Fredrik Ødegaard

US-guided therapy of calcific tendinopathy: clinical and radiological outcome assessment in shoulder and non-shoulder tendons.

PURPOSE To analyze the effectiveness and complication rate of ultrasound (US)-guided perforation and lavage using a two-needle technique with 16 - 18 G needles in the treatment of patients with calcific tendinopathy in the shoulder, elbow, hip, and knee by radiological and clinical follow-up. MATERIALS AND METHODS A retrospective chart review was performed and 40 patients (13 male, 27 female; mean age, 53.5 years; range 24 -74 years) were identified as having received US-guided perforation and lavage due to symptomatic calcific tendinopathy of the rotator cuff tendons, triceps, extensor and flexor tendons at the elbow, rectus femoris tendon and patellar tendons. The radiographic outcome was assessed by comparison of the size and quality of the calcification before and 6 weeks after the procedure. On US images, the quality of the acoustic shadow was assessed, together with other alterations of the tendon and surrounding tissue. Patients were interviewed by telephone to assess the clinical outcome regarding pre-treatment and post-treatment pain and tendon function. RESULTS 34 shoulder tendons and 6 non-shoulder tendons were identified. The mean calcium reduction was 39.9 mm(2) (range, 0 - 215; p < 0.001), while 80 % of patient showed a resolution of more than 60 % resulting in good clinical improvement. A very low complication rate was found (1 partial tear). CONCLUSION The US-guided perforation and lavage technique is an effective and safe treatment for rotator cuff calcifications as well as for other body tendons. Although the two-needle technique and large needles were used in this study, a very low complication rate was detected.

Improving the Efficiency of Hospital Porter Services, Part 1: Study Objectives and Results

&NA; This article is the first of a 2‐part series reporting the results of a 7‐month study of porter operations at Vancouver General Hospital, Vancouver, British Columbia, Canada. Part 1 describes the importance of efficient porter services, the systems operation at the time of the study, the challenges faced in carrying out the study, the performance measures developed, the recommendations, and the outcomes. Part 2 describes the simulation model that measured the impact of system changes and the linear programming model developed to improve porter schedules.

Dynamic pricing of primary products and ancillary services

Motivated by the growing prevalence for airlines to charge for checked baggage, this paper studies pricing of primary products and ancillary services. We consider a single seller with a fixed capacity or inventory of primary products that simultaneously makes an ancillary service available, e.g. a single-leg flight and checked baggage service. The seller seeks to maximize total expected revenue by dynamically setting prices on both the primary product and the ancillary service. In each period, a random number of customers arrive each of whom may belong to one of three groups: those that only want the primary products, those that would buy the ancillary service if the price is right, and those that only purchase a primary product together with the ancillary service. A multi-period dynamic pricing model is presented with computational complexity only of order equal to the number of periods. For certain distributions, close to analytical results can be obtained from which structural insights may be gleaned.

Improving the Efficiency of Hospital Porter Services, Part 2: Schedule Optimization and Simulation Model

&NA; This article is the second of a 2‐part series on a study of porter operations at Vancouver General Hospital, Vancouver, British Columbia, Canada. Part 1 describes the importance of efficient porter services, the systems operation at the time of the study, the challenges faced in carrying out the study, the performance measures developed, the recommendations, and the outcomes. Part 2 describes the simulation model that measured the impact of system changes and the linear programming model developed to improve porter schedules.

Optimal product bundling with dependent valuations: The price of independence

In this paper we investigate the tactical problem of pricing a bundle of products when the underlying valuations of the bundle components are dependent. We use copula theory to model the joint density of reservation prices and provide analytical derivations for the prices under different bundling strategies and sharp bounds for the profit function. We discover that when only the bundle is offered and the marginal costs are relatively small, the seller is better off by bundling products that have a negative association between their valuations, while the converse is true when the marginal costs are relatively high. We also show that the net benefit of offering a full product line containing both the bundle and the components decreases for mild to strong associations between the component valuations, compared to offering just the bundle. Finally, we analyze how the typical literature assumption of independence of reservation prices impacts the seller’s profitability when in fact the valuations are dependent, and find that this gap in profitability, which we call the “price of independence”, can be arbitrarily large.

