Response bias shows up in many fields of behavioural and healthcare research where self-reported data are used. We demonstrate how to use stochastic frontier estimation (SFE) to identify response bias and its covariates. In our application to a family intervention, we examine the effects of participant demographics on response bias before and after participation; gender and race/ethnicity are related to magnitude of bias and to changes in bias across time, and bias is lower at post-test than at pre-test. We discuss how SFE may be used to address the problem of ‘response shift bias’ – that is, a shift in metric from before to after an intervention which is caused by the intervention itself and may lead to underestimates of programme effects.

This study documents for the first time the extraordinary costs to take care of patients with a chronic, non-fatal, relatively rare disorder who have been incorrectly thought to have an insignificant and self-limiting illness. Idiopathic intracranial hypertension (IIH) occurs worldwide and in all racial groups and is found predominantly in obese women (∼ 90%) of childbearing age. Although the incidence of IIH is increasing as a result of the rapid increase in obesity, the disorder in general receives little recognition, and no recognition of the extensive burden of healthcare costs placed on patients, their families and society. We established for the first time both the prevalence of IIH in the USA and the direct and indirect costs of IIH using a prevalence-based model. IIH patients had an exceptionally high hospital admission rate of 38% (in 2007), a partial reflection of unsatisfactory treatment options. The total hospital costs per IIH admission in 2007 were four times greater than for a population-based per person admission. Total economic costs of IIH patients exceeded $444 million. Programmes designed to reduce obesity prior to and after diagnosis and better therapeutics will have a tremendous economic impact.

We analyze marijuana use by college undergraduates before and after legalization of recreational marijuana. Using survey data from the National College Health Assessment, we show that students at Washington State University experienced a significant increase in marijuana use after legalization. This increase is larger than would be predicted by national trends. The change is strongest among females, Black students, and Hispanic students. The increase for underage students is as much as for legal-age students. We find no corresponding changes in the consumption of tobacco, alcohol, or other drugs.

This paper estimates a long-run hospital cost function with multiple outputs and inputs using a panel data set from Washington State hospitals during 1988-1993. We find that with our data the generalized Leontief function is more appropriate than a translog for estimating hospital cost functions. With respect to hospital costs, we find that hospitals readily adjust the use of intermediate products. Radiology, therapies and surgery, and other inpatient days, all serve as substitutes for core inpatient days. Outpatient services are found to be complementary to core inpatient services, indicating that the growth of stand-alone outpatient clinics might increase the costs of providing healthcare services. Our analysis finds that hospitals show significant economies of scale, but there is a limited amount of evidence of scope economies. Also, there is some evidence that profit-seeking hospitals achieve some of their goals by controlling costs, and that diagnostically related groups (DRG)-based Medicare services are effective in getting hospitals to control costs.

Using a national data set, this paper looks at the efficiency of physician practices, focusing on scopes of service by comparing single specialty groups and multispecialty groups. An analysis of efficiency using DEA indicates that there are scope inefficiencies from combining different types of providers into a single practice. Most of the inefficiency is due to technical rather than allocative reasons. In addition, we find that larger practices are able to capture efficiencies of scope, but incur inefficiencies of scale.