Department of Psychiatry and Behavioral Sciences, Duke University School of Medicine, Duke University Medical Center, Durham, NC 27710, USA.
Int J Methods Psychiatr Res. 2012 Jun;21(2):117-33. doi: 10.1002/mpr.1354. Epub 2012 Feb 20.
While item response theory (IRT) research shows a latent severity trait underlying response patterns of substance abuse and dependence symptoms, little is known about IRT-based severity estimates in relation to clinically relevant measures. In response to increased prevalences of marijuana-related treatment admissions, an elevated level of marijuana potency, and the debate on medical marijuana use, we applied dimensional approaches to understand IRT-based severity estimates for marijuana use disorders (MUDs) and their correlates while simultaneously considering gender- and race/ethnicity-related differential item functioning (DIF). Using adult data from the 2008 National Survey on Drug Use and Health (N = 37,897), Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria for MUDs among past-year marijuana users were examined by IRT, logistic regression, and multiple indicators-multiple causes (MIMIC) approaches. Among 6917 marijuana users, 15% met criteria for a MUD; another 24% exhibited subthreshold dependence. Abuse criteria were highly correlated with dependence criteria (correlation = 0.90), indicating unidimensionality; item information curves revealed redundancy in multiple criteria. MIMIC analyses showed that MUD criteria were positively associated with weekly marijuana use, early marijuana use, other substance use disorders, substance abuse treatment, and serious psychological distress. African Americans and Hispanics showed higher levels of MUDs than Whites, even after adjusting for race/ethnicity-related DIF. The redundancy in multiple criteria suggests an opportunity to improve efficiency in measuring symptom-level manifestations by removing low-informative criteria. Elevated rates of MUDs among African Americans and Hispanics require research to elucidate risk factors and improve assessments of MUDs for different racial/ethnic groups.
虽然项目反应理论（IRT）研究表明，物质滥用和依赖症状的反应模式背后存在一个潜在的严重特征，但对于基于 IRT 的严重程度估计与临床相关措施的关系知之甚少。针对大麻相关治疗入院率的上升、大麻效力的提高以及医用大麻使用的争论，我们应用维度方法来理解大麻使用障碍（MUD）的 IRT 基于严重程度的估计及其相关性，同时考虑性别和种族/族裔相关的差异项目功能（DIF）。使用 2008 年全国药物使用和健康调查（N = 37,897）的成人数据，通过 IRT、逻辑回归和多指标-多原因（MIMIC）方法检查了过去一年大麻使用者中基于 DSM-IV 标准的 MUD。在 6917 名大麻使用者中，15%符合 MUD 标准；另有 24%表现出亚阈值依赖。滥用标准与依赖标准高度相关（相关系数=0.90），表明具有单一维度；项目信息曲线显示多个标准存在冗余。MIMIC 分析表明，MUD 标准与每周大麻使用、早期大麻使用、其他物质使用障碍、物质滥用治疗和严重心理困扰呈正相关。非裔美国人和西班牙裔美国人比白人显示出更高水平的 MUD，即使在调整了与种族/族裔相关的 DIF 之后也是如此。多个标准的冗余表明，通过删除低信息量的标准，有机会提高测量症状水平表现的效率。非裔美国人和西班牙裔美国人中 MUD 发生率的升高需要研究来阐明风险因素，并改善对不同种族/族裔群体的 MUD 评估。
