Research Article Open Access Page et al., J Foren Psy 2018, 3:3 Research Article Journal of Forensic Psychology J o u r n a l o f F o r e n s i c P s y c h o l o g y ISSN: 2475-319X Open Access Volume 3 • Issue 3 • 144 J Foren Psy, an open access journal ISSN: 2475-319X The Measurement of Substance Use in Forensic Schizophrenia Spectrum Disorders-Initial Validation of a New Scale Louis De Page*, Raphaëlle Boursoit and Pierre Titeca Clinical Psychologist, Centre Hospitalier Jean Titeca, 11 rue de la Luzerne, 1030 Schaerbeek, Belgium Abstract Background: Mainstream substance abuse assessment schemes do not grasp the specifc consequences of substance abuse (SA) in a) schizophrenia in patients and b) forensic settings. In the current study, we present the initial validation stages of a new scale measuring substance abuse and its consequences specifcally for schizophrenia spectrum disorders (SZ) in forensic settings. Methods: This observer-rated scale was elaborated through clinical observations in a medium-secure forensic unit for SZ. This 52-item scale measures antecedents, quantitative aspects of the SA, immediate effects, reasons for use, insight, cessation attitudes, transgressions (e.g. smuggling or extortion) and consequences through all-available indications. This scale was tested in three groups of forensic patients with SZ (n=112). Results: We found good internal consistency and interrater agreement estimates, good agreement between our scale and diagnoses of SA, moderate to strong relations with clinical functioning, risk estimates and psychopathy. Prevalences reported through this new scale are congruent with international literature. Differential patterns of scores based on substance(s) being used were observed. Conclusions: This new scale appeared to grasp for the clinical variety of SA in forensic schizophrenia inpatients in psychometrically sound way. The instrument appeared to be user-friendly enough not to require specifc training or long uptake. Keywords: Schizophrenia; Forensic; Substance use; Cannabis; Stimulants; Psychosis Introduction Te assessment of substance abuse (SA) has generated a considerable body of literature and a wide array of measures have been devised. However, when it comes to measuring SA in schizophrenic subjects in forensic psychiatric settings, it gets more complicated. Interaction between schizophrenia spectrum disorders (SZ) and SA has been widely investigated [1]. A generally high prevalence of SA in SZ has been reported 50% to 86% [2-4]. Several explanations have been advanced: SA creates a vulnerability for SZ, self-medication for SZ subjects, reward defciency circuits, etc [1,2]. Clinically, it is generally accepted that SA might alleviate symptoms in the short term, but worsen the overall course of SZ. Te precise pattern of the benefts and harm depends on the substances being used. For example, cocaine alleviates negative symptoms afer recent use [5] but is associated with more physical health diagnoses, more frequent mental health admissions, and housing instability [4,6]. Cannabis alleviates anxious symptoms in the short term, but worsen (positive, thought disturbance and hostility) SZ symptoms aferwards, and creates a bidirectional association between the likelihood of SA and symptom severity in the long run [7]. Beside efects on symptoms, cannabis use was associated with higher rates of psychotic relapse [8], and appeared to consolidate transient psychoses into SZ [4,6]. In general, SA in SZ has also been associated with non-compliance [9] and higher rates of readmissions [10]. In forensic context, the assessment of SA is especially important given its precipitating efect for violence [11,12]. Te complex intertwinement between SZ, SA and violence outreaches the scope of this article, but diferentiating the pathways to violence is crucial. Summarily stated: some forensic patients have a longstanding history of antisocial behavior where SA and SZ came afer the onset of violence *Corresponding author: Louis De Page, Centre Hospitalier Jean Titeca, 11 rue de la Luzerne, 1030 Schaerbeek, Belgium Received July 18, 2018; Accepted July 31, 2018; Published August 13, 2018 Citation: Page LD, Boursoit R, Titeca P (2018) The Measurement of Substance Use in Forensic Schizophrenia Spectrum Disorders-Initial Validation of a New Scale. J Foren Psy 3: 144. Copyright: © 2018 Page LD, 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. so called “early starters” [13]. Oppositely, “late starters” have SZ (and SA) prior to violence. SA might also lead indirectly to criminogenic environments, which in turns augments the likelihood of violence which is closer to “early starters” [11]. SA might directly exacerbate delusions or hostility, diminish the efectiveness of medication, and lead to violence (which is likelier for “late starters”). Terefore, an assessment of SA in forensic SZ should record antecedents in order to diferentiate pathways to violence. Antecedents are closely linked to behavioral and lifestyle psychopathic traits [14,15]. Monitoring and assessing SA in forensic schizophrenic subjects has specifc implications that would not be measured in substance-focused questionnaires. Tese include breaking hospital rules by smuggling substances, trafcking, jeopardizing treatment progression, augment violence, etc. In Belgium, as in many other countries, forensic patients are ofen on conditional release when they enter care and when they are rehabilitated in community settings. Tis conditional release can be revoked if SA is detected, or if SA ushers an infringement release conditions (e.g. violence, skipping probation, etc.). Aim and formal hypotheses Our aim is to create a reliable and valid scale assessing substance use in forensic schizophrenia spectrum patients. Our new scale should accurately identify SA in SZ patients, and patients identifed as such