The biotoxic effects of heavy metals exposure in miners and non-miners.

Since little is known about the comparison of the biotoxic effects of heavy metals exposure on biochemical and hematological parameters in miners and non-miners, the current study aimed to compare the effects of arsenic (As), lead (Pb), and copper (Cu) in both groups. Demographic information and blood samples were collected from all participants and measures of As, Pb and Cu were obtained using Atomic Absorption Spectrophotometry. As and Pb mean concentrations in miners and Cu concentration were greater in non-miners. Miners also showed significantly higher level of RBC, HBG and HCT. In the adjusted model, cholesterol showed a positively association with Pb and Cu levels. Triglycerides, GGT, ALP, WBC and PLT positively and HDL-cholesterol negatively were associated with Cu. Creatinine was negatively associated with group variable. In conclusion, miners' high blood heavy metals concentrations can impact biochemical and hematological indices. These observations make monitoring of heavy metals necessary in miners.

Reinfection of farm dogs following praziquantel treatment in an endemic region of cystic echinococcosis in southeastern Iran.

Cystic Echinococcosis (CE) as a prevalent tapeworm infection of human and herbivorous animals worldwide, is caused by accidental ingestion of Echinococcus granulosus eggs excreted from infected dogs. CE is endemic in the Middle East and North Africa, and is considered as an important parasitic zoonosis in Iran. It is transmitted between dogs as the primary definitive host and different livestock species as the intermediate hosts. One of the most important measures for CE control is dog deworming with praziquantel. Due to the frequent reinfection of dogs, intensive deworming campaigns are critical for breaking CE transmission. Dog reinfection rate could be used as an indicator of the intensity of local CE transmission in endemic areas. However, our knowledge on the extent of reinfection in the endemic regions is poor. The purpose of the present study was to determine E. granulosus reinfection rate after praziquantel administration in a population of owned dogs in Kerman, Iran. A cohort of 150 owned dogs was recruited, with stool samples collected before praziquantel administration as a single oral dose of 5 mg/kg. The re-samplings of the owned dogs were performed at 2, 5 and 12 months following initial praziquantel administration. Stool samples were examined microscopically using Willis flotation method. Genomic DNA was extracted, and E. granulosus sensu lato-specific primers were used to PCR-amplify a 133-bp fragment of a repeat unit of the parasite genome. Survival analysis was performed using Kaplan-Meier method to calculate cumulative survival rates, which is used here to capture reinfection dynamics, and monthly incidence of infection, capturing also the spatial distribution of disease risk. Results of survival analysis showed 8, 12 and 17% total reinfection rates in 2, 5 and 12 months following initial praziquantel administration, respectively, indicating that 92, 88 and 83% of the dogs had no detectable infection in that same time periods. The monthly incidence of reinfection in total owned dog population was estimated at 1.5% (95% CI 1.0-2.1). The results showed that the prevalence of echinococcosis in owned dogs, using copro-PCR assay was 42.6%. However, using conventional microscopy, 8% of fecal samples were positive for taeniid eggs. Our results suggest that regular treatment of the dog population with praziquantel every 60 days is ideal, however the frequency of dog dosing faces major logistics and cost challenges, threatening the sustainability of control programs. Understanding the nature and extent of dog reinfection in the endemic areas is essential for successful implementation of control programs and understanding patterns of CE transmission.

Identifying the Factors Affecting Methamphetamine Use: A Scoping Review.

Background: One of the critical factors affecting chronic diseases is the use of drugs, especially industrial substances, such as methamphetamine. Methamphetamine use is increasingly common among the younger members of society. Methamphetamine is not only physically and mentally destructive, but also has a significant impact on the families of abusers and society, and imposes a financial burden on society. The present study aims to identify the factors affecting methamphetamine use in a scoping review. Methods: Different keywords of methamphetamine were selected in the Mesh database and were searched in valid English databases from January 1, 2008, to April 5, 2022. Inclusion and exclusion criteria in this study were languages, reported findings, time range, and type of article. This study was designed by scoping review method developed by Askey Malley'O. Results: The total articles that were finally analyzed in this article were 42 including 12 English articles and 30 Persian articles. Among these articles, the most important factors affecting Methamphetamine are individual, social, and family factors, which have received the most cited. Conclusion: The majority of research highlights the importance of individual factors, society, and family factors, respectively, while formulating policies for prevention, treatment, and rehabilitation must be considered. It is suggested that structural path analysis be determined by prioritizing the identified factors and the weights of these components.

