Zero-inflated Negative Binomial Regression Models Research Articles

Increased Postoperative Opioid Consumption in the Presence of Co-administration of 5-HT3 Antagonists with Acetaminophen: A Hospital Registry Study.

Acetaminophen and 5-hydroxytryptamine-type-3 (5-HT3) receptor antagonists are administered as standard prophylaxes for postoperative pain, nausea, and vomiting. Preclinical studies however suggest that 5-HT3 antagonists may compromise acetaminophen's analgesic effect. This hospital registry study investigates whether 5-HT3 antagonists mitigate the analgesic effect of prophylactic acetaminophen in a perioperative setting. This study included 55,016 adult patients undergoing general anesthesia for ambulatory procedures at a tertiary healthcare center in Massachusetts, United States of America, from 2015 to 2022. Using binary exposure variables and a comprehensive selection of pre-planned patient- and procedure-related covariates for confounder control, we investigated whether intraoperative 5-HT3 antagonists affected the association between pre- or intraoperative acetaminophen and postoperative opioid consumption, gauged by opioid dose in mg oral morphine equivalents (OME) administered in the post-anesthesia care unit (PACU). A multivariable, zero-inflated negative binomial regression model was applied. 3,166 (5.8%) patients received only acetaminophen, 15,438 (28.1%) only 5-HT3 antagonists, 31,850 (57.9%) both drugs, and 4,562 (8.3%) neither drug. The median PACU opioid dose was 7.5 mg OME (interquartile range 7.5 to 14.3 mg OME) among 16,640/55,016 (30.3%) patients who received opioids and the average opioid dose was 3.2 mg OME across all patients (maximum cumulative dose: 20.4 mg OME). Acetaminophen administration was associated with a 5.5% (95%CI -9.6% to -1.4%;p=0.009; adjusted absolute difference -0.19 mg OME;95%CI -0.33 to -0.05;p=0.009) reduction in opioid consumption among patients who did not receive a 5-HT3 antagonist, while there was no effect in patients who received a 5-HT3 antagonist (adjusted absolute difference 0.00 mg OME; 95%CI -0.06 to 0.05;p=0.93,p-for-interaction=0.012). A dose-dependent association of pre- or intraoperative acetaminophen with decreased postoperative opioid consumption was not observed when 5-HT3 antagonists were co-administered, suggesting that physicians might consider reserving 5-HT3 antagonists as rescue medication for postoperative nausea or vomiting when acetaminophen is administered for pain prophylaxis.

Immigrant background, incarceration history and recidivism among adults assessed for illicit substance use severity: Findings from a Swedish registry study

BackgroundIn Sweden, as in other countries, individuals with immigrant backgrounds are disproportionately represented within the incarcerated population. This study examined the association between immigrant background and future incarceration for individuals assessed for illicit substance use severity, while considering their prior incarceration history. MethodsUsing data from Swedish Addiction Severity Index (ASI) assessments linked to register data from Statistics Sweden, we employed Zero-Inflated Negative Binomial (ZINB) regression models to analyse differences in incarceration histories within five years before and after ASI assessments based on immigrant backgrounds. Additionally, Cox proportional-hazard models were used to assess the likelihood of post-assessment incarceration among these groups. ResultsImmigrant background was positively associated with pre- and post-assessment incarceration. First- and second-generation immigrants from the Global South had longer periods of incarceration in the five years before assessments compared to native Swedes. Post-assessment, first-generation immigrants showed longer periods of incarceration. Survival analyses supported these findings, indicating a higher risk of prolonged post-assessment incarceration among all immigrant groups, particularly first-generation immigrants from the Global South. ConclusionAmong individuals assessed for illicit drug use within Swedish municipalities, those with immigrant backgrounds faced higher incarceration risks, even after controlling for substance use severity and prior incarceration. Tailored interventions and support systems are vital to prevent re-entry into the criminal justice system. Timely actions can break re-offending cycles, redirecting paths away from reoffending and towards legal reintegration, thereby reducing incarceration and recidivism rates.

