Chris Sampson’s journal round-up for 5th August 2019

Every Monday our authors provide a round-up of some of the most recently published peer reviewed articles from the field. We don’t cover everything, or even what’s most important – just a few papers that have interested the author. Visit our Resources page for links to more journals or follow the HealthEconBot. If you’d like to write one of our weekly journal round-ups, get in touch.

The barriers and facilitators to model replication within health economics. Value in Health Published 16th July 2019

Replication is a valuable part of the scientific process, especially if there are uncertainties about the validity of research methods. When it comes to cost-effectiveness modelling, there are endless opportunities for researchers to do things badly, even with the best intentions. Attempting to replicate modelling studies can therefore support health care decision-making. But replication studies are rarely conducted, or, at least, rarely reported. The authors of this study sought to understand the factors that can make replication easy or difficult, with a view to informing reporting standards.

The authors attempted to replicate five published cost-effectiveness modelling studies, with the aim of recreating the key results. Each replication attempt was conducted by a different author and we’re even given a rating of the replicator’s experience level. The characteristics of the models were recorded and each replicator detailed – anecdotally – the things that helped or hindered their attempt. Some replications were a resounding failure. In one case, the replicated cost per patient was more than double the original, at more than £1,000 wide of the mark. Replicators reported that having a clear diagram of the model structure was a big help, as was the provision of example calculations and explicit listing of the key assumptions. Various shortcomings made replication difficult, all relating to a lack of clarity or completeness in reporting. The impact of this on the validation attempt was exacerbated if the model either involved lots of scenarios that weren’t clearly described or if the model had a long time horizon.

The quality of each study was assessed using the Philips checklist, and all did pretty well, suggesting that the checklist is not sufficient for ensuring replicability. If you develop and report cost-effectiveness models, this paper could help you better understand how end-users will interpret your reporting and make your work more replicable. This study focusses on Markov models. They’re definitely the most common approach, so perhaps that’s OK. It might be useful to produce prescriptive guidance specific to Markov models, informed by the findings of this study.

US integrated delivery networks perspective on economic burden of patients with treatment-resistant depression: a retrospective matched-cohort study. PharmacoEconomics – Open [PubMed] Published 28th June 2019

Treatment-resistant depression can be associated high health care costs, as multiple lines of treatment are tried, with patients experiencing little or no benefit. New treatments and models of care can go some way to addressing these challenges. In the US, there’s some reason to believe that integrated delivery networks (IDNs) could be associated with lower care costs, because IDNs are based on collaborative care models and constitute a single point of accountability for patient costs. They might be particularly useful in the case of treatment-resistant depression, but evidence is lacking. The authors of this study investigated the difference in health care resource use and costs for patients with and without treatment-resistant depression, in the context of IDNs.

The researchers conducted a retrospective cohort study using claims data for people receiving care from IDNs, with up to two years follow-up from first antidepressant use. 1,582 people with treatment-resistant depression were propensity score matched to two other groups – patients without depression and patients with depression that was not classified as treatment-resistant. Various regression models were used to compare the key outcomes of all-cause and specific categories of resource use and costs. Unfortunately, there is no assessment of whether the selected models are actually any good at estimating differences in costs.

The average costs and resource use levels in the three groups ranked as you would expect: $25,807 per person per year for the treatment-resistant group versus $13,701 in the non-resistant group and $8,500 in the non-depression group. People with treatment-resistant depression used a wider range of antidepressants and for a longer duration. They also had twice as many inpatient visits as people with depression that wasn’t treatment-resistant, which seems to have been the main driver of the adjusted differences in costs.

We don’t know (from this study) whether or not IDNs provide a higher quality of care. And the study isn’t able to compare IDN and non-IDN models of care. But it does show that IDNs probably aren’t a full solution to the high costs of treatment-resistant depression.

Rabin’s paradox for health outcomes. Health Economics [PubMed] [RePEc] Published 19th June 2019

Rabin’s paradox arises from the theoretical demonstration that a risk-averse individual who turns down a 50:50 gamble of gaining £110 or losing £100 would, if expected utility theory is correct, turn down a 50:50 gamble of losing £1,000 or gaining millions. This is because of the assumed concave utility function over wealth that is used to model risk aversion and it is probably not realistic. But we don’t know about the relevance of this paradox in the health domain… until now.

