Model-Robust Inference for Clinical Trials that Improve Precision by Stratified Randomization and Adjustment for Additional Baseline Variables

We focus on estimating the average treatment effect in clinical trials that involve stratified randomization, which is commonly used. It is important to understand the large sample properties of estimators that adjust for stratum variables (those used in the randomization procedure) and additional baseline variables, since this can lead to substantial gains in precision and power. Surprisingly, to the best of our knowledge, this is an open problem. It was only recently that a simpler problem was solved by Bugni et al. (2018) for the case with no additional baseline variables, continuous outcomes, the analysis of covariance (ANCOVA) estimator, and no missing data. We generalize their results in three directions. First, in addition to continuous outcomes, we handle binary and time-to-event outcomes; this broadens the applicability of the results. Second, we allow adjustment for an additional, preplanned set of baseline variables, which can improve precision. Third, we handle missing outcomes under the missing at random assumption. We prove that a wide class of estimators is asymptotically normally distributed under stratified randomization and has equal or smaller asymptotic variance than under simple randomization. For each estimator in this class, we give a consistent variance estimator. This is important in order to fully capitalize on the combined precision gains from stratified randomization and adjustment for additional baseline variables. The above results also hold for the biased-coin covariate-adaptive design. We demonstrate our results using completed trial data sets of treatments for substance use disorder, where adjustment for additional baseline variables brings substantial variance reduction

HIV, hepatitis C virus, and hepatitis B virus co-infections among injecting drug users in Tehran, Iran

SummaryObjectivesTo assess the prevalence of HIV, hepatitis B virus (HBV) and hepatitis C virus (HCV) infections and co-infections among injecting drug users (IDUs) in Tehran.MethodsA sample of 899 IDUs (861 male and 38 female) was recruited in Tehran from treatment and harm reduction facilities and from drug user hangouts in public areas in equal proportions. ELISA testing for HIV, HCV antibody (HCV-Ab), hepatitis B surface antigen (HBsAg), and hepatitis B core antibody (HBcAb) was carried out. Positive HIV tests were rechecked by Western blot.ResultsThe prevalence of HIV was 10.7%, HCV infection was 34.5%, and past or current HBV infection was 50.7%. Infection with all three viruses was seen in 6.5% (95% confidence interval 4.9–8.2) of participants. HIV/HCV, HIV/HBV, and HBV/HCV co-infections were seen in 8.7%, 7.8%, and 21.0% of participants, respectively. The rate of HCV infection among HIV-positive cases was significantly higher than in HIV-negative IDUs (80.6% vs. 28.7%, p<0.0001). There was no significant association between these infections and co-infections with gender and source of sampling.ConclusionIn general, co-infection with these three blood-borne viruses is common among IDUs. Since co-infection increases the morbidity and mortality of all infections, the observed level of co-infection in the high number of IDUs in Iran necessitates a serious comprehensive response

A Scientometric Study of Iranian Scientific Productions in the Field of ‎Substance Use and Addiction Research in the Years 2008 to 2012‎

Background: We aimed to evaluate the current status of scientific production in the field of substance use and addiction in Iran, to determine its trend and pattern during a 5 years period (2008-2012). Methods: Using relevant keywords, we searched three international databases (Web of Science, Medline, and Scopus) and two local databases (SID and Iranmedex) to locate the papers published in the field of addiction by Iranian researchers during 2008-2012. Findings: The results indicated a significant increase in the number of studies published in the field during the 5 years study period, with more than half of the papers published in the last 2 years. Results also indicated that over half (53.5%) of the papers were published in Persian-language Iranian Journals, but the rate of increase in the number of papers published in English was slightly higher than that of Persian ones. Opioid substances were found to be the topic of approximately 75% of the papers. Studies on key topics, including national surveys, evaluation of current programs, addiction in women and children, and so forth, were found to be highly lacking. Conclusion: Results suggested a significant growth in the scientific production of Iran in the field of substance use and addiction. However, considering the significance of substance use and dependence in the country, and compared to the scientific production of developed countries, the amount of research conducted in the field of addiction in Iran is still limited

Inclusion of gaming disorder in the diagnostic classifications and promotion of public health response

There are ongoing controversies regarding the upcoming ICD-11 concept of gaming disorder. Recently, Aarseth et al. have put this diagnostic entity into scrutiny. Although we, a group of Iranian researchers and clinicians, acknowledge some of Aarseth et al.’s concerns, believe that the inclusion of gaming disorder in the upcoming ICD-11 would facilitate necessary steps to raise public awareness, enhance development of proper diagnostic approaches and treatment interventions, and improve health and non-health policies

