Semiparametric regression methods for temporal processes subject to multiple sources of censoring

Process regression methodology is underdeveloped relative to the frequency with which pertinent data arise. In this article, the response-190 is a binary indicator process representing the joint event of being alive and remaining in a specific state. The process is indexed by time (e.g., time since diagnosis) and observed continuously. Data of this sort occur frequently in the study of chronic disease. A general area of application involves a recurrent event with non-negligible duration (e.g., hospitalization and associated length of hospital stay) and subject to a terminating event (e.g., death). We propose a semiparametric multiplicative model for the process version of the probability of being alive and in the (transient) state of interest. Under the proposed methods, the regression parameter is estimated through a procedure that does not require estimating the baseline probability. Unlike the majority of process regression methods, the proposed methods accommodate multiple sources of censoring. In particular, we derive a computationally convenient variant of inverse probability of censoring weighting based on the additive hazards model. We show that the regression parameter estimator is asymptotically normal, and that the baseline probability function estimator converges to a Gaussian process. Simulations demonstrate that our estimators have good finite sample performance. We apply our method to national end-stage liver disease data. The Canadian Journal of Statistics 48: 222–237; 2020 © 2019 Statistical Society of Canada     

Workplace aggression against health care workers,law enforcement officials,and bus drivers: Differences in prevalence,perceptions, and psychological consequences

Investigations into workplace aggression (WPA) remain largely occupation specific, with few studies using a comparative approach. The aim of the present study was to compare the health care, law enforcement, and public transportation sectors with regards to the prevalence of different types of WPA, the perceptions of workers toward WPA, and the psychological consequences of such acts. A cross-sectional survey was completed by 1,774 workers in Canada. Multinomial regressions were utilized to address the objectives. Findings revealed that verbal abuse victimization was particularly common in bus drivers, witnessing death threats was most frequent among law enforcement officials, and witnessing all types of WPA was most common among health care workers. Although bus drivers did not normalize WPA, they feared complaining about violence to their employer and thought it useless to talk it about unless wounds were visible. Fear of complaining about violence to colleagues was prevalent in health care and law enforcement, both sectors in which WPA was normalized. Finally, flashbacks and irritability following WPA were most likely to affect bus drivers whereas health care workers experienced hypervigilance to a greater extent. Strategies to tailor primary, secondary, and tertiary prevention according to these distinctions are suggested to offer a better-informed response to WPA.     

Prevalence of low bone health using quantitative ultrasound in Indian women aged 41–60 years: Its association with nutrition and other related risk factors

The purpose of this study was to find the prevalence of low bone health conditions and assess associated nutritional and other risk factors in Indian women aged 41–60 years. A total of 1,911 women participated in this cross-sectional study. Bone health was assessed using an Omnisense multisite quantitative ultrasound bone densitometer on two sites (radius and tibia). Crude prevalence of osteopenia and osteoporosis was found to be 30.09% and 19.89%, respectively. The Indian women were deficient in a majority of nutrients. Postmenopause, hysterectomy, hyperthyroid, hypothyroid, hypertension, low physical activity, low sun exposure, high stress levels, and low calcium levels were found to be independent risk factors of low bone health.     

糖调节异常者甲状腺功能的研究

目的调查糖调节异常者合并甲状腺功能异常的患病率,并探讨其危险因素。方法选取青岛市城阳区人民医院内分泌门诊就诊者902例为研究对象,年龄为(18～78)岁。通过葡萄糖耐量试验(OGTT)分别确定糖耐量异常(IGT)、空腹血糖受损(IFG)、空腹血糖受损合并糖耐量异常(IFG+IGT)及正常糖耐量(NGT)等4组。通过固相化学发光免疫分析检测患者甲状腺功能,并作统计学处理。结果①IFG甲状腺功能异常率为11.6%,IGT异常率为11.7%,IFG+IGT异常率为18.6%,高于NGT的6.8%(P0.01)。②IFG甲状腺功能亢进症的患病率明显高于甲状腺功能减退症(P0.05);IGT甲状功能减退患病率明显高于甲状腺功能亢进(P0.05);IFG+IGT甲状功能减退症患病率明显高于甲状腺功能亢进症(P0.01)。以上三组均女性高于男性,差异有统计学意义(P0.01或P0.05)。③年龄、性别、空腹胰岛素(InFINS)为IFG合并甲亢的危险因素,年龄、性别为IGT、IFG+IGT合并甲减的危险因素,InFINS、负荷后30分钟胰岛素(In30INS)为其保护因素。结论①糖调节异常易于合并甲状腺功能异常,尤其是合并甲状腺功能减退,且IFG+IGT合并甲状腺功能异常率最高,为18.6%。②性别、年龄、胰岛素是导致糖调节异常者甲状腺功能异常的重要影响因素。     

Prevalence Rates of Youth Gambling Problems: Are the Current Rates Inflated?

While there is a general consensus in the literature that it is common for youth to gamble, considerable variability in the reported prevalence rates of youth problem gambling has been found. More recently, issues concerning the possible overestimation of these rates have been raised. Arguments underlying the proposition that problem gambling rates for youth are inflated are examined. It is acknowledged that more rigorous research is required, including the need for the development and refinement of current adolescent instruments and screening tools, agreement upon a gold standard criterion for adolescent problem gambling, and clarity of nomenclature issues. The advancement of scientific knowledge concerning the underlying risk factors associated with the onset and course of youth gambling involvement and the role of effective adolescent prevention and treatment programs will require these fundamental research questions to be addressed.     