Comparing the association between heavy metals and cognitive status and depression in miners and non-miners: A study from southeast of Iran.

Heavy metal toxicity is a major public health crisis worldwide, especially in mining environments. The association between chronic heavy metals exposure and cognitive impairment has not been studied broadly in adults and mining fields. This study aimed to compare the association between arsenic (As), lead (Pb), and copper (Cu) concentration in blood and cognitive status and depression in copper miners and non-miners. Participants were selected from the Rafsanjan cohort study (RCS) as non-miners and miners from Sarcheshmeh Copper Complex. For evaluation of cognitive performance and creativity, comprehensive neurological tests were performed as follows: Mini-Mental Status Examination (MMSE), Paced Auditory Serial Addition Test (PASAT), Symbol Digit Modalities Test (SDMT), Psychomotor Vigilance Task (PVT), creativity tests including remote association task (RAT) and alternative uses task (AUT). Beck Depression Inventory-II was used to evaluate depression. Standard laboratory tests were also performed. Atomic absorption spectrophotometry was used to estimate the blood's concentration of As, Pb and Cu. We observed a significant difference between arsenic, lead, copper, and depression scores (all P < 0.001) in the two groups (miners and non-miners). Miners had a better performance in cognitive fields except in MMSE and PVT tests. Linear regression analyses showed that the lead had a negative association with the PVT test and depression score. The results suggest that the development of depression, cognitive impairments, and other health problems is possible in chronic heavy metal exposure, especially lead (Pb). Confirmation of our claim requires further study in the coming years.

What can death records tell us about multimorbidity?

BACKGROUND: Multimorbidity has been measured from many data sources which show that prevalence increases with age and is usually greater among women than men and in more recent periods. Analyses of multiple cause of death data have shown different patterns of multimorbidity associated with demographic and other characteristics. METHODS: Deaths in Australia among over 1.7 million decedents aged 55+ were stratified into three types: medically certified deaths, coroner-referred deaths with natural underlying causes and coroner-referred deaths with external underlying causes. Multimorbidity was measured by prevalence of ≥2 causes and analysed over three periods based on administrative changes: 2006-2012, 2013-2016 and 2017-2018. Poisson regression was used to examine the influence of gender, age and period. RESULTS: The prevalence of deaths with multimorbidity was 81.0% for medically certified deaths, 61.1% for coroner-referred deaths with natural underlying causes and 82.4% for coroner-referred deaths with external underlying causes. For medically certified deaths, multimorbidity increased with age: incidence rate ratio (IRR 1.070, 95% CI 1.068, 1.072) was lower for women than men (0.954, 95% CI 0.952, 0.956) and changed little over time. For coroner-referred deaths with natural underlying causes, multimorbidity showed the expected pattern increasing with age (1.066, 95% CI 1.062, 1.070) and being higher for women than men (1.025, 95% CI 1.015, 1.035) and in more recent periods. For coroner-referred deaths with external underlying causes, there were marked increases over time that differed by age group due to changes in coding processes. CONCLUSION: Death records can be used to examine multimorbidity in national populations but, like other data sources, how the data were collected and coded impacts the conclusions.

Prevalence of Domestic Violence against Women and Its Visibility in Southeast Iran.

Background: We aimed to estimate the prevalence of domestic violence against women at Reproductive Age (WARA) and its visibility in southeast of Iran. Methods: Adopting a modified time-location sampling, we recruited 933 WARA in the city of Kerman, Iran from Aug to Dec 2019. Domestic violence (DV) was divided into three main categories: Physical, psychological, and sexual. Data were obtained by direct and Network Scale-Up (NSU) methods through self-administered questionnaires. Generalized Estimating Equations (GEE) was used to determine the association between socioeconomic variables and the violence experience. Visibility was defined as the ratio of NSU over direct estimates. Results: Using the direct method, the annual prevalence of psychological violence was estimated at 60.9%. Corresponding figures for physical and sexual violence were 34.7% and 37.7%, respectively. NSU estimates were about one-third of the direct estimates. Divorced and widowed, self-employed, and less educated women were more likely to experience DV. Conclusion: While the average DV was as high as 44%, its visibility was as low as 33%. Nearly two-thirds of domestic violence against women remains undisclosed. This indicates a high level of stigma perceived around this type of violence.

A new data driven method for summarising multiple cause of death data.

