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Much of classical optimal design theory relies on specifying a model with only a small number of parameters. In many applications, such models will give reasonable approximations. However, they will often be found not to be entirely correct when enough data are at hand. A property of classical optimal design methodology is that the amount of data does not influence the design when a fixed model is used. However, it is reasonable that a low dimensional model is satisfactory only if limited data is available. With more data available, more aspects of the underlying relationship can be assessed. We consider a simple model that is not thought to be fully correct. The model misspecification, that is, the difference between the true mean and the simple model, is explicitly modeled with a stochastic process. This gives a unified approach to handle situations with both limited and rich data. Our objective is to estimate the combined model, which is the sum of the simple model and the assumed misspecification process. In our situation, the low-dimensional model can be viewed as a fixed effect and the misspecification term as a random effect in a mixed-effects model. Our aim is to predict within this model. We describe how we minimize the prediction error using an optimal design. We compute optimal designs for the full model in different cases. The results confirm that the optimal design depends strongly on the sample size. In low-information situations, traditional optimal designs for models with a small number of parameters are sufficient, while the inclusion of the misspecification term lead to very different designs in data-rich cases.

Financial counseling has been found to be effective in improving consumers' credit outcomes and could be expanded through the workplace to reach lower-income workers who struggle with various financial challenges. We examine engagement and credit outcomes associated with a workplace financial counseling program offered to 2,849 frontline workers in New York City. Age and credit scores helped explain variation in types of engagement in services. Credit outcomes were modest on average, but greater among workers who received three or more counseling sessions, had low and no baseline credit scores, and reduced the number of delinquent and collections accounts on their credit reports. Workplace financial counseling is a promising strategy to proactively promote credit outcomes among frontline workers, though counselors should be flexible in offering services and help workers access affordable credit products available to those with subprime credit scores and increase financial slack to lessen dependence on credit.

Whether to repair nonsevere tricuspid regurgitation (TR) during surgery for ischemic mitral valve regurgitation (IMR) remains uncertain.The goal of this study was to investigate the incidence, predictors, and clinical significance of TR progression and presence of ≥moderate TR after IMR surgery.Patients (n = 492) with untreated nonsevere TR within 2 prospectively randomized IMR trials were included. Key outcomes were TR progression (either progression by ≥2 grades, surgery for TR, or severe TR at 2 years) and presence of ≥moderate TR at 2 years.Patients' mean age was 66 ± 10 years (67% male), and TR distribution was 60% ≤trace, 31% mild, and 9% moderate. Among 2-year survivors, TR progression occurred in 20 (6%) of 325 patients. Baseline tricuspid annular diameter (TAD) was not predictive of TR progression. At 2 years, 37 (11%) of 323 patients had ≥moderate TR. Baseline TR grade, indexed TAD, and surgical ablation for atrial fibrillation were independent predictors of ≥moderate TR. However, TAD alone had poor discrimination (area under the curve, ≤0.65). Presence of ≥moderate TR at 2 years was higher in patients with MR recurrence (20% vs. 9%; p = 0.02) and a permanent pacemaker/defibrillator (19% vs. 9%; p = 0.01). Clinical event rates (composite of ≥1 New York Heart Association functional class increase, heart failure hospitalization, mitral valve surgery, and stroke) were higher in patients with TR progression (55% vs. 23%; p = 0.003) and ≥moderate TR at 2 years (38% vs. 22%; p = 0.04).After IMR surgery, progression of unrepaired nonsevere TR is uncommon. Baseline TAD is not predictive of TR progression and is poorly discriminative of ≥moderate TR at 2 years. TR progression and presence of ≥moderate TR are associated with clinical events. (Comparing the Effectiveness of a Mitral Valve Repair Procedure in Combination With Coronary Artery Bypass Grafting [CABG] Versus CABG Alone in People With Moderate Ischemic Mitral Regurgitation, NCT00806988; Comparing the Effectiveness of Repairing Versus Replacing the Heart's Mitral Valve in People With Severe Chronic Ischemic Mitral Regurgitation, NCT00807040).

Interest among employers is growing in employee financial wellness programs (EFWPs), a new type of benefit to address financial stress among employees. EFWP benefits include financial counseling, small-dollar loans, and savings programs that address employees’ nonretirement financial needs. Little evidence exists concerning the availability and use of and outcomes associated with EFWPs, especially among low- and moderate-income (LMI) workers who may be in the greatest need of these benefits. We present findings concerning awareness and use of EFWPs from a national survey of LMI workers ( N = 16,650). Availability of different EFWP benefits ranged from 11 to 15% and over a third of workers were unaware of whether their employer offered an EFWP. Experiencing financial difficulties predicted both EFWP awareness and use suggesting that employers should take time to assess employees’ specific financial challenges to select benefits. Yet, use of EFWPs by LMI workers may suggest the need for better compensation and work conditions.

Employee financial wellness programs (EFWPs) are a new practice that may promote financial inclusion by making it easier for workers with low- and moderate-incomes (LMI) to access financial service...

Relative to non-Indigenous youth, Indigenous youth have been under-represented when studying pathways to mental wellness. Yet, a broad range of adversity is acknowledged, from intergenerational and ongoing trauma arising from colonial policies. This scoping review explores resilience definitions, measures, key stressors, and what Indigenous youth identify as pathways to their wellness, based on quantitative and qualitative peer-reviewed literature in Canada and the Continental United States. Eight databases (

Employee financial wellness programs (EFWPs) are a benefit innovation that promise to address the financial challenges of employees while also benefiting employers. Results from a mixed-methods stu...

