Adverse selection and health insurance decisions of young migrant workers: An empirical study in China.

Using data from the China Migrants Dynamic Survey (CMDS) in 2017, this study assessed adverse selection and the impact of mobility factors on adverse selection by analyzing two samples of young migrant workers. The results of the sample analysis showed that young migrant workers with higher health risks were more inclined to enroll in health insurance, indicating the presence of adverse selection. Mobility distance and settle intention have a heterogeneous effect on adverse selection, with young workers who migrate inter-provincially and intend to settle down being more susceptible. The analysis of the insured samples showed that the phenomenon of adverse selection was also evident in the choice of health insurance, with individuals with higher risks preferring Urban Employee Basic Medical Insurance (UEBMI), which has better financial coverage and benefits compared to Rural Residents' Basic Medical Insurance (URRBMI). The heterogeneity test confirmed that mobility distance plays a role in determining the likelihood of adverse selection, with inter-city and inter-province young migrant workers being more likely to show adverse selection.

Understanding Public Perspectives on Fracking in the United States using Social Media Big Data.

People's attitudes toward hydraulic fracturing (i.e., "fracking") to extract fossil fuels can be shaped by factors associated with socio-demographics, economic development, social equity and politics, environmental impacts, and fracking-related information obtainment. Existing research typically conducts surveys and interviews to study public attitudes toward fracking among a small group of individuals in a specific geographic area, where limited samples may introduce bias. Here, we compiled geo-referenced social media big data from Twitter during 2018-2019 for the entire United States to present a more holistic picture of people's attitudes toward fracking. We used a multiscale geographically weighted regression (MGWR) to investigate county-level relationships between the aforementioned factors and percentages of negative tweets concerning fracking. Results clearly depict spatial heterogeneity and varying scales of those associations. Counties with higher median household income, larger African American populations, and/or lower educational level are less likely to oppose fracking, and these associations show global stationarity in all contiguous U.S. counties. Eastern and Central U.S. counties with higher unemployment rate, counties east of the Great Plains with less fracking sites nearby, and Western and Gulf Coast region counties with higher health insurance enrollments are more likely to oppose fracking activities. These three variables show clear East-West geographical divides in influencing public perspective on fracking. In counties across the southern Great Plains, negative attitudes toward fracking are less often vocalized on Twitter as the share of Republican voters increases. These findings have implications for both predicting public perspectives and needed policy adjustments. The methodology can also be conveniently applied to investigate public perspectives on other controversial topics.

A multi-modal relative spatial access assessment approach to measure spatial accessibility to primary care providers.

Two-step floating catchment area (2SFCA) methods that account for multiple transportation modes provide more realistic accessibility representation than single-mode methods. However, the use of the impedance coefficient in an impedance function (e.g., Gaussian function) introduces uncertainty to 2SFCA results. This paper proposes an enhancement to the multi-modal 2SFCA methods through incorporating the concept of a spatial access ratio (SPAR) for spatial access measurement. SPAR is the ratio of a given place's access score to the mean of all access scores in the study area. An empirical study on spatial access to primary care physicians (PCPs) in the city of Albuquerque, NM, USA was conducted to evaluate the effectiveness of SPAR in addressing uncertainty introduced by the choice of the impedance coefficient in the classic Gaussian impedance function. We used ESRI StreetMap Premium and General Transit Specification Feed (GTFS) data to calculate the travel time to PCPs by car and bus. We first generated two spatial access scores-using different catchment sizes for car and bus, respectively-for each demanding population location: an accessibility score for car drivers and an accessibility score for bus riders. We then computed three corresponding spatial access ratios of the above scores for each population location. Sensitivity analysis results suggest that the spatial access scores vary significantly when using different impedance coefficients (p < 0.05); while SPAR remains stable (p = 1). Results from this paper suggest that a spatial access ratio can significantly reduce impedance coefficient-related uncertainties in multi-modal 2SFCA methods.

Macular integrity assessment to determine the association between macular microstructure and functional parameters in diabetic macular edema.