Health Care Utilization and Direct Costs Prior to Subspecialty Care in Children with Chronic Pain Compared with Other Chronic Childhood Diseases: A Cohort Study

ObjectivesTo understand the burden associated with pediatric chronic pain (CP) on the healthcare system compared with other costly chronic diseases prior to subspecialty care. Study designIn this retrospective cohort study, we assessed all-cause healthcare utilization and direct healthcare costs associated with pediatric CP (n=91) compared with juvenile-onset arthritis (JA, n=135), inflammatory bowel disease (IBD, n=90), type 1 or type 2 diabetes (T1D, n=475, T2D, n=289), anxiety (n=7,193) and controls (n=273) two and five years prior to patients entering subspecialty care in Manitoba, Canada. Linked data from physician encounters, emergency department visits, hospitalizations, and prescriptions were extracted from administrative databases. Differences in healthcare utilization and direct healthcare costs associated with CP versus the other conditions were tested using negative binomial and zero-inflated negative binomial regression models, respectively. ResultsAfter adjustment for age at diagnosis, sex, location of residence, and socioeconomic status, CP continued to be associated with the highest number of consulted physicians and subspecialists and the highest number of physician billings compared with all other conditions (p<0.01, respectively). CP was significantly associated with higher physician costs than JA, IBD, T1D, T2D, or controls (p<0.01, respectively); anxiety was associated with the highest physician and prescription costs among all cohorts (p<0.01, respectively). ConclusionCompared with chronic inflammatory and endocrinologic conditions, pediatric CP and anxiety were associated with substantial burden on the healthcare system prior to subspecialty care, suggesting a need to assess gaps and resources in the management of CP and mental health conditions in the primary care setting.

Association of Acute Respiratory Disease Events with Quantitative Interstitial Abnormality Progression at CT in Individuals with a History of Smoking.

Background Acute respiratory disease (ARD) events are often thought to be airway-disease related, but some may be related to quantitative interstitial abnormalities (QIAs), which are subtle parenchymal abnormalities on CT scans associated with morbidity and mortality in individuals with a smoking history. Purpose To determine whether QIA progression at CT is associated with ARD and severe ARD events in individuals with a history of smoking. Materials and Methods This secondary analysis of a prospective study included individuals with a 10 pack-years or greater smoking history recruited from multiple centers between November 2007 and July 2017. QIA progression was assessed between baseline (visit 1) and 5-year follow-up (visit 2) chest CT scans. Episodes of ARD were defined as increased cough or dyspnea lasting 48 hours and requiring antibiotics or corticosteroids, whereas severe ARD episodes were those requiring an emergency room visit or hospitalization. Episodes were recorded via questionnaires completed every 3 to 6 months. Multivariable logistic regression and zero-inflated negative binomial regression models adjusted for comorbidities (eg, emphysema, small airway disease) were used to assess the association between QIA progression and episodes between visits 1 and 2 (intercurrent) and after visit 2 (subsequent). Results A total of 3972 participants (mean age at baseline, 60.7 years ± 8.6 [SD]; 2120 [53.4%] women) were included. Annual percentage QIA progression was associated with increased odds of one or more intercurrent (odds ratio [OR] = 1.29 [95% CI: 1.06, 1.56]; P = .01) and subsequent (OR = 1.26 [95% CI: 1.05, 1.52]; P = .02) severe ARD events. Participants in the highest quartile of QIA progression (≥1.2%) had more frequent intercurrent ARD (incidence rate ratio [IRR] = 1.46 [95% CI: 1.14, 1.86]; P = .003) and severe ARD (IRR = 1.79 [95% CI: 1.18, 2.73]; P = .006) events than those in the lowest quartile (≤-1.7%). Conclusion QIA progression was independently associated with higher odds of severe ARD events during and after radiographic progression, with higher frequency of intercurrent severe events in those with faster progression. Clinical trial registration no. NCT00608764 © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Little in this issue.

The Moderating Role of Collectivism on Physical Activity and Family Support: A Cross-Sectional Design.

An important value among Korean Americans is collectivism or giving a group priority over the individual. This value, family support, and demographic characteristics have been reported to influence health behaviors among this group. Yet, no study has examined how collectivism, family support, and demographic characteristics interact with each other and then influence physical activity among Korean American adults. The purpose of the study was to examine the association between family support and physical activity, and the moderating role of demographic characteristics and collectivism on this association among Korean American adults. A descriptive, cross-sectional study was conducted with a sample of 110 Korean American adults 18 years and older, residing in a Southwestern city in the United States. Self-administered questionnaires were used to measure demographics, collectivism, family support, and physical activity. Data analysis using a zero-inflated negative binomial regression model revealed a positive relationship between family support and physical activity, while age and gender were moderators of the relationship between family support and physical activity. Collectivism was positively related to physical activity and moderated the relationship between family support and physical activity. These findings indicate the significance of collectivism and family support that influence Korean American adults' physical activity.