Patient-Reported Outcome Measures and Risk Factors in a Quality Registry: A Basis for More Patient-Centered Diabetes Care in Sweden

Diabetes is one of the chronic diseases that constitute the greatest disease burden in the world. The Swedish National Diabetes Register is an essential part of the diabetes care system. Currently it mainly records clinical outcomes, but here we describe how it has started to collect patient-reported outcome measures, complementing the standard registry data on clinical outcomes as a basis for evaluating diabetes care. Our aims were to develop a questionnaire to measure patient abilities and judgments of their experience of diabetes care, to describe a Swedish diabetes patient sample in terms of their abilities, judgments, and risk factors, and to characterize groups of patients with a need for improvement. Patient abilities and judgments were estimated using item response theory. Analyzing them together with standard risk factors for diabetes comorbidities showed that the different types of data describe different aspects of a patient’s situation. These aspects occasionally overlap, but not in any particularly useful way. They both provide important information to decision makers, and neither is necessarily more relevant than the other. Both should therefore be considered, to achieve a more complete evaluation of diabetes care and to promote person-centered care.

Measuring Worksite Health Promotion Programs: an application of Structural Equation Modeling with ordinal data

This paper presents a model for measuring the outcome of Worksite Health Promotion Programs through an application of Structural Equation Modeling with ordinal data. We model the function “being healthy” as a vector comprised of three latent or unobservable variables: Health Status, Lifestyle and Stress. Each variable can be measured only indirectly through a set of manifest or observable ordinal indicators. The objective is to derive and analyze the distributions, and changes in distributions over time, of the latent variables on an individual level. The model is analyzed empirically on data from three large Swedish manufacturing firms.

Health-based pharmaceutical pay-for-performance risk-sharing agreements

Many new drugs, such as biologics and cancer drugs, are very costly. However, their effectiveness outside of clinical trial settings is often uncertain at the time they gain market approval. This uncertainty may reflect a lack of real-world outcomes data, as opposed to clinical trials data, for a typical patient population. A risk-sharing agreement is a contract between a drug manufacturer and a healthcare payer to help manage uncertainties regarding the cost and effectiveness of those drugs. In this paper, we model a risk-sharing agreement in which a proportion of total sales is rebated. We model disease progression using a continuous time Markov chain with uncertain transition rates. We examine the performance of this risk-sharing agreement from the manufacturer’s perspective and investigate the conditions under which the manufacturer will make a profit. We illustrate with a numerical model parameterized using data from a Phase 2 clinical trial of an oncology drug that was subjected to a risk-sharing agreement in the UK.

All-Pay Auctions with Pre- and Post-Bidding Options

Motivated by the emergence of online penny or pay-to-bid auctions, in this study, we analyze the operational consequences of all-pay auctions competing with fixed list price stores. In all-pay auctions, bidders place bids, and highest bidder wins. Depending on the auction format, the winner pays either the amount of their bid or that of the second-highest bid. All losing bidders forfeit their bids, regardless of the auction format. Bidders may visit the store, both before and after bidding, and buy the item at the fixed list price. In a modified version, we consider a setting where bidders can use their sunk bid as a credit towards buying the item from the auctioneer at a fixed price (different from the list price). We characterize a symmetric equilibrium in the bidding/buying strategy and derive optimal list prices for both the seller and auctioneer to maximize expected revenue. We consider two situations: (1) one firm operating both channels (i.e. fixed list price store and all-pay auction), and (2) two competing firms, each operating one of the two channels.

Customer Revenue Sharing Program in Online Social Media

Online social media (OSMs) have become a popular and growing phenomenon on the Internet, as exemplified by the millions of followers of websites like YouTube, Twitter and Facebook. Given the ease of access and high competition over the Internet to attract users, a question that arises is whether OSMs should develop revenue sharing programs and reward their contributing users. Aiming to expand market share and boost revenue, some OSMs recently have realized the influence of these programs in changing the outcome of their online competition. We model this competition by a duopoly game where users are either active or passive with respect to each OSM. We assume the OSMs are generally asymmetric, in that online users have a general preference for one. The game includes two steps: first, the OSMs simultaneously announce their rewards for active users, and second, users choose their level of contribution with respect to each OSM based on their preference. We show this game has a unique Nash equilibrium in pure strategies and specify how OSMs can derive the optimal reward payments. Our results include that, at equilibrium, no user will choose to contribute content exclusively to the less attractive OSM. In addition, we find that the more favourable OSM always receives a higher profit, even when it shares a lower reward. Based on numerical analysis, in most cases, the more favourable OSM shares a higher (lower) reward than the less favourable one, when the impact of active users’ contribution on OSMs revenue is small (high). Furthermore, we identify the conditions under which symmetric equilibrium exists despite the asymmetry between the OSMs.