Prioritization of intervention domains to prevent cardiovascular disease: a country-level case study using global burden of disease and local data.

AIM: We aimed to combine Global Burden of Disease (GBD) Study data and local data to identify the highest priority intervention domains for preventing cardiovascular disease (CVD) in the case study country of Aotearoa New Zealand (NZ). METHODS: Risk factor data for CVD in NZ were extracted from the GBD using the "GBD Results Tool." We prioritized risk factor domains based on consideration of the size of the health burden (disability-adjusted life years [DALYs]) and then by the domain-specific interventions that delivered the highest health gains and cost-savings. RESULTS: Based on the size of the CVD health burden in DALYs, the five top prioritized risk factor domains were: high systolic blood pressure (84,800 DALYs; 5400 deaths in 2019), then dietary risk factors, then high LDL cholesterol, then high BMI and then tobacco (30,400 DALYs; 1400 deaths). But if policy-makers aimed to maximize health gain and cost-savings from specific interventions that have been studied, then they would favor the dietary risk domain (e.g., a combined fruit and vegetable subsidy plus a sugar tax produced estimated lifetime savings of 894,000 health-adjusted life years and health system cost-savings of US$11.0 billion; both 3% discount rate). Other potential considerations for prioritization included the potential for total health gain that includes non-CVD health loss and potential for achieving relatively greater per capita health gain for Maori (Indigenous) to reduce health inequities. CONCLUSIONS: We were able to show how CVD risk factor domains could be systematically prioritized using a mix of GBD and country-level data. Addressing high systolic blood pressure would be the top ranked domain if policy-makers focused just on the size of the health loss. But if policy-makers wished to maximize health gain and cost-savings using evaluated interventions, dietary interventions would be prioritized, e.g., food taxes and subsidies.

Impact of taxes on purchases of close substitute foods: analysis of cross-price elasticities using data from a randomized experiment.

OBJECTIVE: To examine the effects of health-related food taxes on substitution and complementary purchases within food groups, including from unhealthier to healthier alternatives and between brands. METHODS: We used data from a virtual supermarket experiment with data from 4,259 shopping events linked to varying price sets. Substitution or complementary effects within six frequently purchased food categories were analyzed. Products' own- and cross-price elasticities were analyzed using Almost Ideal Demand System models. RESULTS: Overall, 37.5% of cross-price elasticities were significant (p < 0.05) and included values greater than 0.10. Supplementary and complementary effects were particularly found in the dairy, meats and snacks categories. For example, a 1% increase in the price of high saturated fat dairy was associated with a 0.18% (SE 0.06%) increase in purchases of low saturated fat dairy. For name- and home-brand products, significant substitution effects were found in 50% (n = 3) of cases, but only in one case this was above the 0.10 threshold. CONCLUSIONS/POLICY IMPLICATIONS: Given the relatively low own-price elasticities and the limited substitution and complementary effects, relatively high taxes are needed to substantively increase healthy food purchases at the population level. TRIAL REGISTRATION: This study included secondary analyses; the original trial was registered in the Australian New Zealand Clinical Trials Registry ACTRN12616000122459 .

Health benefits and costs of weight-loss dietary counselling by nurses in primary care: a cost-effectiveness analysis.