Dose-finding is an important part of the clinical development of a new drug. The purpose of dose-finding studies is to determine a suitable dose for future development based on both efficacy and safety. Optimal experimental designs have already been used to determine the design of this kind of studies, however, often that design is focused on efficacy only. We consider an efficacy-safety model, which is a simplified version of the bivariate Emax model. We use here the clinical utility index concept, which provides the desirable balance between efficacy and safety. By maximizing the utility of the patients, we get the estimated dose. This desire leads us to locally c -optimal designs. An algebraic solution for c -optimal designs is determined for arbitrary c vectors using a multivariate version of Elfving's method. The solution shows that the expected therapeutic index of the drug is a key quantity determining both the number of doses, the doses itself, and their weights in the optimal design. A sequential design is proposed to solve the complication of parameter dependency, and it is illustrated in a simulation study.

The availability of consumer remotely piloted aircraft systems (RPAS) has enabled rapidly deployable airborne surveys for civilian applications. Combined with photogrammetric reconstruction techniques, such as Structure-from-Motion (SfM), it has become increasingly feasible to survey large areas with very high resolution, especially when compared with other airborne or spaceborne surveying techniques. A pair of case studies, using an RPAS-based field surveying technique for establishing baseline surface models in steep terrain, are presented for two different natural hazard applications.The first case study involved a survey over the entire 1000-m length of a snow-free avalanche path on Sætreskarsfjellet in Stryn municipality in Norway. A terrain-aware, multi-battery flight plan was designed to ensure good photographic coverage over the entire avalanche path and 21 ground control points (GCP) were distributed evenly across the path and subsequently surveyed. More than 400 images were collected over a 0.5 km2 area, which were processed using a commercial SfM software package. Two digital surface models were reconstructed, each utilizing a different ground control scenario: the first one with the full count of GCP, while the second used only a limited count of GCP, which is more feasible for a repeat survey when avalanche hazard is high. Comparison with data from a pre-existing, airborne LiDAR survey over the avalanche path revealed that the SfM-derived model that utilized only a limited number of GCP diverged significantly from the model that utilized all available GCP. Further differences between the SfM- and LiDAR-derived surface models were observed in areas with very steep slopes and vegetative cover. The same methodology can subsequently be applied during the winter season, after extensive snowfall and/or avalanche events, to deduce relevant avalanche parameters such as snow height, snow distribution and drift, opening of cracks in the snow surface (e.g. for glide avalanches), and avalanche outlines.The second case study involved a survey over the entire 1000-m length of a debris flow path at Årnes in Jølster, Norway. The Årnes flow, which caused one fatality, was one of the largest of several tens of debris flows that occurred on July 30, 2019. The flows were triggered by an extreme precipitation event around the Jølstravatnet area. Like with the Sætreskarsfjellet avalanche path case study, a terrain-aware flight plan was established and 24 GCP were distributed and surveyed along the debris flow path. Over 400 images were collected over a 0.3 km2 area, which were used to reconstruct a high-resolution surface model. Like with the avalanche case study, the SfM-derived model was compared with a pre-existing LiDAR survey-derived digital terrain model. Altitude and volume changes, due to the debris flow event, were calculated using GIS analysis tools.The utility of the RPAS survey technique was demonstrated in both case studies, despite difficult accessibility for ground control. It is suggested that a real-time-kinematic (RTK)-enabled workflow may significantly reduce survey time and increase personnel safety by minimizing the number of required GCP.Keywords: Structure-from-Motion, photogrammetry, digital surface model, natural hazards, ground control.

To determine the frequency and risk factors for non-home discharge (NHD) and its association with clinical outcomes and quality of life (QOL) at 1 year following cardiac surgery in patients with ischemic mitral regurgitation (IMR).Discharge disposition was evaluated in 552 patients enrolled in trials of severe or moderate IMR. Patient and in-hospital factors associated with NHD were identified using logistic regression. Subsequently, association of NHD with 1-year mortality, serious adverse events (SAEs), and QOL was assessed.NHD was observed in 30% (154/522) with 25% (n = 71/289) in moderate and 36% (n = 83/233) in patients with severe IMR (unadjusted P = .006), a difference not significant after including age (5-year change: adjusted odds ratio [adjOR], 1.52; 95% confidence interval [CI], 1.35-1.72; P .001), diabetes (adjOR, 1.94; 95% CI, 1.27-2.94; P = .002), and previous heart failure (adjOR, 1.64; 95% CI, 1.06-2.52; P = .03). Odds of NHD were increased for patients with postoperative SAEs (adjOR, 1.85; 95% CI, 1.19-2.86; P = .01) but not based on type of cardiac surgery. Greater rates of death and SAEs were observed in NHD patients at 1 year: adjusted hazard ratio, 4.29 (95% CI, 2.14-8.59; P .001) and adjusted rate ratio, 1.45 (95% CI, 1.03-2.02; P = .03), respectively. QOL did not differ significantly between groups.NHD is common following surgery for IMR, influenced by older age, diabetes, previous heart failure, and postoperative SAEs. These patients may be at greater risk of death and subsequent SAEs after discharge. Discussion of NHD with patients may have important implications for decision-making and guiding expectations following cardiac surgery.