A key contribution of this paper is that it considers both decision-making about one’s own health and decision-making from a societal perspective. Three different scenarios are set-up in each case, relating to gains and losses in life expectancy with different levels of health functioning. 201 students were recruited as part of a larger study on preferences and each completed all six gamble-pairs (three individual, three societal). To test for Rabin’s paradox, the participants were asked whether they would accept each gamble involving a moderate stake and a large stake.

In short, the authors observe Rabin’s proposed failure of expected utility theory. Many participants rejected small gambles but did not reject the larger gambles. The effect was more pronounced for societal preferences. Though there was a large minority for whom expected utility theory was not violated. The upshot of all this is that our models of health preferences that are based on expected utility may be flawed where uncertain outcomes are involved – as they often are in health. This study adds to a growing body of literature supporting the relevance of alternative utility theories, such as prospect theory, to health and health care.

My only problem here is that life expectancy is not health. Life expectancy is everything. It incorporates the monetary domain, which this study did not want to consider, as well as every other domain of life. When you die, your stock of cash is as useful to you as your stock of health. I think it would have been more useful if the study focussed only on health status and outcomes and excluded all considerations of death.

Credits

Thesis Thursday: Feng-An Yang

On the third Thursday of every month, we speak to a recent graduate about their thesis and their studies. This month’s guest is Dr Feng-An Yang who has a PhD from Ohio State University. If you would like to suggest a candidate for an upcoming Thesis Thursday, get in touch.

Title
Three essays on access to health care in rural areas
Supervisors
Daeho Kim, Joyce Chen
Repository link
http://rave.ohiolink.edu/etdc/view?acc_num=osu152353045188255

What are the policy challenges for rural hospitals in the US?

Rural hospitals have been financially vulnerable, especially after the implementation of Medicare Prospective Payment System (PPS) in 1983, under which hospitals receive a predetermined, fixed reimbursement for their inpatient services. Under the PPS, they suffer from financial losses as their costs tend to exceed the reimbursement rate due to their smaller size and lower patient volume than their urban counterparts (Medicare Payment Advisory Commission, 2001 [PDF]). As a result, a noticeable number of rural hospitals have closed since the implementation of PPS (Congressional Budget Office, 1991 [PDF]).

This closure trend has slowed down thanks to public payment policies such as the Critical Access Hospitals (CAH) program, but rural hospitals are continuing to close their doors and a total of 107 rural hospitals have closed from 2010 to present according to the North Carolina Rural Health Research Program. This issue has raised public concern for rural residents’ access to health services and health status, and how to keep rural hospitals open has become an important policy priority.

Which data sources and models did you use to identify key events?

My dissertation investigated the impact of the CAH program and hospital closure by compiling data from various sources. The primary data come from the Medicare cost report, which contains detailed financial statements for nearly every U.S. hospital. Historical data on health care utilization at the county-level are obtained from the Area Health Resource File. County-level mortality rates are calculated from the national mortality files. Lastly, the list of CAHs and closed hospitals is obtained from the Flex Monitoring Team and American Hospital Association Annual Survey, respectively. This list contains information on the hospital identifier and year of event which is key to my empirical strategy.

To identify the impact of key events (i.e., CAH conversion and hospital closure), I use an event-study approach exploiting the variation in the timing of events. This approach estimates the changes in outcome for the time relative to the ‘event time’. A primary advantage of this approach is that it allows a visual examination of the evolution of changes in outcome before and after the event.

How can policies relating to rural hospitals benefit patients?

This question is not trivial because public payment policies are not directly linked to patients. The primary objective of these policies is to strengthen rural hospitals’ financial viability by providing them with enhanced reimbursement. As a result, it has been expected that, under these policies, rural hospitals will improve their financial conditions and stay open, thereby maintaining the access to health services for rural residents. Broadly speaking, public payment policies can lead to an increase in accessibility if we compare patient access to health services between counties with at least one hospital receiving financial support and counties without any hospitals receiving financial support.