BACKGROUND: National mortality statistics are based on a single underlying cause of death. This practice does not adequately represent the impact of the range of conditions experienced in an ageing population in which multimorbidity is common. METHODS: We propose a new method for weighting the percentages of deaths attributed to different causes that takes account of the patterns of associations among underlying and contributing causes of death. It is driven by the data and unlike previously proposed methods does not rely on arbitrary choices of weights which can over-emphasise the contribution of some causes of death. The method is illustrated using Australian mortality data for people aged 60 years or more. RESULTS: Compared to the usual method based only on the underlying cause of death the new method attributes higher percentages of deaths to conditions like diabetes and dementia that are frequently mentioned as contributing causes of death, rather than underlying causes, and lower percentages to conditions to which they are closely related such as ischaemic heart disease and cerebrovascular disease. For some causes, notably cancers, which are usually recorded as underlying causes with few if any contributing causes the new method produces similar percentages to the usual method. These different patterns among groups of related conditions are not apparent if arbitrary weights are used. CONCLUSION: The new method could be used by national statistical agencies to produce additional mortality tables to complement the current tables based only on underlying causes of death.

Estimated mortality due to seasonal influenza in southeast of Iran, 2006/2007 to 2011/2012 influenza seasons.

BACKGROUND: Global estimates showed an estimate of up to 650,000 seasonal influenza-associated respiratory deaths annually. However, the mortality rate of seasonal influenza is unknown for most countries in the WHO Eastern Mediterranean Region, including Iran. We aimed to estimate the excess mortality attributable to seasonal influenza in Kerman province, southeast Iran for the influenza seasons 2006/2007-2011/2012. METHODS: We applied a Serfling model to the weekly total pneumonia and influenza (PI) mortality rate during winter to define the epidemic periods and to the weekly age-specific PI, respiratory, circulatory, and all-cause deaths during non-epidemic periods to estimate baseline mortality. The excess mortality was calculated as the difference between observed and predicted mortality. Country estimates were obtained by multiplying the estimated annual excess death rates by the populations of Iran. RESULTS: We estimated an annual average excess of 40 PI, 100 respiratory, 94 circulatory, and 306 all-cause deaths attributable to seasonal influenza in Kerman; corresponding to annual rates of 1.4 (95% confidence interval [CI] 1.1-1.8) PI, 3.6 (95% CI 2.6-4.8) respiratory, 3.4 (95% CI 2.1-5.2) circulatory, and 11.0 (95% CI 7.3-15.6) all-cause deaths per 100,000 population. Adults ≥75 years accounted for 56% and 53% of all excess respiratory and circulatory deaths, respectively. At country level, we would expect an annual of 1119 PI to 8792 all-cause deaths attributable to seasonal influenza. CONCLUSIONS: Our findings help to define the mortality burden of seasonal influenza, most of which affects adults aged ≥75 years. This study supports influenza prevention and vaccination programs in older adults.

Population Size Estimation of People Who Use Illicit Drugs and Alcohol in Iran (2015-2016).

BACKGROUND: Estimating the number of people using illicit drugs and alcohol is necessary for informing health policy and programming. However, it is often challenging to reliably estimate the size of these marginalized populations through direct methods. In this study, we estimated the population size of these groups using the indirect Network Scale-Up (NSU) method in Iran from 2015 to 2016. METHODS: Using a self-administered questionnaire, we asked 15 124 individuals (54% men) about the number of people they know who used different types of drugs at least once in the past 12 months. Prevalence estimates were reported per 100 000 population. The uncertainty level (UL) was calculated using the bootstrap method. RESULTS: The average age of the respondents was 33 years old, and 35.1% of them were unmarried. The most common drugs and their prevalence were as follows: opium (2534 [95% UL: 2467-2598]), hashish (849 [95% UL: 811-886]), stimulants (methamphetamine, ecstasy pills, cocaine, and Ritalin) (842 [95% UL: 802-879]), heroin/crack (578 [95% UL: 550-607]), and drug injection (459 [95% UL: 438-484]). Additionally, we estimated the prevalence of alcohol use as 2797 (95% UL: 2731-2861). On average, substance use was 5.23 times more prevalent among men than women. Opium use was more prevalent among individuals aged >50 years old. Moreover, alcohol use was more prevalent among participants between 18 and 30 years old (5164 per 100 000 population). CONCLUSION: Although opium continues to be the most prevalent illicit drug in Iran, the patterns of illicit drug use are heterogeneous among different age groups, genders, and provinces. Age-gender specific and culturally appropriate interventions are warranted to meet the needs of people in different subgroups.