Healthcare utilization and its association with socioeconomic status in China: Evidence from the 2011-2018 China Health and Retirement Longitudinal Study.

Healthcare utilization often favors the higher-socioeconomic status (SES) and having chronic diseases may exacerbate this inequality. This study aims to examine the trends in health service use over time, the effect of SES on healthcare utilization, and the role of chronic diseases in this association. Data used in this study were from the China Health and Retirement Longitudinal Study (CHARLS) in 2011, 2013, 2015, and 2018, which is the first nationally representative survey of the middle-aged and older. The sample included people aged 45 years and older who responded to all the waves. A total of 10,922 adults were included in this study. Healthcare utilization was categorized into outpatient and inpatient service use and SES was measured by per-capita household expenditure. A multilevel zero-inflated negative binomial regression model was performed to analyze outpatient and inpatient service use, separately. The rates of outpatient service use in 2011, 2013, 2015, and 2018 were 19.11%, 21.45%, 20.12%, and 16.32%, respectively, while the rates of inpatient service use were 8.40%, 13.04%, 14.17%, and 18.79%, respectively. Compared to individuals in the lowest quintile of per-capita household expenditure, those in higher quintiles had higher odds of outpatient service use (Q2: odds ratio = 1.233, p < 0.0001; Q3: 1.416, p < 0.0001; Q4: 1.408, p < 0.0001; or Q5: 1.439, p < 0.0001) and higher rates of inpatient service use (Q2: incidence rate ratio = 1.273, p < 0.0001; Q3: 1.773, p < 0.0001; Q4: 2.071, p < 0.0001; or Q5: 1.992, p < 0.0001). Additionally, having morbidity generally increased healthcare utilization, but did not play a significant role in moderating the relationship between SES and healthcare utilization. Healthcare utilization rates were overall low in China, but relatively high for people in higher quintiles of per-capita household expenditure or those with morbidity, compared to their counterparts. Policy actions are required to provide more health education to the public, to further optimize health insurance schemes targeting outpatient services, especially for the low-SES, and to establish new health delivery models for NCD management in the primary health care setting.

Modeling clustered count data using mixed effect discrete Weibull regression model with cubic splines

This paper investigates the use of mixed-effect discrete Weibull (DW) regression model with cubic splines for clustered count data. DW regression model can be used for both over and under-dispersed data thus, it can be an appropriate choice for researchers to use without having the risk to violate assumptions for using a particular model distribution. We used a cubic spline function to model the non-linear relationship between the outcome variable and the covariate. The proposed model is applied to a clustered dataset from the eighth Korean National Health and Nutrition Examination Survey (KNHANES VIII) from 2019 to assess the factors influencing the amount of alcohol drink in 17 different regions. We compared the results with our proposed model with those of Poisson, negative binomial, zero-inflated Poisson and zero-inflated negative binomial regression models in the presence of spline function. The results show that using DW regression model with cubic spline gives the best fit. We also held a simulation study to investigate the performance and the robustness of DW with a spline function. It turns out that DW regression model with a spline function can flexibly model clustered count data with various dispersion and data with many zeros.

Factors Influencing Time to Return to Learn Among NCAA Student-Athletes Enrolled in the Concussion Assessment, Research, and Education (CARE) Study.

