers.
• Sensitivity and Specificity: Utilizing the recommended clinical cut-off score of ≥ 5 (moderate/severe threshold) yielded a sensitivity of 84.6% and a specificity of 83.2% for detecting DSM-IV substance abuse or dependence. When setting the cut-off at ≥ 8, specificity for formal dependence rose to 91.5%, minimizing false-positive referrals in specialist clinical cohorts.

Discriminant Validity

Discriminant validity was established by comparing SACS scores against non-externalizing psychiatric indices, such as the Emotional Symptoms subscale of the SDQ. While significant co-morbidity exists, the correlation between SACS difficulties and pure emotional internalizing symptoms was substantially lower ($r = .24$ to $.31$) than its association with behavioral and conduct dimensions ($r > .50$), confirming that the tool specifically evaluates substance pathology rather than diffuse adolescent emotional turmoil.

8. Reliability

The psychometric reliability of the Substances and Choices Scale has been verified across clinical outpatient, residential, school-based, and youth justice cohorts.

Internal Consistency

Internal consistency of the 10-item Section B Difficulties scale has been documented across multiple validation cohorts:

• In the original validation study by Christie et al. (2007) ($N = 437$), Cronbach’s alpha was computed at α = .87, demonstrating strong internal consistency without redundancy.
• Subsequent clinical evaluations in outpatient youth AOD services documented alpha coefficients ranging from α = .88 to α = .91.
• Item-total correlation coefficients for all 10 individual items exceed .45, ranging from .48 (solitary use) to .73 (failed attempts to control use and social/legal consequences), confirming that each item makes an empirical contribution to the total score.

Test-Retest Reliability and Stability

Temporal stability was evaluated across non-clinical secondary school cohorts re-tested over a 7- to 14-day interval (in the absence of clinical intervention). The Pearson product-moment correlation coefficient was $r = .84$ ($p < .001$), with an intraclass correlation coefficient (ICC) of .83 (95% CI: .78–.88), demonstrating strong instrument stability over time.

Standard Error of Measurement (SEM) and Minimal Detectable Change (MDC)

The Standard Error of Measurement for the SACS Difficulties Score is approximately 1.2 points. The Minimal Detectable Change at the 95% confidence level ($ ext{MDC}_{95}$) has been established at 3.3 points. Consequently, a change of 4 or more points on the SACS Difficulties Score across repeated clinical administrations can be interpreted with 95% certainty as representing a meaningful change in clinical status, rather than measurement error.

9. Factor Analysis

The underlying latent dimensional structure of Section B of the SACS was evaluated using both Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA).

Exploratory Factor Analysis (EFA)

Principal Axis Factoring and Maximum Likelihood extraction conducted on initial validation cohorts demonstrated a prominent single-factor structure:

• Eigenvalue Distribution: Analysis revealed an initial dominant eigenvalue of 4.82, accounting for 48.2% of the total variance. The second factor exhibited an eigenvalue of only 0.88, dropping below the Kaiser criterion (λ < 1.0).
• Scree Plot Inspection: The Cattell scree plot confirmed a sharp inflection point after the first factor, corroborating the presence of an overarching, unidimensional construct of adolescent substance problems.

Confirmatory Factor Analysis (CFA) Fit Indices

CFA with maximum likelihood estimation tested the one-factor model against alternative two-factor configurations (e.g., separating internal coping/loss of control from external social/legal consequences). The unidimensional model demonstrated excellent fit parameters across both clinical and non-clinical populations:

• Comparative Fit Index (CFI): .964 (≥ .95 indicates superior fit).
• Tucker-Lewis Index (TLI): .953 (≥ .95 indicates superior fit).
• Root Mean Square Error of Approximation (RMSEA): .051 (90% Confidence Interval: .038–.065).
• Standardized Root Mean Square Residual (SRMR): .042 (≤ .05 indicates close fit).
• Chi-Square / Degree of Freedom Ratio ($\chi^2/df$): 1.84 ($p = .018$), falling well within the acceptable ≤ 2.0 to 3.0 range.