OBJECTIVE: We aimed to estimate the cost-effectiveness of brief weight-loss counselling by dietitian-trained practice nurses, in a high-income-country case study. DESIGN: A literature search of the impact of dietary counselling on BMI was performed to source the 'best' effect size for use in modelling. This was combined with multiple other input parameters (e.g. epidemiological and cost parameters for obesity-related diseases, likely uptake of counselling) in an established multistate life-table model with fourteen parallel BMI-related disease life tables using a 3 % discount rate. SETTING: New Zealand (NZ). PARTICIPANTS: We calculated quality-adjusted life-years (QALY) gained and health-system costs over the remainder of the lifespan of the NZ population alive in 2011 (n 4·4 million). RESULTS: Counselling was estimated to result in an increase of 250 QALY (95 % uncertainty interval -70, 560 QALY) over the population's lifetime. The incremental cost-effectiveness ratio was 2011 $NZ 138 200 per QALY gained (2018 $US 102 700). Per capita QALY gains were higher for Maori (Indigenous population) than for non-Maori, but were still not cost-effective. If willingness-to-pay was set to the level of gross domestic product per capita per QALY gained (i.e. 2011 $NZ 45 000 or 2018 $US 33 400), the probability that the intervention would be cost-effective was 2 %. CONCLUSIONS: The study provides modelling-level evidence that brief dietary counselling for weight loss in primary care generates relatively small health gains at the population level and is unlikely to be cost-effective.

Can cost-effectiveness results be combined into a coherent league table? Case study from one high-income country.

BACKGROUND: Doubts exist around the value of compiling league tables for cost-effectiveness results for health interventions, primarily due to methods differences. We aimed to determine if a reasonably coherent league table could be compiled using published studies for one high-income country: New Zealand (NZ). METHODS: Literature searches were conducted to identify NZ-relevant studies published in the peer-reviewed journal literature between 1 January 2010 and 8 October 2017. Only studies with the following metrics were included: cost per quality-adjusted life-year or disability-adjusted life-year or life-year (QALY/DALY/LY). Key study features were abstracted and a summary league table produced which classified the studies in terms of cost-effectiveness. RESULTS: A total of 21 cost-effectiveness studies which met the inclusion criteria were identified. There were some large methodological differences between the studies, particularly in the time horizon (1 year to lifetime) but also discount rates (range 0 to 10%). Nevertheless, we were able to group the incremental cost-effectiveness ratios (ICERs) into general categories of being reported as cost-saving (19%), cost-effective (71%), and not cost-effective (10%). The median ICER (adjusted to 2017 NZ$) was ~ $5000 per QALY/DALY/LY (~US$3500). However, for some interventions, there is high uncertainty around the intervention effectiveness and declining adherence over time. CONCLUSIONS: It seemed possible to produce a reasonably coherent league table for the ICER values from different studies (within broad groupings) in this high-income country. Most interventions were cost-effective and a fifth were cost-saving. Nevertheless, study methodologies did vary widely and researchers need to pay more attention to using standardised methods that allow their results to be included in future league tables.

Mass media promotion of a smartphone smoking cessation app: modelled health and cost-saving impacts.

BACKGROUND: Smartphones are increasingly available and some high quality apps are available for smoking cessation. However, the cost-effectiveness of promoting such apps has never been studied. We therefore aimed to estimate the health gain, inequality impacts and cost-utility from a five-year promotion campaign of a smoking cessation smartphone app compared to business-as-usual (no app use for quitting). METHODS: A well-established Markov macro-simulation model utilising a multi-state life-table was adapted to the intervention (lifetime horizon, 3% discount rate). The setting was the New Zealand (NZ) population (N = 4.4 million). The intervention effect size was from a multi-country randomised trial: relative risk for quitting at 6 months = 2.23 (95%CI: 1.08 to 4.77), albeit subsequently adjusted to consider long-term relapse. Intervention costs were based on NZ mass media promotion data and the NZ cost of attracting a smoker to smoking cessation services (NZ$64 per person). RESULTS: The five-year intervention was estimated to generate 6760 QALYs (95%UI: 5420 to 8420) over the remaining lifetime of the population. For Maori (Indigenous population) there was 2.8 times the per capita age-standardised QALY gain relative to non-Maori. The intervention was also estimated to be cost-saving to the health system (saving NZ$115 million [m], 95%UI: 72.5m to 171m; US$81.8m). The cost-saving aspect of the intervention was maintained in scenario and sensitivity analyses where the discount rate was doubled to 6%, the effect size halved, and the intervention run for just 1 year. CONCLUSIONS: This study provides modelling-level evidence that mass-media promotion of a smartphone app for smoking cessation could generate health gain, reduce ethnic inequalities in health and save health system costs. Nevertheless, there are other tobacco control measures which generate considerably larger health gains and cost-savings such as raising tobacco taxes.

