Multi-sample standardization and decomposition analysis: an application to comparisons of methamphetamine use among rural drug users in three American states

Partitioning of time trends in prevalence and mortality of lung cancer

BACKGROUND

Time trends of lung cancer prevalence and mortality are the result of three competing processes: changes in the incidence rate, stage-specific survival, and ascertainment at early stages. Improvements in these measures act concordantly to improve disease-related mortality, but push the prevalence rate in opposite directions making a qualitative interpretation difficult. The goal of this paper is to evaluate the relative contributions of these components to changes in lung cancer prevalence and mortality.

METHODS

Partitioning of prevalence and mortality trends into their components using SEER data for 1973-2013.

RESULTS

The prevalence of lung cancer increases for females and decreases for males. In 1998, the former was due to increased incidence (45%-50% of total trend), improved survival (40%-45%), and increased ascertainment at early stages (10%-15%). In males, a rapidly declining incidence rate overpowered the effects of survival and ascertainment resulting in an overall decrease in prevalence over time. Trends in lung cancer mortality are determined by incidence during 1993-2002 with noticeable contribution of survival after 2002.

CONCLUSION

Lung cancer incidence was the main driving force behind trends in prevalence and mortality. Improved survival played essential role from 2000 onwards. Trends in stage ascertainment played a small but adverse role. Our results suggest that further improvement in lung cancer mortality can be achieved through advances in early stage ascertainment, especially for males, and that in spite of success in treatment, adenocarcinoma continues to exhibit adverse trends (especially in female incidence) and its role among other histology-specific lung cancers will increase in the near future.

Standardization of medical service indicators: A useful technique for hospital administration

Background

Many comparability problems appear in the process of the performance assessment of medical service. When comparing medical evaluation indicators across hospitals, or even within the same hospital, over time, the differences in the population composition such as types of diseases, comorbidities, demographic characteristics should be taken into account. This study aims to introduce a standardization technique for medical service indicators and provide a new insight on the comparability of medical data.

Methods

The medical records of 142592 inpatient from three hospitals in 2017 were included in this study. Chi-square and Kruskal-Wallis tests were used to explore the compositions of confounding factors among populations. The procedure of stratified standardization technique was applied to compare the differences of the average length of stay and the average hospitalization expense among three hospitals.

Results

Age, gender, comorbidity, and principal diagnoses category were considered as confounding factors. After correcting all factors, the average length of stay of hospital A and C were increased by 0.21 and 1.20 days, respectively, while that of hospital B was reduced by 1.54 days. The average hospitalization expenses of hospital A and C were increased by 1494 and 660 Yuan, whilst that of hospital B was decreased by 810 Yuan.

Conclusions

Standardization method will be helpful to improve the comparability of medical service indicators in hospital administration. It could be a practical technique and worthy of promotion.

Self-efficacy difference among patients with cancer with different socioeconomic status: application of latent class analysis and standardization and decomposition analysis

INTRODUCTION

Although the relationship between partial socioeconomic status (SES) and self-efficacy has been studied in previous studies, few research have examined self-efficacy difference among patients with cancer with different SES.

METHODS

A cross-sectional survey involving 764 patients with cancer was completed. Latent class analysis (LCA) was applied to identify distinct groups of patients with cancer using four SES indicators (education, income, employment status and health insurance status). Standardization and decomposition analysis (SDA) was then used to examine differences in patients' self-efficacy among SES groups and the components of the differences attributed to confounding factors, such as gender, age, anxiety, depression and social support.

RESULTS

Participants were classified into four distinctive SES groups via using LCA method, and the observed self-efficacy level significantly varied by SES groups; as theorized, higher self-efficacy was associated with higher SES. The self-efficacy differences by SES groups were decomposed into "real" group differences and factor component effects that are attributed to group differences in confounding factor compositions.

CONCLUSION

Self-efficacy significantly varies by SES. Social support significantly confounded the observed differences in self-efficacy between different SES groups among Chinese patients with cancer.

Days with pain and substance use disorders: is there an association?

OBJECTIVES

We investigated possible associations between pain frequency and the 5 most common substance use disorders: alcohol abuse/dependence, cocaine abuse/dependence, methamphetamine abuse/dependence, opioid abuse/dependence, and marijuana abuse/dependence.

METHODS

We used data from the Rural Stimulant Study, a longitudinal (7 waves), observational study of at-risk stimulant users (cocaine and methamphetamine) in Arkansas and Kentucky (n=462). In fixed-effects logistic regression models, we regressed our measures of substance use disorders on the number of days with pain in the past 30 days and depression severity.

RESULTS

Time periods when individuals had 1 to 15 days [odds ratio (OR)=1.85, P<0.001] or 16+ days (OR=2.18, P<0.001) with pain in the past 30 days were more likely to have a diagnosis of alcohol abuse/dependence, compared with time periods when individuals had no days with pain. Compared with time periods when individuals had no pain days in the past 30 days, time periods when individuals had 16+ pain days were more likely to have a diagnosis of opioid abuse/dependence (OR=3.32, P=0.02). Number of days with pain was not significantly associated with other substance use disorders.

DISCUSSION

Pain frequency seems to be associated with an increased risk for alcohol abuse/dependence and opioid abuse/dependence in this population, and the magnitude of the association is medium to large. Further research is needed to investigate this in more representative populations and to determine causal relationships.

Regional differences in HIV prevalence and individual attitudes among service providers in China

We examined the relationships between a region's HIV prevalence and HIV-related knowledge, perceived risk of HIV infection, perceived institutional support for HIV care, and avoidance attitude toward persons living with HIV (PLH) among service providers in China. Data were collected from 40 county-level hospitals in two provinces, including 1760 service providers. Multi-sample standardization and decomposition analysis was performed for HIV knowledge, perceived risk, institutional support, and avoidance attitude toward PLH. After adjusting for potential confounders, service providers from the province with higher HIV prevalence perceived a higher risk of contracting HIV at work, recognized more institutional support for HIV care, and reported a lower level of avoidance attitude toward PLH compared to those from the province with lower HIV prevalence. After confounding factors were standardized across provinces, occupational exposure experience was determined to be the strongest influence on the discrepancy of avoidance attitudes in the two provinces. Regional contextual factors could shape individual providers' attitudes and beliefs and impact the quality of care. Stigma reduction interventions need to be culturally tailored and region-specific.

Methamphetamine use, dependence and treatment access in rural and regional North Coast of New South Wales, Australia

INTRODUCTION AND AIMS

To identify the sociodemographic, health, drug use patterns, treatment coverage and barriers to treatment among regular methamphetamine users in rural and regional North Coast of New South Wales.

DESIGN AND METHODS

A structured questionnaire was used to measure sociodemographic factors, health and well-being, drug use patterns, methamphetamine dependence, engagement in methamphetamine treatment and barriers to treatment. Participants were 140 regular methamphetamine users. Dependent and non-dependent participants were compared to identify factors associated with dependence.

RESULTS

Participants were predominantly in their thirties, male and had low levels of education, high levels of unemployment and polydrug use. Participants who were dependent on methamphetamine (59%) were more likely to report impaired mental health and to have been diagnosed with depression, anxiety and drug-induced psychosis. One quarter of dependent methamphetamine users had received treatment in the last year and half had ever received treatment. The main barriers to receiving treatment were a lack of perceived need or motivation to seek treatment and concerns about confidentiality.

DISCUSSION AND CONCLUSIONS

Methamphetamine users living on the North Coast of New South Wales require treatment options tailored to address a complex array of physical and psychological problems. The findings highlight the need for psychiatric support and improved coordination between mental health and drug and alcohol services in rural and regional areas.