The aim was to describe the demographic and post-injury factors that influence time to return to learn (RTL) among student-athletes enrolled in the Concussion Assessment, Research and Education (CARE) Consortium. A total of 47,860 student-athletes enrolled in the National Collegiate Athletic Association-Department of Defense (NCAA-DoD) CARE Consortium study from 2014 to 2020, with 1485 sport-related concussions (SRCs) analyzed in the present dataset. Demographic and post-injury characteristics were calculated using descriptive statistics, followed by Kaplan-Meier estimates to examine median time to return to normal academic performance (i.e., RTL) by sex (male, female), baseline psychiatric conditions (depression, anxiety) and/or learning disorder, NCAA division (I, II, III), SRC history (0, 1, 2, 3+), NCAA sport category (contact, limited contact, non-contact sport), and median difference in baseline/post-injury symptom severity scores (< 21, ≥ 21). Further, a multivariable zero-inflated negative binomial (ZINB) regression model was used to examine their association with RTL. Overall, time to RTL (mean = 4.96 ± 8.24days, median = 3.0 [interquartile range = 0.0, 6.0] days) was found to be influenced by several factors resulting in earlier trajectories. Notably, nearly 25% of the sample demonstrated immediate RTL (i.e., 0days). Among student-athletes who did not immediately RTL, males demonstrated a decreased rate in RTL (rate = 0.79; 95% CI 0.66-0.96) compared to females. Further, student-athletes with a ≥ 21 change in symptom severity score (post-injury baseline) demonstrated a higher rate of RTL (rate = 1.47; 95% CI 1.21-1.79) compared to student-athletes with a symptom severity change score < 21. Lastly, male student-athletes demonstrated two times higher odds (odds ratio = 1.95; 95% CI 1.02-3.73) of immediate RTL compared to female student-athletes. No other covariates were associated with time to RTL. Collectively, the present findings suggest a rapid return to the classroom following concussion. Specifically, males demonstrated higher odds of time to RTL, whereas those with greater differences in symptom severity resulted in a higher rate of time to RTL among those who did not immediately RTL. Ultimately, these findings support prior work emphasizing an individualized approach to SRC management.

Geospatial investigations in Colombia reveal variations in the distribution of mood and psychotic disorders

BackgroundGeographical variations in mood and psychotic disorders have been found in upper-income countries. We looked for geographic variation in these disorders in Colombia, a middle-income country. We analyzed electronic health records from the Clínica San Juan de Dios Manizales (CSJDM), which provides comprehensive mental healthcare for the one million inhabitants of Caldas.MethodsWe constructed a friction surface map of Caldas and used it to calculate the travel-time to the CSJDM for 16,295 patients who had received an initial diagnosis of mood or psychotic disorder. Using a zero-inflated negative binomial regression model, we determined the relationship between travel-time and incidence, stratified by disease severity. We employed spatial scan statistics to look for patient clusters.ResultsWe show that travel-times (for driving) to the CSJDM are less than 1 h for ~50% of the population and more than 4 h for ~10%. We find a distance-decay relationship for outpatients, but not for inpatients: for every hour increase in travel-time, the number of expected outpatient cases decreases by 20% (RR = 0.80, 95% confidence interval [0.71, 0.89], p = 5.67E-05). We find nine clusters/hotspots of inpatients.ConclusionsOur results reveal inequities in access to healthcare: many individuals requiring only outpatient treatment may live too far from the CSJDM to access healthcare. Targeting of resources to comprehensively identify severely ill individuals living in the observed hotspots could further address treatment inequities and enable investigations to determine factors generating these hotspots.

Lack of Association between Antimicrobial Consumption and Antimicrobial Resistance in a HIV Preexposure Prophylaxis Population: A Cross-Sectional Study.

In antibiotic naïve populations, there is a strong association between the use of an antimicrobial and resistance to this antimicrobial. Less evidence is available as to whether this relationship is weakened in populations highly exposed to antimicrobials. Individuals taking HIV preexposure prophylaxis (PrEP) have a high intake of antimicrobials. We previously found that there was no difference in the prevalence of pheno- and genotypic antimicrobial resistance between two groups of PrEP clients who had, and had not, taken antimicrobials in the prior 6 months. Both groups did, however, have a higher prevalence of resistance than a sample of the general population. In the current study, we used zero-inflated negative binomial regression models to evaluate if there was an individual level association between the consumption of antimicrobials and 1. the minimum inhibitory susceptibilities of oral Neisseria subflava and 2. the abundance of antimicrobial resistance genes in the oropharynges of these individuals. We found no evidence of an association between the consumption of antimicrobials and the minimum inhibitory susceptibilities of oral Neisseria subflava or the abundance of antimicrobial resistance genes in these individuals. We conclude that in high-antimicrobial-consumption populations, the association between antimicrobial consumption and resistance may be attenuated. This conclusion would not apply to lower-consumption populations.