Impact of five tobacco endgame strategies on future smoking prevalence, population health and health system costs: two modelling studies to inform the tobacco endgame.

OBJECTIVE: There is growing international interest in advancing 'the tobacco endgame'. We use New Zealand (Smokefree goal for 2025) as a case study to model the impacts on smoking prevalence (SP), health gains (quality-adjusted life-years (QALYs)) and cost savings of (1) 10% annual tobacco tax increases, (2) a tobacco-free generation (TFG), (3) a substantial outlet reduction strategy, (4) a sinking lid on tobacco supply and (5) a combination of 1, 2 and 3. METHODS: Two models were used: (1) a dynamic population forecasting model for SP and (2) a closed cohort (population alive in 2011) multistate life table model (including 16 tobacco-related diseases) for health gains and costs. RESULTS: All selected tobacco endgame strategies were associated with reductions in SP by 2025, down from 34.7%/14.1% for Maori (indigenous population)/non-Maori in 2011 to 16.0%/6.8% for tax increases; 11.2%/5.6% for the TFG; 17.8%/7.3% for the outlet reduction; 0% for the sinking lid; and 9.3%/4.8% for the combined strategy. Major health gains accrued over the remainder of the 2011 population's lives ranging from 28 900 QALYs (95% Uncertainty Interval (UI)): 16 500 to 48 200; outlet reduction) to 282 000 QALYs (95%UI: 189 000 to 405 000; sinking lid) compared with business-as-usual (3% discounting). The timing of health gain and cost savings greatly differed for the various strategies (with accumulated health gain peaking in 2040 for the sinking lid and 2070 for the TFG). CONCLUSIONS: Implementing endgame strategies is needed to achieve tobacco endgame targets and reduce inequalities in smoking. Given such strategies are new, modelling studies provide provisional information on what approaches may be best.

A national quitline service and its promotion in the mass media: modelling the health gain, health equity and cost-utility.

BACKGROUND: Mass media campaigns and quitlines are both important distinct components of tobacco control programmes around the world. But when used as an integrated package, the effectiveness and cost-effectiveness are not well described. We therefore aimed to estimate the health gain, health equity impacts and cost-utility of the package of a national quitline service and its promotion in the mass media. METHODS: We adapted an established Markov and multistate life-table macro-simulation model. The population was all New Zealand adults in 2011. Effect sizes and intervention costs were based on past New Zealand quitline data. Health system costs were from a national data set linking individual health events to costs. RESULTS: The 1-year operation of the existing intervention package of mass media promotion and quitline service was found to be net cost saving to the health sector for all age groups, sexes and ethnic groups (saving $NZ84 million; 95%uncertainty interval 60-115 million in the base-case model). It also produced greater per capita health gains for Maori (indigenous) than non-Maori (2.2 vs 0.73 quality-adjusted life-years (QALYs) per 1000 population, respectively). The net cost saving of the intervention was maintained in all sensitivity and scenario analyses for example at a discount rate of 6% and when the intervention effect size was quartered (given the possibility of residual confounding in our estimates of smoking cessation). Running the intervention for 20 years would generate an estimated 54 000 QALYs and $NZ1.10 billion (US$0.74 billion) in cost savings. CONCLUSIONS: The package of a quitline service and its promotion in the mass media appears to be an effective means to generate health gain, address health inequalities and save health system costs. Nevertheless, the role of this intervention needs to be compared with other tobacco control and health sector interventions, some of which may be even more cost saving.

Impact of increasing tobacco taxes on working-age adults: short-term health gain, health equity and cost savings.