I look at patient benefits from three aspects: accessibility, health care utilization, and mortality. My research shows that the CAH program has substantially improved CAHs’ financial conditions and as a result, some CAHs that otherwise would have been closed have stayed open. This in turn leads to an increase in rural residents’ access to and use of health services. We then provide suggestive evidence that the increased access to and use of health care services have improved patient health in rural areas.

Did you find any evidence that policies could have negative or unexpected consequences?

Certainly. The second chapter of my dissertation focused on skilled nursing care which can be provided in either swing beds (inpatient beds that can be used interchangeably for inpatient care or skilled nursing care) or hospital-based skilled nursing facilities (SNFs). Since the services provided in swing beds and SNFs are equivalent, differential payments, if present, may encourage hospitals to use one over the other.

While the CAH program provides enhanced reimbursement to rural hospitals, it also changes the swing bed reimbursement method such that swing bed payments are more favorable than SNF payments. As a result, CAHs may have a financial incentive to increase the use of swing beds over SNFs. By focusing on CAHs with a SNF, my research shows a remarkable increase in swing bed utilization and this increase is fully offset by the decrease in SNF utilization. These results suggest that CAHs substitute swing beds for SNFs in response to the change in swing bed reimbursement method.

Based on your research, what would be your key recommendations for policymakers?

Based on my research findings, I would make two recommendations for policymakers.

First, my research speaks to the ongoing debate over the elimination of CAH designation for certain hospitals. Loss of CAH designation could have serious financial consequences and subsequently have potentially adverse impacts on patient access to and use of health care. Therefore, I would recommend policymakers to maintain the CAH designation.

Second, while the CAH program has improved rural hospitals’ financial conditions, it has also created a financial incentive for hospitals to use the service with a higher reimbursement rate. Thus, my recommendation to policymakers would be to consider potentially substitutable health care services when designing reimbursement rates.

Thesis Thursday: Rebecca Addo

On the third Thursday of every month, we speak to a recent graduate about their thesis and their studies. This month’s guest is Dr Rebecca Addo who has a PhD from the University of Technology Sydney. If you would like to suggest a candidate for an upcoming Thesis Thursday, get in touch.

Title
The feasibility of health technology assessment (HTA) in the Ghanaian health system
Supervisors
Jane Hall, Stephen Goodall, Marion Haas
Repository link
http://hdl.handle.net/10453/133353

Why is now the right time to research the feasibility of HTA in Ghana?

In recent years, Ghana has been struggling to financially sustain the National Health Insurance Scheme (NHIS), through which it aims to attain universal health coverage (UHC). As a result, a number of payment methods have been explored, including capitation, but costs to the NHIS continue to escalate. The search for a more efficient NHIS funding resulted in stakeholders visiting the then NICE International, learnt of HTA, and expressed an interest in pursuing it. This interest was strengthened by the World Health Organization 2014 resolution, which encouraged its member states to adopt health interventions and technology assessments in support of UHC. In 2016, a pilot HTA study was conducted with support from international bodies that demonstrated potential cost savings with HTA. Subsequently, the Ghana National Medicines Policy, 2017, made provisions for the use of HTA in the selection of medicines. What remains uncertain is how the policy will be implemented, considering that the limited use of HTA in developing countries has been attributed to a lack of human capacity to undertake it, quality data, and limited resources to support it. With Ghana making progress towards the formal adoption of HTA for health decision-making, it is important to examine its feasibility considering the available national capacity and the health system’s particular characteristics, and to make recommendations on how Ghana can proceed, so that the anticipated positive changes can be realised.

What determines ‘feasibility’ in this context?

The usefulness of HTA to any health system is highly dependent on its availability, the quality of assessment, and the human capacity to conduct country specific appraisals. Thus ‘feasibility’ in this context is determined by the existing health resources and systems that could support the adoption and use of HTA in Ghana. Health resources include human capacity with the needed technical skills to conduct and contribute to HTA, funding for the HTA processes, and the available data, which is of good quality and easily accessible. In addition, potential users of HTA should have knowledge in HTA and be able to interpret its findings. Without these building blocks, HTA in itself cannot be successfully used in Ghana. The systems to consider are health system characteristics such as existing health decision-making processes, and political and social structures. Knowledge of this would aid with planning, design, and introduction of an HTA process that suits the Ghanaian health system’s decision-making context, which would promote its use.