A study on the relationship between social value orientation and giving behavior: Application of the zero-inflated negative binomial regression model

This study was conducted to examine the effect of an individual's level of social value orientation on giving behavior. For this analysis, data was collected from the Korea Philanthropy Education Forum among Korean adults(n=1,037). Social value orientation was categorized according to Deutsch(1958) as the pursuit of communal benefits, the pursuit of equality of outcomes, and the valuation of others and society. The influence of these value levels on volunteer participation behavior was observed. The zero-inflated negative binomial regression model, which estimates two regression equations simultaneously based on the distribution of the dependent variable, was employed as the analysis method.&#x0D; According to the zero-inflated model analysis, those who pursued equality in outcomes were more likely to belong to the group that did not participate in volunteering. On the other hand, those who pursued valuation of others and society were more likely to belong to the group that engaged in volunteering. Based on the negative binomial model estimation, as the pursuit of equality of outcomes and the pursuit of valuation of others and society increased, the annual volunteer activity time was significantly higher.&#x0D; This study holds significance in that it empirically analyzes the influence of social value orientation on actual giving behavior among the general public by applying the zero-inflated negative binomial regression model.

ZERO-INFLATED NEGATIVE BINOMIAL MODELING IN INFANT DEATH CASE DUE TO PNEUMONIA IN EAST JAVA PROVINCE

Pneumonia is an acute infectious disease of the respiratory tract and an infection caused by a virus, bacteria or fungus that attacks the lung tissue. Several cases of pneumonia have resulted in deaths that occurred in toddlers aged 12-59 months. Based on official health in profile data, East Java's health in 2021 has a zero number of deaths under five aged 12-59 months due to pneumonia. Modeling data with many response variables is zero and there is overdispersion can be done using Zero Inflated Negative Binomial (ZINB) regression. This study aims to model the number of infant deaths aged 12-59 months due to pneumonia in East Java Province based on seven factors that are considered to influence the number of deaths in infants due to pneumonia. From this model, it can be seen that the factors that significantly influence the death of infants aged 12-59 months due to pneumonia in East Java Province using Zero Inflated Negative Binomial (ZINB) regression. The results of testing the parameters of the ZINB regression model show that the predictor variables that have a partial significant effect on the negative binomial model in East Java are the percentage of infants who received complete basic immunization, the percentage of coverage of under-five health services, the percentage of under-five children with malnutrition, the percentage of LBW (low birth weight babies). Selection of the best model is obtained by using the Bayesian Information Criterion (BIC) of 101,587.

Analyzing Freeway Safety Influencing Factors Using the CatBoost Model and Interpretable Machine-Learning Framework, SHAP

Exploring and analyzing safety influencing factors can guide targeted traffic safety management. Traditional traffic safety models are aimed at specific data problems and making adjustments to the model structure, which lack focus on predictive ability and have limited information on the analysis of influencing factors. In recent years, machine-learning methods have opened new avenues in modeling that have higher prediction accuracy, can identify complex nonlinear relationships, and can overcome over- and under-dispersion and correlation. Machine-learning methods, however, pose the problem of limited interpretability. The interpretable machine-learning framework SHAP can be an effective solution, which can not only reflect the influence of features in each sample but also generate global interpretation. This study established gradient boosting models including the CatBoost and XGBoost models as traffic safety models, which were compared with a traditional NB regression model and a zero-inflated negative binomial regression model. SHAP was used to analyze several safety influencing factors, including geometric design features, traffic operation characteristics, time of day, and land use. Results confirmed that the CatBoost model has better prediction ability and is a more suitable traffic safety model than the traditional negative binomial regression model. Among the key findings were that ramp type is the most important factor in freeway crash frequency; curve presence has a great positive impact, while truck proportion has a great negative impact; and traffic volume is highly correlated with truck proportion. These findings can provide theoretical support for safety operation management and targeted improvement measures for freeways.

Factors Influencing Adolescent Generalized Anxiety Disorder: A Zero-Inflated Negative Binomial Regression Model.

The current study used secondary data from the 17th Korea Youth Risk Behavior Survey conducted in 2021 to identify risk factors influencing the frequency with which adolescents in Korea experience generalized anxiety. Participants were 54,848 adolescents. Risk factors for generalized anxiety were analyzed using a zero-inflated negative binomial regression model. Of participants, 23.7% reported no generalized anxiety experiences. Risk factors identified in the count model were being female and having low household economic status as well as perceived stress, sadness, subjective sleep insufficiency, and loneliness. In the logit model, being female, in middle school, having middle and low household economic status, not living with family, having perceived stress, sadness, suicidal ideation, subjective sleep insufficiency, loneliness, and body image distortion were significant predictors of future anxiety among participants without anxiety. These results may be useful for planning nursing interventions to improve and prevent future health problems in adolescents. [Journal of Psychosocial Nursing and Mental Health Services, xx(x), xx-xx.].