OBJECTIVE: The health gains and cost savings from tobacco tax increase peak many decades into the future. Policy-makers may take a shorter-term perspective and be particularly interested in the health of working-age adults (given their role in economic productivity). Therefore, we estimated the impact of tobacco taxes in this population within a 10-year horizon. METHODS: As per previous modelling work, we used a multistate life table model with 16 tobacco-related diseases in parallel, parameterised with rich national data by sex, age and ethnicity. The intervention modelled was 10% annual increases in tobacco tax from 2011 to 2020 in the New Zealand population (n=4.4 million in 2011). The perspective was that of the health system, and the discount rate used was 3%. RESULTS: For this 10-year time horizon, the total health gain from the tobacco tax in discounted quality-adjusted life years (QALYs) in the 20-65 year age group (age at QALY accrual) was 180 QALYs or 1.6% of the lifetime QALYs gained in this age group (11 300 QALYs). Nevertheless, for this short time horizon: (1) cost savings in this group amounted to NZ$10.6 million (equivalent to US$7.1 million; 95% uncertainty interval: NZ$6.0 million to NZ$17.7 million); and (2) around two-thirds of the QALY gains for all ages occurred in the 20-65 year age group. Focusing on just the preretirement and postretirement ages, the QALY gains in each of the 60-64 and 65-69 year olds were 11.5% and 10.6%, respectively, of the 268 total QALYs gained for all age groups in 2011-2020. CONCLUSIONS: The majority of the health benefit over a 10-year horizon from increasing tobacco taxes is accrued in the working-age population (20-65 years). There remains a need for more work on the associated productivity benefits of such health gains.

Correction: Health, Health Inequality, and Cost Impacts of Annual Increases in Tobacco Tax: Multistate Life Table Modeling in New Zealand.

[This corrects the article DOI: 10.1371/journal.pmed.1001856.].

Tobacco retail outlet restrictions: health and cost impacts from multistate life-table modelling in a national population.

BACKGROUND: Since there is some evidence that the density and distribution of tobacco retail outlets may influence smoking behaviours, we aimed to estimate the impacts of 4 tobacco outlet reduction interventions in a country with a smoke-free goal: New Zealand (NZ). METHODS: A multistate life-table model of 16 tobacco-related diseases, using national data by sex, age and ethnicity, was used to estimate quality-adjusted life years (QALYs) gained and net costs over the remainder of the 2011 NZ population's lifetime. The outlet reduction interventions assumed that increased travel costs can be operationalised as equivalent to price increases in tobacco. RESULTS: All 4 modelled interventions led to reductions of >89% of current tobacco outlets after the 10-year phase-in process. The most effective intervention limited sales to half of liquor stores (and nowhere else) at 129 000 QALYs gained over the lifetime of the population (95% UI: 74 100 to 212 000, undiscounted). The per capita QALY gains were up to 5 times greater for Maori (indigenous population) compared to non-Maori. All interventions were cost-saving to the health system, with the largest saving for the liquor store only intervention: US$1.23 billion (95% UI: $0.70 to $2.00 billion, undiscounted). CONCLUSIONS: These tobacco outlet reductions reduced smoking prevalence, achieved health gains and saved health system costs. Effects would be larger if outlet reductions have additional spill-over effects (eg, smoking denormalisation). While these interventions were not as effective as tobacco tax increases (using the same model), these and other strategies could be combined to maximise health gain and to maximise cost-savings to the health system.

Modeling health gains and cost savings for ten dietary salt reduction targets.

