A review and validation of overall survival extrapolation in health technology assessments of cancer immunotherapy by the National Institute for Health and Care Excellence: how did the initial best estimate compare to trial data subsequently made available?

Background: Validation of overall survival (OS) extrapolations of immune-checkpoint inhibitors (ICIs) during the National Institute for Health and Care Excellence (NICE) Single Technology Assessment (STA) process is limited due to data still maturing at the time of submission. Inaccurate extrapolation may lead to inappropriate decision-making. The availability of more mature trial data facilitates a retrospective analysis of the plausibility and validity of initial extrapolations. This study compares these extrapolations to subsequently available longer-term data.

Methods: A systematic search of completed NICE appraisals of ICIs from March 2000 to December 2017 was performed. A targeted search was also undertaken to procure published OS data from the pivotal clinical trials for each identified STA made available post-submission to NICE. Initial Kaplan-Meier curves and associated extrapolations from NICE documentation were extracted to compare the accuracy of OS projections versus the most mature data.

Results: The review identified 11 STAs, of which 10 provided OS data upon submission to NICE. The extrapolations undertaken considered parametric or piecewise survival models. Additional data cut-offs provided a mean of 18 months of OS beyond the end of the original data. Initial extrapolations typically under-estimated OS from the most mature data cut-off by 0.4–2.7%, depending on the choice of assessment method and use of the manufacturer- or ERG-preferred extrapolation.

Conclusion: Long-term extrapolation of OS is required for NICE STAs based on initial immature OS data. The results of this study demonstrate that the initial OS extrapolations employed by manufacturers and ERGs generally predicted OS reasonably well when compared to more mature data (when available), although on average they appeared to underestimate OS. This review and validation shows that, while the choice of OS extrapolation is uncertain, the methods adopted are generally aligned with later-published follow-up data and appear appropriate for informing HTA decisions.     

The Lifetime Distributional Impact of Government Health Outlays

This article examines the lifetime redistributive impact of government health outlays and finds that such outlays redistribute income from the lifetime rich to the lifetime poor and from men to women.     

The Distributional Impact of Selected Commonwealth Outlays and Taxes and Alternative Commonwealth Grant Allocation Mechanisms

This article examines the redistributive impact of Commonwealth outlays and taxes (including outlays directed through and to the States)and two possible alternative systems of distributing Commonwealth funding amongst the States.     

Estimating Bargaining Effects in Hedonic Models: Evidence from the Housing Market

Bargaining is common in markets for heterogeneous goods and differences in bargaining power between buyer and seller affect the negotiated transaction price. Previous research has found systematic evidence in the housing markets that weak buyers pay higher prices and weak sellers receive lower prices for their homes. Earlier work has modeled the bargaining effect as a parallel shift in the hedonic function, implicitly assuming that attribute shadow prices were unaffected by the bargaining process. In this paper, we use a sample of home sales where the seller's bargaining power is weakened by the fact that the home is vacant at the time of sale to test whether the effect of bargaining is best captured by a shift in the hedonic constant or whether the attribute shadow prices vary as well. The question is significant for property valuation where estimation of the marginal value of an attribute is commonly used to adjust comparable sales data. We find strong confirmation that bargaining power influences the negotiated price. We also find evidence that bargaining power alters attribute prices, although we do not find a consistent pattern across markets.     

A Bayesian Semiparametric Competing Risk Model with Unobserved Heterogeneity

This paper generalizes existing econometric models for censored competing risks by introducing a new flexible specification based on a piecewise linear baseline hazard, time‐varying regressors, and unobserved individual heterogeneity distributed as an infinite mixture of generalized inverse Gaussian (GIG) densities, nesting the gamma kernel as a special case. A common correlated latent time effect induces dependence among risks. Our model is based on underlying latent exit decisions in continuous time while only a time interval containing the exit time is observed, as is common in economic data. We do not make the simplifying assumption of discretizing exit decisions—our competing risk model setup allows for latent exit times of different risk types to be realized within the same time period. In this setting, we derive a tractable likelihood based on scaled GIG Laplace transforms and their higher‐order derivatives. We apply our approach to analyzing the determinants of unemployment duration with exits to jobs in the same industry or a different industry among unemployment insurance recipients on nationally representative individual‐level survey data from the US Department of Labor. Our approach allows us to conduct a counterfactual policy experiment by changing the replacement rate: we find that the impact of its change on the probability of exit from unemployment is inelastic. Copyright © 2014 John Wiley & Sons, Ltd.     

Building deals on bedrock

The headlines are filled with the sorry tales of companies like Vivendi and AOL Time Warner that tried to use mergers and acquisitions to grow big fast or transform fundamentally weak business models. But, drawing on extensive data and experience, the authors conclude that major deals make sense in only two circumstances: when they reinforce a company's existing basis of competition or when they help a company make the shift, as the industry's competitive base changes. In most stable industries, the authors contend, only one basis--superior cost position, brand power, consumer loyalty, real-asset advantage, or government protection--leads to industry leadership, and companies should do only those deals that bolster a strategy to capitalize on that competitive base. That's what Kellogg did when it acquired Keebler. Rather than bow to price pressures from lesser players, Kellogg sought to strengthen its existing basis of competition--its brand--through Keebler's innovative distribution system. A company coping with a changing industry should embark on a series of acquisitions (most likely coupled with divestitures) aimed at moving the firm to the new competitive basis. That's what Comcast did when changes in government regulations fundamentally altered the broadcast industry. In such cases, speed is essential, the investments required are huge, and half-measures can be worse than nothing at all. Still, the research shows, successful acquirers are not those that try to swallow a single, large, supposedly transformative deal but those that go to the M&A table often and take small bites. Deals can fuel growth--as long as they're anchored in the fundamental way money is made in your industry. Fail to understand that and no amount of integration planning will keep you and your shareholders from bearing the high cost of your mistakes.     

A quantile regression approach for estimating panel data models using instrumental variables

We introduce a quantile regression approach to panel data models with endogenous variables and individual effects correlated with the independent variables. We find newly developed quantile regression methods can be easily adapted to estimate this class of models efficiently.     

Designing automatic resupply systems.

This article outlines the process for designing and implementing autoresupply systems. The planning process includes determination of goals and appropriate participation. Different types of autoresupply mechanisms include kanban, breadman, consignment, systems contracts, and direct shipping from an MRP schedule.