Autoregressive mixed effects models and an application to annual income of cancer survivors

Longitudinal observations of income are often strongly autocorrelated, even after adjusting for independent variables. We explore two common longitudinal models that allow for residual autocorrelation: 1. the autoregressive error model (a linear mixed effects model with an AR(1) covariance structure), and 2. the autoregressive response model (a linear mixed effects model that includes the first lag of the response variable as an independent variable). We explore the theoretical properties of these models and illustrate the behaviour of parameter estimates using a simulation study. Additionally, we apply the models to a data set containing repeated (annual) observations of income and sociodemographic variables on a sample of breast cancer survivors. Our preliminary results suggest that the autoregressive response model may severely overestimate the magnitude of the effect of cancer. Our findings will guide future, comprehensive study of the short- and long-term effects of a breast cancer diagnosis on a survivor’s annual net income

The Chemical Master Equation Approach to Nonequilibrium Steady-State of Open Biochemical Systems: Linear Single-Molecule Enzyme Kinetics and Nonlinear Biochemical Reaction Networks

We develop the stochastic, chemical master equation as a unifying approach to the dynamics of biochemical reaction systems in a mesoscopic volume under a living environment. A living environment provides a continuous chemical energy input that sustains the reaction system in a nonequilibrium steady state with concentration fluctuations. We discuss the linear, unimolecular single-molecule enzyme kinetics, phosphorylation-dephosphorylation cycle (PdPC) with bistability, and network exhibiting oscillations. Emphasis is paid to the comparison between the stochastic dynamics and the prediction based on the traditional approach based on the Law of Mass Action. We introduce the difference between nonlinear bistability and stochastic bistability, the latter has no deterministic counterpart. For systems with nonlinear bistability, there are three different time scales: (a) individual biochemical reactions, (b) nonlinear network dynamics approaching to attractors, and (c) cellular evolution. For mesoscopic systems with size of a living cell, dynamics in (a) and (c) are stochastic while that with (b) is dominantly deterministic. Both (b) and (c) are emergent properties of a dynamic biochemical network; We suggest that the (c) is most relevant to major cellular biochemical processes such as epi-genetic regulation, apoptosis, and cancer immunoediting. The cellular evolution proceeds with transitions among the attractors of (b) in a “punctuated equilibrium” manner

Cancer Patients’ Experiences with Telehealth before and during the COVID-19 Pandemic in British Columbia

Background: Patients have had their cancer care either postponed or changed to telehealth visits to reduce exposure to COVID-19. However, it is unclear how these changes may have affected their experiences. We aim to identify patient characteristics that affect telehealth experiences and evaluate their preferences for using telehealth in the future. Methods: Patients who completed the Outpatient Cancer Care (OCC) Patient Experience Survey were invited to participate. They comepleted the modified OCC Survey, which focused on telehealth during the pandemic. Linear and logistic regression analyses were used to identify patient characteristics that influenced telehealth experiences and preferences for future telehealth use. Results: Perceived ease of participation in telehealth is a significant predictor of the change in patients’ ratings of their telehealth experience. We found that cancer patients had lower preferences for using telehealth in the future if they were older, female, or non-white; resided in an urban area; had no previous telehealth experience; had lower education; and had poorer mental health. Conclusions: To optimize cancer care and improve equitable access to high-quality telehealth care during the pandemic and beyond, clinicians and policymakers will need to consider patients’ self-reported experiences and their personal characteristics.Applied Science, Faculty ofMedicine, Faculty ofNursing, School ofPopulation and Public Health (SPPH), School ofReviewedFacultyPostdoctoralOthe

Immunogenicity of a Two Dose Regimen of Moderna mRNA Beta/Omicron BA.1 Bivalent Variant Vaccine Boost in a Randomized Clinical Trial

We compared the serologic responses of one versus two doses of a variant vaccine (Moderna mRNA-1273 Beta/Omicron BA.1 bivalent vaccine) in adults. A two-dose boosting regimen with a variant vaccine did not increase the magnitude or the durability of the serological responses compared to a single variant vaccine boost

Immunogenicity of a Two Dose Regimen of Moderna mRNA Beta/Omicron BA.1 Bivalent Variant Vaccine Boost in a Randomized Clinical Trial.

We compared the serologic responses of one versus two doses of a variant vaccine (Moderna mRNA-1273 Beta/Omicron BA.1 bivalent vaccine) in adults. A two-dose boosting regimen with a variant vaccine did not increase the magnitude or the durability of the serological responses compared to a single variant vaccine boost