Uniformity test based on the empirical Bernstein distribution

In this paper, we firstly review the origin of Bernstein polynomial and the various application of it. Then we review the importance of goodness-of-fit test, especially the uniformity test, and we examine lots of different test statistics proposed by far. After that we suggest two new statistics for testing the uniformity. These two statistics are based on Komogorov-Smirnov test type and Cramér-Von Mises test type, respectively. Also we embed Bernstein polynomial into those test type and take advantage of great approximation performance of this polynomial. Finally, we run a Monte-Carlo simulation to compare the performance of our statistics to those without embedding the Bernstein polynomials. We compare their performance in term of powers and inefficiencies. We found that by choosing suitable value for parameter, our statistics can perform better than the original form in most of the cases. The suggestion of choosing optimal value will be given

PATIENT PORTAL USE AND ITS ASSOCIATION WITH CLINICAL OUTCOMES IN PATIENTS WITH TYPE 2 DIABETES

Background: The rapid growth of type 2 diabetes mellitus (T2DM) in the United States presents significant challenges. Patient portals are promising tools that address the increasing number of individuals with T2DM and engage these people in the process of managing their chronic condition. Objectives: The purposes of this study were: 1) to describe the portal usage pattern by individuals with T2DM over the two-year study period; 2) to identify whether sociodemographic, socioeconomic, and clinical characteristics differ between portal users and non-users; and 3) to longitudinally examine the effect of portal use on glycemic control in patients with T2DM. Methods: This two-year retrospective, observational cohort study utilized data from the ambulatory electronic health records (EHR) of the University of Pittsburgh Medical Center (UPMC) Physician Services and its ancillary patient portal. The study included adults seen in an outpatient setting of UPMC between January 2015 and December 2016. We applied descriptive statistics to describe sample characteristics and portal usage patterns. Logistic regression was used to examine factors associated with portal use. A propensity score matching (PSM) technique was conducted to equate the portal user and non-user groups, and mixed modeling was performed to examine the effect of portal use on hemoglobin A1c (HbA1c) over time. Results: Nearly one-third of the individuals (n=12,615, 32.9%, 95% CI: [32.3%,33.3%]) with T2DM used the portals. An increased portal usage was observed before and after a physician visit, and on weekdays compared to weekends (p<0.001). In general, we found associations of age, race, income, and the number of chronic conditions with portal usage, and several other predictors modified these effects (ps<0.05). After PSM, both groups showed a non-linear decline of HbA1c over time (p<.001), and the portal users (n=4,924) demonstrated a greater decrease and better maintenance than the non-users (n=4,924, p<.001). Conclusions: Our findings highlight the promising effect of a patient portal on clinical glycemic control in persons with T2DM. Disparities in patient portals need to be addressed to bridge the existing gaps in diabetes outcomes. Future study should explore mechanisms through which the portal contributes to better clinical outcomes to guide evidence-based portal design and implementation