BACKGROUND: Dietary salt reduction is included in the top five priority actions for non-communicable disease control internationally. We therefore aimed to identify health gain and cost impacts of achieving a national target for sodium reduction, along with component targets in different food groups. METHODS: We used an established dietary sodium intervention model to study 10 interventions to achieve sodium reduction targets. The 2011 New Zealand (NZ) adult population (2.3 million aged 35+ years) was simulated over the remainder of their lifetime in a Markov model with a 3 % discount rate. RESULTS: Achieving an overall 35 % reduction in dietary salt intake via implementation of mandatory maximum levels of sodium in packaged foods along with reduced sodium from fast foods/restaurant food and discretionary intake (the "full target"), was estimated to gain 235,000 QALYs over the lifetime of the cohort (95 % uncertainty interval [UI]: 176,000 to 298,000). For specific target components the range was from 122,000 QALYs gained (for the packaged foods target) down to the snack foods target (6100 QALYs; and representing a 34-48 % sodium reduction in such products). All ten target interventions studied were cost-saving, with the greatest costs saved for the mandatory "full target" at NZ$1260 million (US$820 million). There were relatively greater health gains per adult for men and for Maori (indigenous population). CONCLUSIONS: This work provides modeling-level evidence that achieving dietary sodium reduction targets (including specific food category targets) could generate large health gains and cost savings for a national health sector. Demographic groups with the highest cardiovascular disease rates stand to gain most, assisting in reducing health inequalities between sex and ethnic groups.

The health gains and cost savings of dietary salt reduction interventions, with equity and age distributional aspects.

BACKGROUND: A "diet high in sodium" is the second most important dietary risk factor for health loss identified in the Global Burden of Disease Study 2013. We therefore aimed to model health gains and costs (savings) of salt reduction interventions related to salt substitution and maximum levels in bread, including by ethnicity and age. We also ranked these four interventions compared to eight other modelled interventions. METHODS: A Markov macro-simulation model was used to estimate QALYs gained and net health system costs for four dietary sodium reduction interventions, discounted at 3 % per annum. The setting was New Zealand (NZ) (2.3 million adults, aged 35+ years) which has detailed individual-level administrative cost data. RESULTS: The health gain was greatest for an intervention where most (59 %) of the sodium in processed foods was replaced by potassium and magnesium salts. This intervention gained 294,000 QALYs over the remaining lifetime of the cohort (95 % UI: 238,000 to 359,000; 0.13 QALY per 35+ year old). Such salt substitution also produced the highest net cost-savings of NZ$ 1.5 billion (US$ 1.0 billion) (95 % UI: NZ$ 1.1 to 2.0 billion). All interventions generated relatively larger per capita QALYs for men vs women and for the indigenous Maori population vs non-Maori (e.g., 0.16 vs 0.12 QALYs per adult for the 59 % salt substitution intervention). Of relevance to workforce productivity, in the first 10 years post-intervention, 22 % of the QALY gain was among those aged <65 years (and 37 % for those aged <70). CONCLUSIONS: The benefits are consistent with the international literature, with large health gains and cost savings possible from some, but not all, sodium reduction interventions. Health gain appears likely to occur among working-age adults and all interventions contributed to reducing health inequalities.

Study protocol: combining experimental methods, econometrics and simulation modelling to determine price elasticities for studying food taxes and subsidies (The Price ExaM Study).

BACKGROUND: There is a need for accurate and precise food price elasticities (PE, change in consumer demand in response to change in price) to better inform policy on health-related food taxes and subsidies. METHODS/DESIGN: The Price Experiment and Modelling (Price ExaM) study aims to: I) derive accurate and precise food PE values; II) quantify the impact of price changes on quantity and quality of discrete food group purchases and; III) model the potential health and disease impacts of a range of food taxes and subsidies. To achieve this, we will use a novel method that includes a randomised Virtual Supermarket experiment and econometric methods. Findings will be applied in simulation models to estimate population health impact (quality-adjusted life-years [QALYs]) using a multi-state life-table model. The study will consist of four sequential steps: 1. We generate 5000 price sets with random price variation for all 1412 Virtual Supermarket food and beverage products. Then we add systematic price variation for foods to simulate five taxes and subsidies: a fruit and vegetable subsidy and taxes on sugar, saturated fat, salt, and sugar-sweetened beverages. 2. Using an experimental design, 1000 adult New Zealand shoppers complete five household grocery shops in the Virtual Supermarket where they are randomly assigned to one of the 5000 price sets each time. 3. Output data (i.e., multiple observations of price configurations and purchased amounts) are used as inputs to econometric models (using Bayesian methods) to estimate accurate PE values. 4. A disease simulation model will be run with the new PE values as inputs to estimate QALYs gained and health costs saved for the five policy interventions. DISCUSSION: The Price ExaM study has the potential to enhance public health and economic disciplines by introducing internationally novel scientific methods to estimate accurate and precise food PE values. These values will be used to model the potential health and disease impacts of various food pricing policy options. Findings will inform policy on health-related food taxes and subsidies. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12616000122459 (registered 3 February 2016).