AIM: To respectively evaluate macular morphological features and functional parameters by using spectral-domain optical coherence tomography (SD-OCT) and macular integrity assessment (MAIA) in patients with diabetic macular edema (DME). METHODS: This prospective, non-controlled, open study included 61 eyes of 38 consecutive patients with DME. All patients underwent best-corrected visual acuity (BCVA) measurement, MAIA microperimetry, and SD-OCT. DME morphology, including central retinal thickness (CRT) and central retinal volume (CRV); integrity of the external limiting membrane (ELM) and photoreceptor inner segment/outer segment (IS/OS) junction; and the deposition of hard macular exudates were assessed within a 1000-µm central subfield area. MAIA microperimetry parameters evaluated were average threshold (AT)-retinal sensitivity, macular integrity index (MI), fixation points within a circle of radius 1° (P1) and 2° (P2), and bivariate contour ellipse area considering 63% and 95% of the fixation points (A63 and A95, respectively). RESULTS: MI was significantly higher in eyes with disrupted ELM or IS/OS, compared with eyes with intact ELM and IS/OS. Values of BCVA (logMAR), total AT, AT within 1000-µm diameter, P2, A63, A95, and CRT were significantly worse in eyes with disrupted IS/OS, compared with eyes with intact IS/OS. The values of BCVA (logMAR), AT within 1000-µm diameter, and CRT were significantly worse in eyes with disrupted ELM, compared with eyes with intact ELM. These parameters were not significantly different between eyes with or without hard macular exudate deposition. CRV was not significantly different in the presence or absence of the integrity of ELM, IS/OS, or deposition of hard macular exudates. At the center, nasal and temporal sectors of the fovea, significant negative correlations were observed between retinal thickness and AT of the corresponding area. At the inferior and superior sectors of the fovea, no correlations were observed between retinal thickness and AT of the corresponding area. In the intact IS/OS group, significant negative correlations were observed between CRT and central AT. There was no correlation between retinal sensitivity and thickness when the IS/OS layer was disrupted. Multiple linear regression analyses revealed that IS/OS integrity was an independent factor affecting MI. CONCLUSION: Functional (BCVA and visual field) and morphological parameters (retinal thickness) were significantly associated with an intact IS/OS. Local photoreceptor integrity was a strong predictor of local visual function throughout the retina. MI revealed the functional status in DME, reflecting the IS/OS juction status in the macula.

Diagnostic values of 3 methods for evaluating meniscal healing status after meniscal repair: comparison among second-look arthroscopy, clinical assessment, and magnetic resonance imaging.

BACKGROUND: The main diagnostic methods for evaluating repaired menisci include second-look arthroscopy, clinical assessment, and magnetic resonance imaging (MRI). None of the previous studies applied all 3 methods for each consecutive case nor made any systematic comparison among them. PURPOSE: This study was undertaken to compare the diagnostic values of the 3 different methods in an attempt to propose suggestions for evaluating meniscal healing results. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: Eighty-one patients (89 menisci), with a mean age of 25.4 years (standard deviation [SD], 7.7; range, 15-50 years), underwent arthroscopic meniscal repair, including 65 medial menisci and 24 lateral menisci. Follow-up evaluation for each meniscus included clinical assessment, second-look arthroscopy, and postoperative MRI, with a mean follow-up time of 25.4 months (SD, 6.0; range, 17.4-48.3 months). Defined criteria for unhealed meniscus were any symptoms such as joint-line tenderness, swelling, locking, or positive McMurray test for clinical assessment; cleft or instability on second-look arthroscopy; and grade 3 signal intensity shown at the repaired site on postoperative MRI. RESULTS: Seventy-seven menisci were confirmed completely healed by second-look arthroscopy, with a total healing rate of 86.5%. Clinical assessment found 63 menisci healed, with a clinical healing rate of 70.8% (sensitivity, 58.3%; specificity, 75.3%; accuracy, 73.0%). By using the second-look arthroscopy as the standard, the sensitivity, specificity, and accuracy, respectively, were calculated for MRI in 5 sequences: sagittal T1: 91.7%, 58.4%, 62.9%; sagittal proton density (PD): 83.3%, 40.3%, 46.1%; sagittal T2: 58.3%, 89.6%, 85.4%; coronal PD: 75.0%, 74.0%, 74.2%; and coronal T2: 41.7%, 98.7%, 91.0%. CONCLUSION: Second-look arthroscopy was the most dependable way to determine meniscal healing. Clinical assessment had obvious limitations in diagnosing healed menisci. On MRI examination, T2-weighted sequences had obviously higher specificity and accuracy, while PD and T1 had higher sensitivity. The diagnostic value could be improved by a combined application of different sequences.