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Objective: To estimate coronary heart disease (CHD) incidence, prevalence, survival, case fatality and mortality for Maori, in order to support service planning and resource allocation. Methods: Incidence was defined as first occurrence of a major coronary event, i.e. the sum of first CHD hospital admissions and out-of-hospital CHD deaths in people without a hospital admission for CHD in the preceding five years. Data for the years 2000-02 were sourced from the New Zealand Health Information Service and record linkage was carried out using a unique national identifier, the national health index. Results: Compared to the non-Maori population, Maori had both elevated CHD incidence and higher case fatality. Median age at onset of CHD was younger for Maori, reflecting both higher age specific risks and younger population age structure. The lifetable risk of CHD for Maori was estimated at 37% (males) and 34% (females), only moderately higher than the corresponding estimates for the non-Maori population, despite higher Maori CHD incidence. This reflects the offsetting effect of the higher 'other cause' mortality experienced by Maori. Median duration of survival with CHD was similar to that of the non-Maori population for Maori males but longer for Maori females, which is most likely related to the earlier age of onset. Conclusions: This study has generated consistent estimates of CHD incidence, prevalence, survival, case fatality and mortality for Maori in 2000-02. The inequality identified in CHD incidence calls for a renewed effort in primary prevention. The inequality in CHD case fatality calls for improvement in access for Maori to secondary care services. Key words: coronary disease, epidemiology, lifetable, New Zealand, ethnicity. doi: 10.1111/j.1753-6405.2009.00412.x

Objective: To estimate the contribution of health care to health gain, and to ethnic and socio-economic health inequalities, in New Zealand over the past quarter century. Method: Amenable and all-cause mortality rates by ethnicity and equivalised household income tertile from 1981-84 to 2001-04 were estimated from linked census-mortality datasets (the New Zealand Census-Mortality Study). Amenable mortality (deaths under age 75 from conditions responsive to health care) was defined using a classification recently developed for use in Australia and New Zealand. The contribution of health care to the observed improvement in population health status was estimated by the ratio of the difference in amenable to the difference in all-cause mortality over the observation period. Results: Trends in amenable causes of death were estimated to account for approximately one-third of the fall in mortality over the past quarter century, for the population as a whole and for all income and ethnic groups except Pacific peoples, for whom there was no reduction in amenable mortality. In 2001-04, amenable causes accounted for approximately one quarter of the mortality gap between all ethnic groups compared to the European/Other reference. Discussion: Our finding provides one indicator of the social impact of health care over this period. More importantly, that Pacific peoples seem to have benefited less than other ethnic groups calls for urgent explanation. Also, our finding that amenable causes account for about one quarter of current mortality disparities, clearly indicates that improvement in access to and quality of health care for disadvantaged groups could substantively reduce health inequalities. Key words: amenable mortality, trends, New Zealand

Objective: To estimate the contribution of trends in three risk factors--systolic blood pressure (SBP), total blood cholesterol (TBC) and cigarette smoking--to the decline in premature coronary heart disease (CHD) mortality in New Zealand from 1980-2004. Method: Risk factor prevalence data by 10-year age group (35-64 years) and sex was sourced from six national or Auckland regional health surveys and three population censuses (the latter only for smoking). The data were smoothed using two-point moving averages, then further smoothed by fitting quadratic regression equations (SBP and TBC) or splines (smoking). Risk factor/CHD mortality hazard ratios estimated by expert working groups for the World Health Organization Global Burden of Disease Study 2001 were used to translate average annual changes in risk factor prevalences to the corresponding percentage changes in premature CHD mortality. The expected trends in CHD mortality were then compared with the observed trend to estimate the contribution of each risk factor to the decline. Findings: Approximately 80% (73% for males, 87% for females) of the decline in premature CHD mortality from 1980 to 2004 is estimated to have resulted from the joint trends in population SBP and TBC distributions and smoking prevalence. Overall, approximately 42%, 36% and 22% of the joint risk factor effect was contributed by trends in SBP, TBC and smoking respectively. Conclusion: Our estimate for the joint risk factor contribution to the CHD mortality decline of 80% exceeds those of two earlier New Zealand studies, but agrees closely with a similar Australian study. This provides an indicator of the scope that still remains for further reduction in CHD mortality through primary and secondary prevention. Key words: Risk factor, coronary heart disease, New Zealand doi: 10.1111/j.1753-6405.2008.00186.x