Geographically Weighted Zero-Inflated Negative Binomial Regression: A general case for count data

Poisson and Negative Binomial Regression Models are often used to describe the relationship between a count dependent variable and a set of independent variables. However, these models fail to analyze data with an excess of zeros, being Zero-Inflated Poisson (ZIP) and Zero-Inflated Negative Binomial (ZINB) models the most appropriate to fit this kind of data. To Incorporate the spatial dimension into the count data models, Geographically Weighted Poisson Regression (GWPR), Geographically Weighted Negative Binomial Regression (GWNBR) and Geographically Weighted Zero-Inflated Poisson Regression (GWZIPR) have been developed, but the zero-inflation part of the negative binomial distribution is undeveloped in order to incorporate the overdispersion and the excess of zeros, as was at the beginning of the COVID-19 pandemic, whereas some places were having an outbreak of cases and in others places, there were no cases yet. Therefore, we propose a Geographically Weighted Zero-Inflated Negative Binomial Regression (GWZINBR) model which can be considered a general case for count data, since locally it can become a GWZIPR, GWNBR or a GWPR model. We applied this model to simulated data and to the cases of COVID-19 in South Korea at the beginning of the pandemic in 2020 and the results showed a better understanding of the phenomenon compared to the GWNBR model.

Analysis of the Effects of Highway Geometric Design Features on the Frequency of Truck-Involved Rear-End Crashes Using the Random Effect Zero-Inflated Negative Binomial Regression Model

Statistical data indicate that trucks are more prone to rear-end crashes, making this an area of concern. The objective of this study is to create a model that analyzes the factors influencing the frequency of rear-end crashes involving trucks (TIRC). To achieve this, researchers identified the most appropriate model as Spatial Zero-Inflated Negative Binomial Regression (SZINB). This model takes into account spatial correlation, which plays a significant role in the occurrences of TIRC on different road segments supervised by each highway ward. The estimation of parameters in the SZINB model has led to key findings that shed light on the factors contributing to a higher likelihood of TIRC. These findings include the increased probability of TIRC on curved roads compared to straight ones, roads that feature open middle islands, six lanes per direction, a slope, right-of-way shoulder width, pavement type, lane width, and a post speed limit. Based on these key findings, this study developed policy recommendations and sample measures aimed at reducing the frequency of TIRC. Implementing measures such as improving the road design on curved sections, optimizing middle islands, and enhancing traffic management on wider roads can help mitigate the risk of crashes involving trucks.

Risk Factors for Chronic Obstructive Pulmonary Disease Exacerbations among Individuals without a History of Recent Exacerbations: A COPDGene Analysis.

Rationale: Acute exacerbations of chronic obstructive pulmonary disease (AE-COPD) are detrimental events in the natural history of COPD, but the risk factors associated with future exacerbations in the absence of a history of recent exacerbations are not fully understood. Objectives: To identify risk factors for COPD exacerbations among participants in the Genetic Epidemiology of COPD Study (COPDGene) without a history of exacerbation in the previous year. Methods: We identified participants with a smoking history enrolled in COPDGene who had COPD (defined as forced expiratory volume in 1 second [FEV1]/forced vital capacity < 0.70), no exacerbation in the year before their second study site visit, and who completed at least one longitudinal follow-up questionnaire in the following 36 months. We used univariable and multivariable zero-inflated negative binomial regression models to identify risk factors associated with increased rates of exacerbation. Each risk factor's regression coefficient (β) was rounded to the nearest 0.25 and incorporated into a graduated risk score. Results: Among the 1,528 participants with a smoking history and COPD enrolled in COPDGene without exacerbation in the year before their second study site visit, 508 participants (33.2%) had at least one moderate or severe exacerbation in the 36 months studied. Gastroesophageal reflux disease, chronic bronchitis, high symptom burden (as measured by Modified Medical Research Council Dyspnea Scale and COPD Assessment Test), and lower FEV1% predicted were associated with an increased risk of exacerbation. Each 1-point increase in our graduated risk score was associated with a 25-30% increase in exacerbation rate in the 36 months studied. Conclusions: In patients with COPD without a recent history of exacerbations, gastroesophageal reflux disease, chronic bronchitis, high symptom burden, and lower lung function are associated with increased risk of future exacerbation using a simple risk score that can be used in clinical practice.

