25 research outputs found

    Comparing single and multiple imputation strategies for harmonizing substance use data across HIV-related cohort studies.

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    BackgroundAlthough standardized measures to assess substance use are available, most studies use variations of these measures making it challenging to harmonize data across studies. The aim of this study was to evaluate the performance of different strategies to impute missing substance use data that may result as part of data harmonization procedures.MethodsWe used self-reported substance use data collected between August 2014 and June 2019 from 528 participants with 2,389 study visits in a cohort study of substance use and HIV. We selected a low (heroin), medium (methamphetamine), and high (cannabis) prevalence drug and set 10-50% of each substance to missing. The data amputation mimicked missingness that results from harmonization of disparate measures. We conducted Monte Carlo simulations to evaluate the comparative performance of single and multiple imputation (MI) methods using the relative mean bias, root mean square error (RMSE), and coverage probability of the 95% confidence interval for each imputed estimate.ResultsWithout imputation (i.e., listwise deletion), estimates of substance use were biased, especially for low prevalence outcomes such as heroin. For instance, even when 10% of data were missing, the complete case analysis underestimated the prevalence of heroin by 33%. MI, even with as few as five imputations produced the least biased estimates, however, for a high prevalence outcome such as cannabis with low to moderate missingness, performance of single imputation strategies improved. For instance, in the case of cannabis, with 10% missingness, single imputation with regression performed just as well as multiple imputation resulting in minimal bias (relative mean bias of 0.06% and 0.07% respectively) and comparable performance (RMSE = 0.0102 for both and coverage of 95.8% and 96.2% respectively).ConclusionOur results from imputation of missing substance use data resulting from data harmonization indicate that MI provided the best performance across a range of conditions. Additionally, single imputation for substance use data performed comparably under scenarios where the prevalence of the outcome was high and missingness was low. These findings provide a practical application for the evaluation of several imputation strategies and helps to address missing data problem when combining data from individual studies

    A Virtual Data Repository Stimulates Data Sharing in a Consortium

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    Abstract Research data may have substantial impact beyond the original study objectives. The Collaborating Consortium of Cohorts Producing NIDA Opportunities (C3PNO) facilitates the combination of data and access to specimens from nine NIDA-funded cohorts in a virtual data repository (VDR). Unique challenges were addressed to create the VDR. An initial set of common data elements was agreed upon, selected based on their importance for a wide range of research proposals. Data were mapped to a common set of values. Bioethics consultations resulted in the development of various controls and procedures to protect against inadvertent disclosure of personally identifiable information. Standard operating procedures govern the evaluation of proposed concepts, and specimen and data use agreements ensure proper data handling and storage. Data from eight cohorts have been loaded into a relational database with tables capturing substance use, available specimens, and other participant data. A total of 6,177 participants were seen at a study visit within the past six months and are considered under active follow-up for C3PNO cohort participation as of the third data transfer, which occurred in January 2020. A total of 70,391 biospecimens of various types are available for these participants to test approved scientific hypotheses. Sociodemographic and clinical data accompany these samples. The VDR is a web-based interactive, searchable database available in the public domain, accessed at www.c3pno.org. The VDR are available to inform both consortium and external investigators interested in submitting concept sheets to address novel scientific questions to address high priority research on HIV/AIDS in the context of substance use. Keywords: common data elements, data repository Abbreviations: National Institute on Drug Abuse (NIDA), Collaborating Consortium of Cohorts Producing NIDA Opportunities (C3PNO), human immunodeficiency virus (HIV), acquired immunodeficiency syndrome (AIDS), injecting drug users (IDU), virtual data repository (VDR) Correspondence: [email protected]

    Stress Increases the Association between Cigarette Smoking and Mental Disorders, as Measured by the COVID-19-Related Worry Scale, in the Miami Adult Studies on HIV (MASH) Cohort during the Pandemic

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    Background: Smoking has been associated with mental disorders (MD). People who smoke are at a higher risk of contracting COVID-19 and experiencing more severe symptoms of the illness. This study aimed to investigate the relationship between cigarette smoking and MD before and during the COVID-19 pandemic and whether it was influenced by COVID-19-related stress in the MASH cohort. Methods: An ambispective design was used with data collected during the pandemic (July/August 2020) by the COVID-19-Related Worry Scale, a parameter for stress, and data collected at the participants’ last cohort visit before the pandemic (December 2019). Results: In our sample of 314 participants, 58.6% were living with HIV, 39.2% had MD, 52.5% smoked before, and 47.8% smoked during the pandemic. Participants with MD were twice as likely to smoke cigarettes both before (aOR = 2.02, 95% CI: 1.21−3.37, p = 0.007) and during the pandemic (aOR = 2.10, 95% CI: 1.24−3.56, p = 0.006); and experienced higher levels of stress measured by the COVID-19-Related Worry Scale (8.59 [5.0−10.0] vs. 7.65 [5.0−10.0]; p = 0.026) compared to those without MD. Participants with MD and high levels of stress smoked more days per month (20.1 [0−30] days) than those with lower levels of stress (9.2 [0−30] days, p = 0.021), and more than those with high levels of stress, but no MD (2.6 [0−30] days, p < 0.001). Conclusions: Cigarette smoking decreased in the MASH cohort during the pandemic, but increased in participants with MD and higher levels of stress

    Psychometric Data Linking Across HIV and Substance Use Cohorts

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    Psychometric data linking of psychological and behavioral questionnaires can facilitate the harmonization of data across HIV and substance use cohorts. Using data from the Collaborating Consortium of Cohorts Producing NIDA Opportunities (C3PNO), we demonstrate how to capitalize on previous linking work with a common linked depression metric across multiple questionnaires. Cohorts were young men who have sex with men (MSM), substance-using MSM, HIV/HCV cocaine users, and HIV-positive patients. We tested for differential item functioning (DIF) by comparing C3PNO cohort data with general population data. We also fit a mixed-effects model for depression, entering HIV-status and recent opioid/heroin use as fixed effects and cohort as a random intercept. Our results suggest a minimal level of DIF between the C3PNO cohorts and general population samples. After linking, descriptive statistics show a wide range of depression score means across cohorts. Our model confirmed an expected positive relationship between substance use and depression, though contrary to expectations, no significant association with HIV status. The study reveals the likely role of cohort differences, associated patient characteristics, study designs, and administration settings
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