Health, Health Inequality, and Cost Impacts of Annual Increases in Tobacco Tax: Multistate Life Table Modeling in New Zealand.

BACKGROUND: Countries are increasingly considering how to reduce or even end tobacco consumption, and raising tobacco taxes is a potential strategy to achieve these goals. We estimated the impacts on health, health inequalities, and health system costs of ongoing tobacco tax increases (10% annually from 2011 to 2031, compared to no tax increases from 2011 ["business as usual," BAU]), in a country (New Zealand) with large ethnic inequalities in smoking-related and noncommunicable disease (NCD) burden. METHODS AND FINDINGS: We modeled 16 tobacco-related diseases in parallel, using rich national data by sex, age, and ethnicity, to estimate undiscounted quality-adjusted life-years (QALYs) gained and net health system costs over the remaining life of the 2011 population (n = 4.4 million). A total of 260,000 (95% uncertainty interval [UI]: 155,000-419,000) QALYs were gained among the 2011 cohort exposed to annual tobacco tax increases, compared to BAU, and cost savings were US$2,550 million (95% UI: US$1,480 to US$4,000). QALY gains and cost savings took 50 y to peak, owing to such factors as the price sensitivity of youth and young adult smokers. The QALY gains per capita were 3.7 times greater for Maori (indigenous population) compared to non-Maori because of higher background smoking prevalence and price sensitivity in Maori. Health inequalities measured by differences in 45+ y-old standardized mortality rates between Maori and non-Maori were projected to be 2.31% (95% UI: 1.49% to 3.41%) less in 2041 with ongoing tax rises, compared to BAU. Percentage reductions in inequalities in 2041 were maximal for 45-64-y-old women (3.01%). As with all such modeling, there were limitations pertaining to the model structure and input parameters. CONCLUSIONS: Ongoing tobacco tax increases deliver sizeable health gains and health sector cost savings and are likely to reduce health inequalities. However, if policy makers are to achieve more rapid reductions in the NCD burden and health inequalities, they will also need to complement tobacco tax increases with additional tobacco control interventions focused on cessation.

Modelling the implications of regular increases in tobacco taxation in the tobacco endgame.

OBJECTIVE: We examine the potential role for taxation in the tobacco endgame in New Zealand, where the goal is to become 'smokefree' (less than 5% smoking prevalence) by 2025. DESIGN: Modelling study using a dynamic population model. SETTING AND PARTICIPANTS: New Zealand, Maori and non-Maori men and women. INTERVENTIONS: Annual increases in tobacco excise tax of 5%, 10%, 15% and 20% (with 10% reflecting the annual increase recently legislated by the New Zealand Government to 2016). RESULTS: With a continued commitment to annual 10% increases in tobacco excise tax, in addition to on-going Quitline and cessation support, New Zealand's smoking prevalence is projected to fall from 15.1% in 2013 to 8.7% (95% uncertainty interval 8.6% to 8.9%) by 2025. This is compared to 9.9% without any further tax rises. With annual tax increases of 20%, the prevalence is projected to fall to 7.6% (7.5% to 7.7%) by 2025. The potential reductions in smoking prevalence are substantial for both Maori and non-Maori populations, although annual tax increases as high as 20% will still only see Maori smoking prevalence in 2025 approaching the non-Maori smoking levels for 2013. Scenario analyses did not suggest that growth of the illicit tobacco market would substantively undermine the impact of tobacco tax rises. Nevertheless, unknown factors such as the gradual denormalisation of smoking and changes to the 'nicotine market' may influence sensitivity to changes in tobacco prices in the future. CONCLUSIONS: Regular increases in tobacco taxation could play an important role in helping to achieve tobacco endgames. However, this modelling in New Zealand suggests that a wider range of tobacco endgame strategies will be needed to achieve a smoke-free goal of less than 5% prevalence for all social groups--a conclusion that could also apply in other countries.