Discounting of Hyper-Palatable Food and Money: Associations with Food Addiction Symptoms.

Delay discounting (DD), the tendency to prefer small, immediate rewards over larger, delayed rewards, is associated with health-risk behaviors. The study examined associations between DD for money and hyper-palatable foods (HPF) with food addiction (FA) symptoms among a general population sample. Participants (N = 296) completed an adjusting DD task that consisted of a single-commodity condition with HPF as the reward (HPF now vs. HPF later) and cross-commodity conditions comparing money and HPF (money now vs. HPF later; HPF now vs. money later). The Yale Food Addiction Scale 2.0 was used to assess FA symptoms. Zero-inflated negative binomial regression models tested whether discounting of HPF and money was associated with FA symptoms. Findings indicated there were no significant associations between DD and FA symptoms in the single-commodity HPF condition (logit: OR = 1.02, p-value = 0.650; count: IRR = 1.04, p-value = 0.515). There were no significant associations among cross-commodity conditions comparing money now vs. HPF later (logit: OR = 0.96, p-value = 0.330; count: IRR = 1.02, p-value = 0.729) or conditions comparing HPF now vs. money later (logit: OR = 1.02, p-value = 0.682; count: IRR = 0.92, p-value = 0.128) and FA symptoms. Discounting HPF may not be a key behavioral feature among individuals who endorse FA symptoms.

Dealing with Zeros: Adolescent Drug Use, Perceived Disapproval, and Perceived Harm

Because studies examining youth drug use often have data with a high proportion of zeros, they often do not meet the assumptions for univariate or linear regression analyses that are typically used. We demonstrate the use of zero-inflated negative binomial regression models to address excessive zeros in drug use frequency on perceptions of disapproval and perceived harm among middle and high school students ( N = 522). We found that perceptions of parent disapproval were a better predictor of marijuana use ( p = .01) than peer disapproval. Perceived harm was related to marijuana use ( p = .04). Researchers should consider using zero-inflated negative binomial regression models when examining youth drug use.

Effectiveness of BNT162b2 and Sinovac vaccines against the transmission of SARS-CoV-2 during Omicron-predominance in Hong Kong: A retrospective cohort study of COVID-19 cases.

In 2022, SARS-CoV-2 Omicron variants circulated globally, generating concerns about increased transmissibility and immune escape. Hong Kong, having an infection-naive population with a moderate 2-dose vaccine coverage (63% by the end of 2021), experienced a COVID-19 epidemic largely seeded by Omicron BA.2 variants that led to the greatest outbreak in the region to date. Little remains known about the protection of commonly-administered vaccines against transmission of Omicron BA.2 variants. In this retrospective cohort study, we identified 17 535 laboratory-confirmed COVID-19 cases using contact tracing information during the Omicron-predominant period between January and June 2022 in Hong Kong. Demographic characteristics, time from positive test result to case reporting, isolation, or hospital admission, as well as contact tracing history and contact setting were extracted. Transmission pairs were reconstructed through suspected epidemiological links according to contact tracing history, and the number of secondary cases was determined for each index case as a measurement for risk of transmission. The effectiveness of mRNA vaccine (BNT162b2) and inactivated vaccine (Sinovac) against transmission of BA.2 variants was estimated using zero-inflated negative binomial regression models. Vaccine effectiveness against transmission for patients who received the 2-dose BNT162b2 vaccine was estimated at 56.2% (95% CI: 14.5, 77.6), 30.6% (95% CI: 13.0, 44.6), and 21.3% (95% CI: 2.9, 36.2) on 15 - 90, 91 - 180, and 181 - 270 days after vaccination, respectively, showing a significant decrease over time. For 3-dose vaccines, vaccine effectiveness estimates were 41.0% (95% CI: 11.3, 60.7) and 41.9% (95% CI: 6.1, 64.0) on 15 - 180 days after booster doses of Sinovac and BNT162b2, respectively. Although significant vaccine effectiveness was detected in household settings, no evidence of such protective association was detected in non-household settings for either Sinovac or BNT162b2. Moderate and significant protection against Omicron BA.2 variants' transmission was found for 2 and 3 doses of Sinovac or BNT162b2 vaccines. Although protection by 2-dose BNT162b2 may evidently wane with time, protection could be restored by the booster dose. Here, we highlight the importance of continuously evaluating vaccine effectiveness against transmission for emerging SARS-CoV-2 variants.