A Six-Year Follow-up of People Who Use Cannabis in Iran – A Case Series

Background: Frequent cannabis use is associated with adverse health-related outcomes. This study followed up individuals who used cannabis to assess their use and adverse event status. Methods: The eligible individuals, recruited in the Iranian Mental Health Survey (IranMHS), were contacted via telephone calls six years after the index interview. The frequency of cannabis use and the occurrence of selected adverse events were recorded. The baseline status was extracted from the index survey. If any individual was inaccessible, his/her vital status was assessed.  Findings: Of the 50 eligible individuals (all male), two had died. Moreover, from among 25 reached participants, 19 reported abstinence from cannabis in the past year, and 18 reported at least one adverse event in the past six years. Violence and imprisonment were the most common events reported.  Conclusion: Six years after the index interview, most of the participants abstained from cannabis. Besides, adverse events were common, emphasizing the need for further investigations on larger samples of cannabis users

Province-level Prevalence of Psychiatric Disorders: Application of Small-Area Methodology to the Iranian Mental Health Survey (IranMHS)

Objective: National surveys revealed a high prevalence of psychiatric disorders in Iran. Province-level estimates are needed to manage the resources and focus on preventive efforts more efficiently. The objective of this study was to provide province-level estimates of psychiatric disorders. Method: In this study, Iranian Mental Health Survey (IranMHS) data (n = 7886) was used to produce province-level prevalence estimates of any psychiatric disorders among 15-64 year old males and females. Psychiatric disorders were diagnosed based on structured diagnostic interview of the Persian version of Composite International Diagnostic Interview (CIDI, version, 2.1). The Hierarchical Bayesian (HB) random effect model was used to calculate the estimates. The mental health status of half of the participants was also measured using a 28-item general health questionnaire (GHQ). Results: A wide variation in the prevalence of psychiatric disorders was found among 31 provinces of Iran. The direct estimates ranged from 3.6% to 62.6%, while the HB estimates ranged from 12.6% to 36.5%. The provincial prevalence among men ranged from 11.9% to 34.5%, while it ranged from 18.4% to 38.8% among women. The Pearson correlation coefficient between HB estimates and GHQ scores was 0.73. Conclusion: The Bayesian small area estimation provides estimation with improved precision at local levels. Detecting high-priority communities with small-area approach could lead to a better distribution of limited facilities and more effective mental health interventions

Ambiguities in existing Iranian national policies addressing excessive gaming : Commentary on: Policy responses to problematic video game use: A systematic review of current measures and future possibilities (Király et al., 2018)

Considering the scarcity of available science and controversies around effective policies addressing gaming disorder and its health-related consequences, Király et al. have conducted a systematic review on current evidence regarding this issue. We, a group of researchers in this field, would like to express our perspective from Iran. With rapid growth of gaming, Iran seems to be facing some specific policy issues and challenges, which are going to be reviewed in this short commentary

Role of Personality Trait and Locus of Control in Predicting Death Anxiety among People Infected with Human Immunodeficiency Virus

Background and Objective: Patients who are infected with Human Immunodeficiency Virus (HIV) face extensive range of psychological problems such as death anxiety, the rate and severity of which could be affected by various factors. The aim of this study was to predict death anxiety based on personality traits and locus of control of patients infected with HIV. Materials and Methods: This descriptive correlational study was performed with participation of 100 patients infected with HIV who were referred to Behavioral Disorder Counseling Center of Imam Khomeini Hospital in Tehran by purposeful sampling method. Data were gathered by Templer's death anxiety scale, Neo’s personality traits and Rotter’s scale of locus control. Data were analyzed using step-by-step regression and correlation in SPSS-22. Results: The mean (SD) score of neuroticism was 25.1 (7.8), extraversion 28.0 (6.6), conscientiousness 33.8 (6.9), openness 24.4 (4.5), agreeableness 29.1 (5.4), and locus of control 14.1 (3.6). Among personality factors, only agreeableness had a negative and significant association with death anxiety (P<0.05, r=0.231), as death anxiety decreased with a decreased level of agreeableness. In addition, 9% of the variance of death anxiety score was predicted by personality factors. Conclusion: The study showed that personality traits could predict death anxiety of patients infected with HIV and locus of control could not predict death anxiety among these patients