Estimating the Number of COVID-19 Cases and Impact of New COVID-19 Variants and Vaccination on the Population in Kerman, Iran: A Mathematical Modeling Study.

COVID-19 is spreading all over Iran, and Kerman is one of the most affected cities. We conducted this study to predict COVID-19-related deaths, hospitalization, and infected cases under different scenarios (scenarios A, B, and C) by 31 December 2021 in Kerman. We also aimed to assess the impact of new COVID-19 variants and vaccination on the total number of COVID-19 cases, deaths, and hospitalizations (scenarios D, E, and F) using the modified susceptible-exposed-infected-removed (SEIR) model. We calibrated the model using deaths reported from the start of the epidemic to August 30, 2021. A Monte Carlo Markov Chain (MCMC) uncertainty analysis was used to estimate 95% uncertainty intervals (UI). We also calculated the time-varying reproductive number (R t) following time-dependent methods. Under the worst-case scenario (scenario A; contact rate = 10, self-isolation rate = 30%, and average vaccination shots per day = 5,000), the total number of infections by December 31, 2021, would be 1,625,000 (95% UI: 1,112,000-1,898,000) with 6,700 deaths (95% UI: 5,200-8,700). With the presence of alpha and delta variants without vaccine (scenario D), the total number of infected cases and the death toll were estimated to be 957,000 (95% UI: 208,000-1,463,000) and 4,500 (95% UI: 1,500-7,000), respectively. If 70% of the population were vaccinated when the alpha variant was dominant (scenario E), the total number of infected cases and deaths would be 608,000 (95% UI: 122,000-743,000) and 2,700 (95% UI: 700-4,000), respectively. The R t was ≥1 almost every day during the epidemic. Our results suggest that policymakers should concentrate on improving vaccination and interventions, such as reducing social contacts, stricter limitations for gathering, public education to promote social distancing, incensing case finding and contact tracing, effective isolation, and quarantine to prevent more COVID-19 cases, hospitalizations, and deaths in Kerman.

Dynamic modeling of female neutering interventions for free-roaming dog population management in an urban setting of southeastern Iran.

Understanding dynamics of free-roaming dog (FRD) population is critical for planning and implementation of dog population management programs. FRD population size estimation as well as dynamic modeling of dog population under different female dog neutering interventions were investigated in order to determine the most appropriate animal birth control approach. We performed population size estimate of dogs using sight-resight surveys by photography in a randomly selected 25 blocks of the city and all the suburbs of greater Kerman area. Main demographic features were characterized and the dog density distribution was mapped. A dynamic model was developed to predict free-roaming dog population variations after 5 and 10 years. Different scenarios based on 10, 30, 50, 60 and 70% female dog sterilization were considered to predict the effects of animal birth control measures. Free roaming dog population was estimated at 6781 dogs (65.3% males) in Kerman and suburbs with several major population hotspots. Analysis of the dog locations within the city showed that the largest proportion of the dogs were observed in the vacant lots (46.2%). Modeling predictions indicated that, in the absence of management, the free-roaming dog population could increase from a baseline of 6781 to 13,665 dogs (2.02 fold increase) in 5 years and to 19,376 dogs in 10 years (2.86 fold increase). Using a population dynamics model, we simulated five neutering coverages to explore the impact of female neutering on free-roaming dog population size. The 5-year projections of the model have shown that 50% annual female dog sterilization significantly reduced free-roaming dog population by 0.44 comparing to the baseline population. Findings of the present study improve our knowledge on the nature and extent of dog population dynamics in Iran. Effective population control and selection of the most appropriate neutering interventions require a comprehensive knowledge of the characteristics and dynamics of FRD population.

Maternal factors associated with interbirth intervals in Australia: Results from a population-based longitudinal study.

