Using survival prediction techniques to learn consumer-specific reservation price distributions.

A consumer's "reservation price" (RP) is the highest price that s/he is willing to pay for one unit of a specified product or service. It is an essential concept in many applications, including personalized pricing, auction and negotiation. While consumers will not volunteer their RPs, we may be able to predict these values, based on each consumer's specific information, using a model learned from earlier consumer transactions. Here, we view each such (non)transaction as a censored observation, which motivates us to use techniques from survival analysis/prediction, to produce models that can generate a consumer-specific RP distribution, based on features of each new consumer. To validate this framework of RP, we run experiments on realistic data, with four survival prediction methods. These models performed very well (under three different criteria) on the task of estimating consumer-specific RP distributions, which shows that our RP framework can be effective.

The Pre-Registry Commercial Driver Medical Examination: Screening Sensitivity and Certification Lengths for Two Safety-Related Medical Conditions.

OBJECTIVE: Use independent diagnostic data to analyze the screening effectiveness of the pre-Registry commercial driver medical examination (CDME) for obstructive sleep apnea (OSA), and its sensitivity for hypertension; analyze certification lengths where relevant. METHODS: CDME screening results for 1668 drivers were compared to polysomnogram diagnostic test results, and CDME screening results were evaluated for 1155 drivers with at least one insurance claim with a hypertension diagnostic code. Any CDME documentation of the medical condition was considered as detection by screening. RESULTS: CDME sensitivity was 20.7% for moderate OSA (AHI ≥ 15). While sensitivity was 77.5% for hypertension, 93.3% of drivers with Stage 3 hypertension were certified, contrary to Federal Motor Carrier Safety Administration standards. CONCLUSIONS: The pre-Registry CDME was ineffective in screening commercial drivers for OSA. Screening was better for hypertension; incorrect certifications were given to many hypertensive drivers.

Employer-mandated obstructive sleep apnea treatment and healthcare cost savings among truckers.

OBJECTIVE: To evaluate the effect of an employer-mandated obstructive sleep apnea (OSA) diagnosis and treatment program on non-OSA-program trucker medical insurance claim costs. METHODS: Retrospective cohort analysis; cohorts constructed by matching (randomly, with replacement) Screen-positive Controls (drivers with insurance screened as likely to have OSA, but not yet diagnosed) with Diagnosed drivers (n = 1,516; cases = 1,224, OSA Negatives = 292), on two factors affecting exposure to medical claims: experience level at hire and weeks of job tenure at the Diagnosed driver's polysomnogram (PSG) date (the "matching date"). All cases received auto-adjusting positive airway pressure (APAP) treatment and were grouped by objective treatment adherence data: any "Positive Adherence" (n = 932) versus "No Adherence" (n = 292). Bootstrap resampling produced a difference-in-differences estimate of aggregate non-OSA-program medical insurance claim cost savings for 100 Diagnosed drivers as compared to 100 Screen-positive Controls before and after the PSG/matching date, over an 18-month period. A two-part multivariate statistical model was used to set exposures and demographics/anthropometrics equal across sub-groups, and to generate a difference-in-differences comparison across periods that identified the effect of OSA treatment on per-member per-month (PMPM) costs of an individual driver, separately from cost differences associated with adherence choice. RESULTS: Eighteen-month non-OSA-program medical claim costs savings from diagnosing (and treating as required) 100 Screen-positive Controls: $153,042 (95% CI: -$5,352, $330,525). Model-estimated effect of treatment on those adhering to APAP: -$441 PMPM (95% CI: -$861, -$21). CONCLUSIONS: Results suggest a carrier-based mandatory OSA program generates substantial savings in non-OSA-program medical insurance claim costs.

Longitudinal Analysis of CAD/CAM Restoration Incorporation Rates into Navy Dentistry.

INTRODUCTION: Computer-aided design/computer-aided manufacturing (CAD/CAM) has gained increasing popularity since the first commercially viable dental system was introduced in the mid-1980s. Digitally milled dental restorations can be fabricated chairside in the course of one dental appointment, reducing time, cost, and manpower when compared with traditional laboratory-fabricated analog restorations. Clinical performance, physical properties, and esthetics of digital restorations have been shown to be comparable to traditional analog restorations. The Navy has incorporated CAD/CAM systems into dental clinics on multiple platforms to include ships. The efficiency of this technology has the potential to positively impact dental health and mission readiness. The objective of the present study was to evaluate placement rates of CAD/CAM restorations by Navy dental providers. MATERIALS AND METHODS: Placement rates of CAD/CAM restorations from October 2011 to June 2017 (Department of Defense created codes specific to CAD/CAM restorations in 2011) and of laboratory-fabricated analog restorations from January 2008 to June 2017 were queried from the Dental Common Access System (DENCAS) and Corporate Dental Access system (CDA) and evaluated. Scatterplots for each dental restoration category were generated using monthly production data and overlaid with simple linear regression lines and 95% confidence intervals. Regression analysis was performed to determine whether changes in the monthly percentages of placements before and after CAD/CAM were increasing or decreasing and to determine whether the monthly percent change from before CAD/CAM implementation and after CAD/CAM implementation was significantly different from one another. RESULTS: A total of 20,512 CAD/CAM restorations were placed by Navy providers over the 68-month period. A year-over-year increase in digitally fabricated restorations was observed. As a percentage of total indirect restorations, CAD/CAM units surged from 13.8% in 2012 to 38.1% in 2017. All ceramic restorations fabricated by the classical analog method also increased significantly through the period. Traditional analog porcelain fused to metal (PFM) restorations and large amalgam restorations, which frequently serve a similar clinical purpose as indirect or direct full or partial tooth coverage restorations, both decreased significantly after CAD/CAM productivity tracking was initiated. CONCLUSIONS: Implementation of CAD/CAM digital restorations has led to a significant decline in specific traditional analog procedures since productivity tracking of CAD/CAM was initiated in 2011. Navy dentistry has embraced CAD/CAM as an efficient means to prepare sailors and marines for deployments, improve operational dental readiness, and potentially decrease dental emergencies by reducing the need for provisional restorations. The trend toward increased utilization of digital dentistry is expected to continue for the following reasons: (1) incorporation of CAD/CAM technology into dental school curricula, (2) advancement of CAD/CAM systems equipped with fast-evolving user interfaces, (3) increased accessibility to CAD/CAM technology in Navy clinics, and (4) training of a greater proportion of dentists in digital CAD/CAM technology. Future studies should investigate the survival rate of CAD/CAM restorations placed within military settings, cost, and manpower of maintaining CAD/CAM units, and impact on military dental laboratories associated with increased CAD/CAM usage.