Understanding price elasticities to inform public health research and intervention studies: key issues.

Pricing policies such as taxes and subsidies are important tools in preventing and controlling a range of threats to public health. This is particularly so in tobacco and alcohol control efforts and efforts to change dietary patterns and physical activity levels as a means of addressing increases in noncommunicable diseases. To understand the potential impact of pricing policies, it is critical to understand the nature of price elasticities for consumer products. For example, price elasticities are key parameters in models of any food tax or subsidy that aims to quantify health impacts and cost-effectiveness. We detail relevant terms and discuss key issues surrounding price elasticities to inform public health research and intervention studies.

Predicting high health-cost users among people with cardiovascular disease using machine learning and nationwide linked social administrative datasets.

OBJECTIVES: To optimise planning of public health services, the impact of high-cost users needs to be considered. However, most of the existing statistical models for costs do not include many clinical and social variables from administrative data that are associated with elevated health care resource use, and are increasingly available. This study aimed to use machine learning approaches and big data to predict high-cost users among people with cardiovascular disease (CVD). METHODS: We used nationally representative linked datasets in New Zealand to predict CVD prevalent cases with the most expensive cost belonging to the top quintiles by cost. We compared the performance of four popular machine learning models (L1-regularised logistic regression, classification trees, k-nearest neighbourhood (KNN) and random forest) with the traditional regression models. RESULTS: The machine learning models had far better accuracy in predicting high health-cost users compared with the logistic models. The harmony score F1 (combining sensitivity and positive predictive value) of the machine learning models ranged from 30.6% to 41.2% (compared with 8.6-9.1% for the logistic models). Previous health costs, income, age, chronic health conditions, deprivation, and receiving a social security benefit were among the most important predictors of the CVD high-cost users. CONCLUSIONS: This study provides additional evidence that machine learning can be used as a tool together with big data in health economics for identification of new risk factors and prediction of high-cost users with CVD. As such, machine learning may potentially assist with health services planning and preventive measures to improve population health while potentially saving healthcare costs.

Food pricing strategies, population diets, and non-communicable disease: a systematic review of simulation studies.

BACKGROUND: Food pricing strategies have been proposed to encourage healthy eating habits, which may in turn help stem global increases in non-communicable diseases. This systematic review of simulation studies investigates the estimated association between food pricing strategies and changes in food purchases or intakes (consumption) (objective 1); Health and disease outcomes (objective 2), and whether there are any differences in these outcomes by socio-economic group (objective 3). METHODS AND FINDINGS: Electronic databases, Internet search engines, and bibliographies of included studies were searched for articles published in English between 1 January 1990 and 24 October 2011 for countries in the Organisation for Economic Co-operation and Development. Where ≥ 3 studies examined the same pricing strategy and consumption (purchases or intake) or health outcome, results were pooled, and a mean own-price elasticity (own-PE) estimated (the own-PE represents the change in demand with a 1% change in price of that good). Objective 1: pooled estimates were possible for the following: (1) taxes on carbonated soft drinks: own-PE (n  =  4 studies), -0.93 (range, -0.06, -2.43), and a modelled -0.02% (-0.01%, -0.04%) reduction in energy (calorie) intake for each 1% price increase (n  =  3 studies); (2) taxes on saturated fat: -0.02% (-0.01%, -0.04%) reduction in energy intake from saturated fat per 1% price increase (n  =  5 studies); and (3) subsidies on fruits and vegetables: own-PE (n = 3 studies), -0.35 (-0.21, -0.77). Objectives 2 and 3: variability of food pricing strategies and outcomes prevented pooled analyses, although higher quality studies suggested unintended compensatory purchasing that could result in overall effects being counter to health. Eleven of 14 studies evaluating lower socio-economic groups estimated that food pricing strategies would be associated with pro-health outcomes. Food pricing strategies also have the potential to reduce disparities. CONCLUSIONS: Based on modelling studies, taxes on carbonated drinks and saturated fat and subsidies on fruits and vegetables would be associated with beneficial dietary change, with the potential for improved health. Additional research into possible compensatory purchasing and population health outcomes is needed.

