Assessing cost-effectiveness in obesity (ACE-Obesity) : an overview of the ACE approach, economic methods and cost results

Background : The aim of the ACE-Obesity study was to determine the economic credentials of interventions which aim to prevent unhealthy weight gain in children and adolescents. We have reported elsewhere on the modelled effectiveness of 13 obesity prevention interventions in children. In this paper, we report on the cost results and associated methods together with the innovative approach to priority setting that underpins the ACE-Obesity study.

Methods : The Assessing Cost-Effectiveness (ACE) approach combines technical rigour with 'due process' to facilitate evidence-based policy analysis. Technical rigour was achieved through use of standardised evaluation methods, a research team that assembles best available evidence and extensive uncertainty analysis. Cost estimates were based on pathway analysis, with resource usage estimated for the interventions and their 'current practice' comparator, as well as associated cost offsets. Due process was achieved through involvement of stakeholders, consensus decisions informed by briefing papers and 2nd stage filter analysis that captures broader factors that influence policy judgements in addition to cost-effectiveness results. The 2nd stage filters agreed by stakeholders were 'equity', 'strength of the evidence', 'feasibility of implementation', 'acceptability to stakeholders', 'sustainability' and 'potential for side-effects'.

Results : The intervention costs varied considerably, both in absolute terms (from cost saving [6 interventions] to in excess of AUD50m per annum) and when expressed as a 'cost per child' estimate (from <AUD1.0 [reduction of TV advertising of high fat foods/high sugar drinks] to >AUD31,000 [laparoscopic adjustable gastric banding for morbidly obese adolescents]). High costs per child reflected cost structure, target population and/or under-utilisation.

Conclusions : The use of consistent methods enables valid comparison of potential intervention costs and cost-offsets for each of the interventions. ACE-Obesity informs policy-makers about cost-effectiveness, health impact, affordability and 2nd stage filters for important options for preventing unhealthy weight gain in children. In related articles cost-effectiveness results and second stage filter considerations for each intervention assessed will be presented and analysed.

The cost-effectiveness of removing television advertising of high-fat and/or high-sugar food and beverages to Australian children

Objective: To model the health benefits and cost-effectiveness of banning television (TV) advertisements in Australia for energy-dense, nutrient-poor food and beverages during children's peak viewing times.

Methods: Benefits were modelled as changes in body mass index (BMI) and disability-adjusted life years (DALYs) saved. Intervention costs (AUD$) were compared with future health-care cost offsets from reduced prevalence of obesity-related health conditions. Changes in BMI were assumed to be maintained through to adulthood. The comparator was current practice, the reference year was 2001, and the discount rate for costs and benefits was 3%. The impact of the withdrawal of non-core food and beverage advertisements on children's actual food consumption was drawn from the best available evidence (a randomized controlled trial of advertisement exposure and food consumption). Supporting evidence was found in ecological relationships between TV advertising and childhood obesity, and from the effects of marketing bans on other products. A Working Group of stakeholders provided input into decisions surrounding the modelling assumptions and second-stage filters of 'strength of evidence', 'equity', 'acceptability to stakeholders', 'feasibility of implementation', 'sustainability' and 'side-effects'.

Results: The intervention had a gross incremental cost-effectiveness ratio of AUD$ 3.70 (95% uncertainty interval (UI) $2.40, $7.70) per DALY. Total DALYs saved were 37 000 (95% UI 16 000, 59 000). When the present value of potential savings in future health-care costs was considered (AUD$ 300m (95% UI $130m, $480m), the intervention was 'dominant', because it resulted in both a health gain and a cost offset compared with current practice.

Conclusions: Although recognizing the limitations of the available evidence, restricting TV food advertising to children would be one of the most cost-effective population-based interventions available to governments today. Despite its economic credentials from a public health perspective, the initiative is strongly opposed by food and advertising industries and is under review by the current Australian government.

Assessing cost-effectiveness in mental health: helping policy-makers prioritize and plan health services

Objective: We assessed, from a health sector perspective, options for change that could improve the efficiency of Australia's current mental health services by directing available resources toward 'best practice' cost-effective services.

Method: We summarize cost-effectiveness results of a range of interventions for depression, schizophrenia, attention deficit hyperactivity disorder and anxiety disorders that have been presented in previous papers in this journal. Recommendations for change are formulated after taking into account 'second-filter criteria' of equity, feasibility of implementing change, acceptability to stakeholders and the strength of the evidence. In addition, we estimate the impact on total expenditure if the recommended mental health interventions for depression and schizophrenia are to be implemented in Australia.

Results: There are cost-effective treatment options for mental disorders that are currently underutilized (e.g. cognitive–behavioural therapy (CBT) for depression and anxiety, bibliotherapy for depression, family interventions for schizophrenia and clozapine for the worst course of schizophrenia). There are also less cost-effective treatments in current practice (e.g. widespread use of olanzapine and risperidone in the treatment of established schizophrenia and, within those atypicals, a preference for olanzapine over risperidone). Feasibility of funding mechanisms and training of staff are the main second-filter issues for CBT and family interventions. Acceptability to various stakeholders is the main barrier to implementation of more cost-effective drug treatment regimens. More efficient drug intervention options identified for schizophrenia would cost A$68 million less than current practice. These savings would more than cover the estimated A$36M annual cost of delivering family interventions to the 51% of people with schizophrenia whom we estimated to be eligible and this would lead to an estimated 12% improvement in their health status. Implementing recommended strategies for depression would cost A$121M annually for the 24% of people with depression who seek care currently, but do not receive an evidence-based treatment.

Conclusions: Despite considerable methodological problems, a range of cost-effective and less cost-effective interventions for major mental disorders can be discerned. The biggest hurdle to implementation of more efficient mental health services is that this change would require reallocation of funds between interventions, between disorders and between service providers with different funding mechanisms.