How is HTA perceived by stakeholders in Ghana?

Whilst the majority of Ghanaian stakeholders who participated in my study understood HTA as a decision making tool, others saw it as using technologies such as telemedicine and mobile phone devices for healthcare delivery. Their prior understanding of HTA and its uses drove these differences. In terms of its potential use in the Ghanaian health system, most stakeholders acknowledged the benefits the health system stood to gain should HTA be adopted. They however perceived some barriers to the successful implementation of HTA and made some recommendations to address them. Perceived barriers included lack of knowledge of HTA by potential users, lack of human resource capacity to conduct it, lack of funds to support the conduct, and existing ways of making decisions. Factors perceived to promote HTA use were allocating funds for HTA activities, educating stakeholders on HTA and involving them in the planning, and introduction of HTA for health decision-making in Ghana. Also, stakeholders recommended that data be collated and managed for HTA, and for local Ghanaians to be trained to conduct HTA but rely on experts from other countries where possible.

Was it especially challenging to conduct an economic evaluation in the Ghanaian context?

Yes. Conducting a Ghanaian specific economic evaluation was very challenging, especially, in getting the appropriate data. There were no country-specific utility and clinical efficacy data, hence, I had to rely on data from elsewhere, which needed to the transformed to be context specific. The most challenging aspect was with getting appropriate clinical data due to the differences between clinical trial settings and the Ghanaian setting. Applicability issues that were addressed included differences in clinical treatment algorithm, alternative treatments, and epidemiology of disease. Cultural acceptance of available treatment for the study population also defined the appropriate comparator for the evaluation and consequently the clinical data that could be considered. This resulted in having to draw on data from two separate arms of two clinical trials for one of the models I built for my economic evaluation. To ensure applicability of data from other countries to Ghana, the data identified were transformed to be context specific with data input from Ghana either not available or not easily accessible. Therefore, clinical experts were relied upon for such inputs, adding to the limitations of the economic evaluation.

Can HTA processes from other countries be applied in Ghana?

Every health system is unique in its entirety, therefore processes used in one cannot be adopted and applied to the other. The same applies to HTA in Ghana. As part of my thesis, I reviewed a number of HTA organisations across the world to assess if one could be adopted in Ghana. The review revealed that HTA processes vary with each health system in terms of the context under which they were established, the scope or focus of HTA, outcomes, and links to funding decisions and their uses. The establishment of most of these HTA organisations was driven by country specific needs such as curbing the rising costs of healthcare and reducing variations in the availability of quality treatment and care. The available resources, such as human and data, and the health systems characteristics also influenced the HTA processes. Therefore it is not advisable for Ghana to simply adopt and use a model of HTA process from other countries. Rather, Ghana must pursue a country specific HTA process that is informed by relevant country data.

What would be your recommended ‘next step’ for HTA in Ghana?

Firstly, to ensure the acceptance, use and diffusion of HTA in Ghana, stakeholders of health should be educated on HTA and a legal framework stipulating its focus and conduct, and mandating its use, to be adopted.

Secondly, in the short-to-medium term, Ghana can leverage on ongoing collaborations with other countries and foreign organisations, such as the International Decision Support initiative (IDSi), to develop local capacity for HTA. In the long-term, it will be necessary for policy makers to explore the human resource capacity available for HTA in Ghana to guide the development of a human resource plan for HTA.

Thirdly, Ghana has to develop a country-specific methodological guideline or adapt an existing one for the conduct and reporting of economic evaluation studies in Ghana. Subsequently, guidelines for conducting HTA should be developed.

Lastly, to support HTA conduct, Ghana must create a national data repository including a manual on health resource use and their corresponding unit prices. The creation of an HTA standing panel of clinical experts and other stakeholders who could be relied upon to supply inputs for HTA when needed is also recommended. This is very important in the Ghanaian setting where availability and access to data is limited.