Estimating the Prevalence of Illegal Drug Use

A generic globally applicable integral equation allows the estimation of hidden drug use. Formulas for estimating the prevalence of drug use are provided for both the assumed and known latency period. Estimates of prevalence of opiate use in Ireland ranging from 7,955 [5,789, 10,122] to 11,986 [8,792, 15,181] with prevalence rates ranging from 2.7 [2.0, 3.5] per 1,000 to 4.1 [3.0, 5.2] were obtained. The model can be implemented by service providers and planners if numbers of first treatments for drug use and the latency period are known or assumed.     

Increased prevalence of premature ejaculation in men with metabolic syndrome

This prospective study aimed to investigate the relationship between metabolic syndrome (Met S) and premature ejaculation (PE) among men. The study included 300 consecutive male patients (53.6 y?±?8.7) who attended the urology clinic (December 2013–September 2014), mostly complaining of renal/ureteric calculi. A diagnostic approach was undertaken to include demographics, clinical features and laboratory investigations of the study subjects. Both erectile function and PE were evaluated using the International Index of Erectile Function (abridged form, IIEF-5) and Premature Ejaculation Diagnostic Tool (PEDT) questionnaires, respectively. Results identified 182 (60.7%) men had Met S. Prevalence of PE was significantly higher in the subjects with Met S than the controls (35.2% vs 7.6%, p?< 0.001). Patients with Met S and PE had significantly higher PEDT scores (15.4 vs 6.7), smaller waist circumference (108.3?cm vs 111.5?cm) and higher fasting blood sugar (187?mg% vs 161?mg%) than those with no PE (p?p?=?0.047 and <0.001, respectively) with PE in Met S. In conclusion, PE has a high prevalence in Met S. Patients with Met S should be questioned about PE. Both ED and systolic hypertension may be associated with PE. Prevention of Met S should be considered, and this may be of help to decrease the prevalence of PE.     

Prevalence,incidence and risk factors of testosterone deficiency in a population-based cohort of men: results from the study of health in Pomerania

Objective.?Low total testosterone levels (TT) have been associated with increased morbidity and mortality. However, the prevalence and incidence of testosterone deficiency (TD) in association with its risk has not been assessed systematically to date.

Methods.?Data from the prospective population-based Study of Health in Pomerania were used. From the 2117 men aged 20–79 years at baseline, 1490 men with complete TT data were analysed. Crude and age-specific prevalence and incidence rates of TD were estimated by TT levels below the age-specific 10th percentile. Analysis of covariance and Poisson regression models were used to assess the association of socio-demographic characteristics, health-related lifestyle, as well as somatometric, medical and laboratory measures with risk of incident TD.

Results.?TD baseline prevalence was 10.4% (N?=?155) and incidence 11.7 per 1000 person-years. TT levels showed a significant age-related decline with an unadjusted rate of 0.05 nmol/l per year. Obesity, metabolic syndrome, diabetes and dyslipidaemia were identified as risk factors of incident TD. Subpopulations of men without the revealed risk factors at both examinations maintained constant TT levels over time.

Conclusions.?Besides aging alone, lifestyle and different comorbidities were associated with TT level decline, suggesting that the age-related TT decline may be at least partly prevented through the management of potentially modifiable risk factors and health related behaviour.     

Pre-arrest drug use and associated risk factors among incarcerated offenders in China

ABSTRACT

Past research has consistently reported a higher rate of drug use before arrest among incarcerated inmates than that of the general population. However, there is a lack of either qualitative or quantitative research on this topic under the Chinese setting. Drawing upon survey data collected from 1,518 inmates in a Chinese province, this study attempts to fill in the research gap by assessing the connection between risk factors associated with pre-arrest use. Roughly a quarter of all inmates in the sample had the experience of drug use before arrest. Regression analysis suggested that impulsivity, volatile temper, and perceived prevalence of drug use in neighborhood were significantly related to drug use among inmates. Two control variables include offense type and stable job, were also found to be significant predictors of drug use. Implications for research and policy were highlighted in the end.     

Using repeated-prevalence data in multi-state modeling of renal replacement therapy

Multi-state models help predict future numbers of patients requiring specific treatments but these models require exhaustive incidence data. Deriving reliable predictions from repeated-prevalence data would be helpful. A new method to model the number of patients that switch between therapeutic modalities using repeated-prevalence data is presented and illustrated. The parameters and goodness of fit obtained with the new method and repeated-prevalence data were compared to those obtained with the classical method and incidence data. The multi-state model parameters’ confidence intervals obtained with annually collected repeated-prevalence data were wider than those obtained with incidence data and six out of nine pairs of confidence intervals did not overlap. However, most parameters were of the same order of magnitude and the predicted patient distributions among various renal replacement therapies were similar regardless of the type of data used. In the absence of incidence data, a multi-state model can still be successfully built with annually collected repeated-prevalence data to predict the numbers of patients requiring specific treatments. This modeling technique can be extended to other chronic diseases.