BACKGROUND AND OBJECTIVE: Short and long intervals between successive births are associated with adverse birth outcomes, especially in low-income and middle-income countries, yet the birth intervals in high-income countries remain relatively understudied. The aim was to examine maternal factors associated with birth intervals in Australia. METHODS: The sample comprised 6130 participants in the Australian Longitudinal Study on Women's Health who were born in 1973-1978, had two or more births, and responded to regular surveys between 1996 and 2018. Interbirth interval (IBI) was defined as the time between successive live births. Maternal factors were examined using accelerated failure time models. RESULTS: For women with only two births (n = 3802), the median time to the second birth was 34.0 months (IQR 23.1, 46.2) with shorter IBI associated with higher socioeconomic status (eg, university education (31.9 months), less income stress (31.1)), and longer IBI associated with age over 35 (39.7), fair/poor health (43.0), untreated fertility problems (45.5), miscarriage (39.4), or abortion (41.0). For women with three or more births (n = 2328), the median times to the second and third births were 31.2 months (19.9, 42.1) and 36.5 months (25.3, 50.1), respectively; some factors were consistent between the first IBI and second IBI (eg, university education and being married were associated with shorter IBI), whereas income stress was associated with longer first IBI but not with second IBI. CONCLUSIONS: Understanding maternal factors associated with birth intervals in a high-income country like Australia may enable more nuanced tailoring of guidelines for prepregnancy care.

Iran to achieve the SDG 3.4 at national and sub-national levels.

The present study investigates different scenarios to project the chance of achieving SDG 3.4 in Iran. In this study, the Iranian Death Registry System data was employed to estimate the Unconditional Probability of Dying (UPoD) for the four major categories of NCDs; then, the Bayesian model averaging was used to project the UPoD at the national and sub-national levels. Also, the prevalence of the risk factors was projected by 2030 based on STEPs as well as some other study data. Plus, UPoD and the possibility of achieving the target were estimated once again based on the assumption that the global reduction in risk factors proposed by WHO would be adopted in Iran. The UPoDs for the four NCDs in Iran were 17.5% (95% UI: 16.3-19.2) and 14.7% (13.3-16.2) in 2010 and 2015 respectively and if the current trend continues, 2030 will mark the UPoD of 10.8% (7.9-14.3). However, If the risk factors are reduced to the WHO target level by 2030, the UPoDs will be reduced to 5.44% (3.51-7.39) and 6.55% (5.00-8.13) of the 2010 and 2015 baseline scenarios, respectively, to enable some provinces to meet SDG 3.4. If the current trend continues, Iran will and will not achieve the SDG 3.4 in 2010 and 2015 baseline scenarios, respectively. However, if the global target set for reducing risk factors is achieved, Iran will meet all expectations in SDG 3.4 except in Asthma and COPD. Therefore, effective interventions are recommended to be designed and followed to reduce Asthma and COPD.

Prevalence and 5-year incidence rate of dyslipidemia and its association with other coronary artery disease risk factors in Iran: Results of the Kerman coronary artery disease risk factors study (Phase 2).

BACKGROUND: Dyslipidemia (DL) is an important risk factor of coronary artery disease (CAD). We evaluated DL prevalence and its 5-year incidence rate in southeastern Iran, to assess the severity and growth rate of this CAD risk factor in the region. MATERIALS AND METHODS: This study was a part of the Kerman CAD Risk Factors Study Phase 2 (2014-2018) among 9996 individuals aged 15-80 years, from whom 2820 individuals had also participated in Phase 1 (2009-2011). In mg/dl, cholesterol ≥240 and/or low-density lipoprotein cholesterol ≥160 and/or high-density lipoprotein cholesterol <40 for men and <50 for women and/or triglyceride >200 were defined as DL. RESULTS: The lipid profile of 9911 persons was analyzed. Overall 19.6% had borderline cholesterol and 6.4% suffered from hypercholesterolemia. 56.6% of the population (62.5% of females vs. 48.5% of males) suffer from DL, from whom 73.4% were undiagnosed. Female gender, advanced age, obesity, hypertension, diabetes, anxiety, and depression predicted DL in the study population. The prevalence of DL was significantly lower in Phase 2 (56.6%) compared to Phase 1 (81.4%). The prevalence of undiagnosed DL (UDL) and diagnosed DL (DDL) was 40.7% and 16.2%, respectively. The 5-year incidence rate of DL was 2.58 persons/100 person-years (3.24 in females vs. 2.20 in males). CONCLUSION: Although there were promising signs of a reduction in DL and increase in DDL in the last 5 years, a high percentage of the population have DL yet, from whom mostly are undiagnosed. DL was significantly associated with other CAD risk factors. Therefore, the health-care management system should improve its strategies to reduce the health burden of DL.

Review of Size Estimation Methods.

Understanding and measuring the burden of HIV faces several remaining challenges around the globe. HIV prevention, care, and treatment efforts, including advocacy for populations at risk of HIV, the design and implementation of national guidelines, monitoring the coverage of HIV programs and evaluating their impact, are not feasible without relatively precise estimates of the impact and magnitude of HIV among different subpopulations.