Estimating the cost of new public health legislation.

OBJECTIVE: To develop a new method for estimating the cost to governments of enacting public health legislation. METHODS: We adopted a central government perspective in estimating costs. The parliamentary cost of legislative acts and regulations in New Zealand was calculated from the proportion of parliamentary time devoted to law-making (i.e. sitting days in the debating chamber), and the cost of associated policy advice from government agencies was calculated from the proportion of documented policy issues related to law-making. The relative costs of acts and regulations were estimated from the number of pages in the legislation. FINDINGS: We estimated that, between 1999 and 2010, 26.7% of parliamentary resources and 16.7% of policy advice from government agencies were devoted to generating new laws in New Zealand. The mean cost of an act was 2.6 million United States dollars (US$; 95% uncertainty interval, UI: 1.5 to 4.4 million) and the mean cost of a regulation was US$ 382 000 (95% UI: 22 000 to 665 000). For comparison, the average cost of a bill enacted by the 50 state governments in the United States of America between 2008 and 2009 was US$ 980 000. CONCLUSION: We were able to estimate the cost of new legislation in New Zealand. Our method for estimating this cost seemed to capture the main government costs involved and appears to be generally applicable to other developed countries. Ideally such costs should be included in economic evaluations of public health interventions that involve new legislation.

Health promoting and demoting consumption: What accounts for budget share differentials by ethnicity in New Zealand.

Background: Health demoting consumption of alcohol and tobacco are some of the most important risk factors for health loss worldwide, however there is limited information on these consumption risk factors in New Zealand (NZ) and whether inequities in the risk factors are ethnically patterned. Methods: We used three nationally representative Household Economic Survey waves (2006/07, 2009/10, 2012/13) (n = 9030) in NZ to examine household expenditure for key health risk-related components of consumption by ethnicity, and its contributors to the differences using non-parametric, parametric and decomposition methods. Results: Maori households (NZ indigenous population) were significantly poorer (25% less) than non-Maori households in terms of household per capita expenditure. However, our various econometric estimations suggested that, in relative terms, Maori spent more on tobacco and alcohol, and less on healthcare. The gaps become larger at upper quantiles of the budget share distributions; the composition effect (the gap due to differences in individual and household characteristics between Maori and non-Maori) explains most of the tobacco and alcohol budget share gap between the two groups, and less for healthcare. The structure effect (the gap due to returns to/or effect of individual and household characteristics) contributes very little to the budget share gap for tobacco and drink, but increasingly and predominantly when moving along the distribution of healthcare budget share.The differences between Maori and non-Maori in household ownership, education, and income negatively affect budget share on these health demoting consumption (tobacco and alcohol). The household head's age, education, and employment contributed most to the structure effect. Conclusions: Our study suggested ethnic inequities in the health risk consumption behaviour are evidenced in NZ. Interventions targeting education and employment that significantly affect household budget shares on risk factors (i.e., harmful consumption) for health loss may help narrow the gaps.