Browsing by Author "Copeland J"

Now showing 1 - 3 of 3
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    Cannabis use and disorder transitions among a mixed community sample of at-risk adolescents and adults: A prospective New Zealand study
    (Bentham Open, 29/11/2013) Bashford J; Copeland J; Flett RA
    Introduction and Aims: The trajectories of cannabis use disorder (CUD) require more comprehensive delineation to expedite recognition of incubating dependence among high-risk users. This study examined baseline cannabis use and CUD over 12 months using DSM-IV/ICD10 diagnoses to distinguish transition groups. Design and Methods: In a prospective naturalistic design, 194 heterogeneous cannabis users (128 adolescents, 66 adults) aged 13-61 years were voluntarily recruited and assessed at baseline, and then re-assessed 12-months later. Results: Most participants met criteria for a baseline CUD (70% dependence, 20% abuse), 12 adolescents were 'diagnostic orphans', and 5 symptom-free. At follow-up, 25% adolescents reported using less, 6% the same level, and 69% using more cannabis. Significantly increased symptoms and dependence severity were reported, with no adolescent/adult differences evident. Three diagnostic transition groups were identified. While 84% adolescents (n=108) remained stable, 5% (n=7) had improved, 10% (n=13) had deteriorated. ‘Deteriorators’ scored significantly higher than ‘improvers’ on cannabis use, symptoms, and dependence severity measures. A subjective loss of control over cannabis use was among the earliest DSM-IV features among younger users on a trajectory towards dependence. Most participants (79%) anticipated difficulty trying to reduce/quit their use. Discussion and Conclusions: Younger adolescents can rapidly develop cannabis dependence, reporting similar and equally severe symptoms as longer-term adult users. Impaired control over use occurs early in trajectories towards dependence. The seeming intractability of problematic cannabis use calls for concerted cannabis screening and early intervention (SEI) efforts at an earlier age to avert or reduce harmful consequences of cannabis use in the community.
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    CUPIT: A measure of current and developing cannabis-related problems
    (2010) Bashford J; Flett R; Copeland J
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    The Cannabis Use Problems Identification Test (CUPIT): Development, reliability, concurrent and predictive validity among adolescents and adults
    (John Wiley & Sons, 2010) Bashford J; Flett R; Copeland J
    AIMS: To describe the empirical construction and initial validation of the Cannabis Use Problems Identification Test (CUPIT), a brief self-report screening instrument for detection of currently and potentially problematic cannabis use.DESIGN: In a three-phase prospective design an item pool of candidate questions was generated from a literature review and extensive expert consultation. The CUPIT internal structure, cross-sectional and longitudinal psychometric properties were then systematically tested among heterogeneous past-year users.PARTICIPANTS: Volunteer participants were 212 high-risk adolescents (n = 138) and adults (n = 74) aged 13-61 years from multiple community settings.MEASUREMENTS: The comprehensive assessment battery included several established measures of cannabis-related pathology for CUPIT validation, with DSM-IV/ICD-10 diagnoses of cannabis use disorders as criterion standard.FINDINGS: Sixteen items loading highly on two subscales derived from principal components analysis exhibited good to excellent test-retest (0.89-0.99) and internal consistency reliability (0.92, 0.83), and highly significant ability to discriminate diagnostic subgroups along the severity continuum (non-problematic, risky, problematic use). Twelve months later, baseline CUPIT scores demonstrated highly significant longitudinal predictive utility for respondents' follow-up diagnostic group membership. Receiver operating characteristic (ROC) analysis identified a CUPIT score of 12 to be the optimal cut-point for maximizing sensitivity for both currently diagnosable cannabis use disorder and those at risk of meeting diagnostic criteria in the following 12 months.CONCLUSIONS: The CUPIT is a brief cannabis screener that is reliable, valid and acceptable for use across diverse community settings and consumers of all ages. The CUPIT has clear potential to assist with achievement of public health goals to reduce cannabis-related harms in the community.