Methods to Estimate the Average Social Network Size.

One of the requirements to calculate the size of a KP by the NSU method is to know the average social network size of the general population accurately (shown by C).

Estimating the Size of Hidden Groups.

NSU studies have been applied in different countries. For example, this technique has been used in the United States to estimate the number of women who had been raped in the last year.

Data Smoothing, Extrapolation, and Triangulation.

While population size data at the national and subnational levels are critical for planning and resource allocation, most PSE studies are conducted in a few selected cities and towns due to resource and time constraints. Extrapolation methods to estimate the population size for locations not included in the PSE exercise are critical to providing data for all subnational jurisdictions and the entire country as a whole. The decision on how to select cities or towns that reflect best the national picture is a critical first step. You may need to include cities or towns from areas with low, medium, or high prevalence of your target population(s). Having some data from all these (three) areas increase the power of your study and helps to better extrapolate the results to unobserved areas, and to the national level. Through this process, data smoothing of subnational data is often needed due to relatively small samples size problem. In this chapter, we describe methods that are required for smoothing subnational data, model subnational data to extrapolate estimates to regional and national levels, and triangulate findings from different size estimation methods by a Bayesian framework to produce credible estimates.

Short-term and long-term survival of patients with gastric cancer.

AIM: The aim of this study was to apply the Bayesian mixture cure rate frailty model to determine the factors that influence short-term and long-term survival of patients with gastric cancer. BACKGROUND: Determining the risk factors of gastric cancer is currently considered very important, because the disease has become one of the most dangerous types of mortal cancers. Therefore, it is possible to determine the effective risk factors of short-term and long-term survival in patients through utilizing this model. METHODS: The present retrospective study was conducted on 339 gastric cancer patients whose data was recorded in hospitals of Kerman province, Iran, during 2001-2015. In the study, the Bayesian mixture cure rate frailty model was used to determine the effective factors of short-term and long-term survival in patients. RESULTS: In the present study, the event of interest occurred for 57.5% of patients. Over time, the survival rate of cancer patients reached its lowest point, approximately 0.3 at the end of study. According to the results of the present study, variables of chemotherapy (ß=-0.35 (-0.75, -0.03) and OR=1.59 (1.08, 2.19)), morphology (ß =-0.98(-1.45, -0.48) and OR=2.99 (1.78, 4.17)), and metastasis (ß =0.42(0.10, 0.93) and OR=0.39(0.01, 0.84)) were identified as effective factors in short-term and long-term survival of patients. CONCLUSION: The effective factors of long-term and short-term survival can be identified by utilizing the Bayesian mixture cure rate frailty model, while it is impossible through conventional models of survival analysis. Chemotherapy, morphology, and metastasis are the most important effective factors of short-term and long-term survival in patients with gastric cancer.

Public Stigma Toward Female and Male Opium and Heroin Users. An Experimental Test of Attribution Theory and the Familiarity Hypothesis.

Drug abuse and addiction exist around the world. People addicted to drugs such as opium or heroin often encounter dehumanizing discriminatory behaviors and health-care systems that are reluctant to provide services. Experiencing discrimination often serves as a barrier to receiving help or finding a home or work. Therefore, it is important to better understand the mechanisms that lead to the stigmatization of drug addiction and who is more prone to stigmatizing behaviors. There is also a dearth of research on whether different patterns of stigma exist in men and women. Therefore, this study investigated factors affecting gender-specific stigmatization in the context of drug addiction. In our vignette study (NMensample = 320 and NWomensample = 320) in Iran, we experimentally varied signals and signaling events regarding a person with drug addiction (i.e., NVignettes = 32 per sample), based on Attribution Theory, before assessing stigmatizing cognitions (e.g., blameworthiness), affective responses (e.g., anger), and discriminatory inclinations (e.g., segregation) with the Attribution Questionnaire. We also tested assumptions from the Familiarity Hypothesis by assessing indicators of respondents' familiarity with drug addiction (e.g., knowledge about addiction). Results, for example, show higher stigma if the person used "harder" drugs, displayed aggressive behavior, or had a less controllable drug urge. Self-attributed knowledge about addiction or prior drug use increased some forms of stigma, but diminished others. These findings only partially converged between men and women. We suggest that anti-stigma initiatives should consider information about the stigmatized person, conditions of the addiction, and characteristics of stigmatizers.