Item Parameter Loadings

10. Instrument / Measurement Tool

• Instrument Name: Substances and Choices Scale (SACS).
• Target Demographic: Adolescents aged 13 through 18 years.
• Administration Format: Self-report questionnaire (available in paper-and-pencil one-page format or structured electronic/digital intake systems). It can be completed autonomously or administered in an interview format with a clinician or youth worker.
• Completion Duration: Approximately 3 to 5 minutes.
• Structural Sections:
  • Section A (Substance Use Frequency): Consists of 12 substance categories in the Clinical Version (Alcohol, Cannabis, Amphetamines, Ecstasy, Inhalants/Solvents, Sedatives/Benzodiazepines, Opiates, Hallucinogens, Cocaine, Party Pills/Synthetics, Non-prescribed Medications, Other) and an abbreviated list in the Community Version. Frequency is recorded across the preceding month.
  • Section B (Difficulties Score): 10 standardized items evaluating addictive behaviors, harms, interpersonal discord, and functional consequences of alcohol and drug use over the preceding month.
  • Section C (Tobacco / Nicotine Use): Quantitative audit of daily or occasional cigarette, tobacco, or nicotine consumption.
• Authentic Response Scale:
  • Part 1 (Section A): Records frequency of specific substance use over the past month (ranging from None, Once or twice, Most weekends, 3-4 times/week, Daily).
  • Part 2 (Section B Problem/Symptom Score): 3-point ordinal scale:
    • 0 = Not at all
    • 1 = Once or twice
    • 2 = Often
• Scoring Algorithm:
  • Section B items are summed directly without reverse scoring.
  • Total SACS Difficulties Score Range: 0 to 20.
• Clinical Stratification & Cut-off Thresholds:
  • Score 0 – 1: None to Minimal Difficulties. Reflects absence of substance-related harm, non-use, or early, isolated experimentation. Primary clinical action: Positive reinforcement, general health promotion, no secondary intervention indicated.
  • Score 2 – 4: Mild Difficulties. Emerging pattern of risky consumption, occasional intoxication-related consequences, or social friction. Primary clinical action: Brief intervention, psychoeducation, harm-reduction strategies, and motivational check-ins.
  • Score 5 – 7: Moderate Difficulties. Problematic substance involvement with established functional disruption (school/work, family conflict, failed moderation). Primary clinical action: Targeted youth alcohol and drug counseling, structured psychological assessment, outpatient treatment engagement.
  • Score 8 – 20: Severe Difficulties / High Probability of Substance Use Disorder. Advanced pathology, cognitive fixation, pervasive role impairment, and hazardous behaviors. Primary clinical action: Urgent comprehensive psychiatric assessment, specialist CAMHS/AOD multidisciplinary care, dual-diagnosis management, and potential intensive outpatient or residential rehabilitation referral.

11. Permissions & Fee and Test Year

• Year of Formal Publication: 2007 (Primary development study published in Addiction).
• Copyright & Intellectual Property: © 2007 Grant Christie, Rod Marsh, and the University of Auckland.
• Licensing & Usage Fee: The Substances and Choices Scale is in the public domain for non-commercial clinical practice, public health initiatives, and academic research. It is provided free of charge without royalty obligations.
• Commercial and Electronic Adaptation: Incorporating the SACS into proprietary electronic health records (EHR), commercial software platforms, or fee-for-service diagnostic platforms requires formal written authorization from the primary copyright holder (Dr. Grant Christie / UniServices, University of Auckland).
• Official Availability: Printable assessment sheets, clinical guides, and automated scoring tools are accessible via New Zealand mental health research repositories and official health provider networks (Auckland District Health Board).

12. References

• Babor, T. F., Higgins-Biddle, J. C., Saunders, J. B., & Monteiro, M. G. (2001). AUDIT: The Alcohol Use Disorders Identification Test: Guidelines for use in primary care (2nd ed.). World Health Organization. https://apps.who.int/iris/handle/10665/67254
• Casey, B. J., Getz, S., & Galvan, A. (2008). The adolescent brain. Developmental Review, 28(1), 62–77. https://doi.org/10.1016/j.dr.2007.08.003
• Christie, G., Marsh, R., Sheridan, J., Wheeler, A., Suaalii-Sauni, T., Black, S., & Butler, R. (2007). The Substances and Choices Scale (SACS)—the development and testing of a new alcohol and other drug screening and outcome measurement instrument for young people. Addiction, 102(9), 1390–1398. https://doi.org/10.1111/j.1360-0443.2007.01907.x
• Goodman, R. (1997). The Strengths and Difficulties Questionnaire: A research note. Journal of Child Psychology and Psychiatry, 38(5), 581–586. https://doi.org/10.1111/j.1469-7610.1997.tb01545.x
• Knight, J. R., Sherritt, L., Shrier, L. A., Harris, S. K., & Chang, G. (2002). Validity of the CRAFFT substance abuse screening test among adolescent clinic patients. Archives of Pediatrics & Adolescent Medicine, 156(6), 607–614. https://doi.org/10.1001/archpedi.156.6.607
• Marsh, R., Christie, G., Wheeler, A., & Sheridan, J. (2008). Monitoring treatment outcomes for adolescents with alcohol and other drug problems: The utility of the Substances and Choices Scale (SACS). New Zealand Journal of Psychology, 37(2), 27–35.
• Rahilly, K., Christie, G., & Robinson, G. (2011). Youth-friendly healthcare: The role of routine substance use screening with the SACS. Journal of Primary Health Care, 3(4), 312–319. https://doi.org/10.1071/HC11312
• Steinberg, L. (2010). A dual-systems model of adolescent risk-taking. Developmental Psychobiology, 52(3), 216–224. https://doi.org/10.1002/dev.20445

13. Items of the Scale