Objective: To produce internally consistent estimates of coronary heart disease (CHD) incidence, prevalence, survival and mortality as a decision aid for service planning and resource allocation. Methods: Incidence was defined as first occurrence of a major coronary event, i.e. the sum of first CHD hospital admissions and out-of-hospital CHD deaths without a hospital admission for CHD in the preceding five years. Mortality was defined as the sum of deaths coded to CHD and deaths coded to related causes but with prior hospitalisation for CHD (in the preceding five years). Data were sourced from the New Zealand Health Information Service and record linkage was carried out using a unique national identifier, the National Health Index (NHI). Given estimates for incidence and mortality, multi-state lifetables were built and estimates for prevalence, survival, lifetable risk, and median age at onset extracted. Results: Estimated prevalence of CHD increased exponentially from around 2% for males and 0.5% for females at age 40-44 to peak at around 18% and 12% respectively at age 85-89. Median age at onset of CHD was 67.5 years for males and 77.5 years for females. Median survival duration was 9.5 years for males and 6.2 years for females. The lifetable risk of CHD was estimated at 35% for males and 28% for females. Conclusions: This study provides a complete and internally consistent picture of the descriptive epidemiology of CHD for the whole New Zealand population in 2001-03. This information will be useful for planning and funding of coronary prevention, treatment and rehabilitation services. Keywords: Coronary heart disease; incidence; prevalence; mortality; surveillance.

Objective: To quantify the contribution of health care to ethnic and socio-economic inequalities in health in New Zealand in 2000-02, using the concept of 'amenable' mortality (deaths at ages 0-74 years from causes responsive to health care). Data sources and Methods: Mortality data for 2000-02 were provided by the New Zealand Health Information Service and 2001 Census population data were provided by Statistics New Zealand. The classification of ICD-10 codes as amenable or non-amenable used in the Australian and New Zealand Atlas of Avoidable Mortality (2006) was adopted. Ethnicity was categorised as Maori, Pacific or European/Other. Socio-economic position was measured using a Census-based small area deprivation index, the NZDep2001. Mortality rates were standardised for age by the direct method for the ethnic group comparisons, and for both age and ethnicity for the deprivation group comparisons. The contribution of health care to health inequality was then quantified as the ratio of the difference in standardised amenable mortality rates to the difference in standardised total mortality rates (in the age group 0-74 years) between relevant groups. Results: Amenable causes of death were estimated to account for 27%, 34%, 33% and 44% of the total mortality disparity (0-74 years) for Maori males, Maori females, Pacific males and Pacific females respectively, relative to their European/Other counterparts (adjusting for age). The corresponding proportions for the 'deprived' population relative to the 'non-deprived' population were 26% (males) and 30% (females), adjusting for age and ethnicity. Conclusions: Amenable causes of death made a substantial contribution to differences in mortality in the 0-74 year age range between ethnic and socio-economic groups in New Zealand in 2000-02, ranging from 26-44% depending on the group. Key words: health, inequality, amenable morality, New Zealand

Objective: To describe the co-occurrence and clustering of healthy and unhealthy behaviours in New Zealand. Method: Data were sourced from the 2002/03 New Zealand Health Survey. Behaviours selected for analysis were tobacco use, quantity and pattern of alcohol consumption, level of physical activity, and intake of fruit and vegetables. Clustering was defined as co-prevalence of behaviours greater than that expected based on the laws of probability. Co-occurrence was examined using multiple logistic regression modelling, while clustering was examined in a stratified analysis using age and (where appropriate) ethnic standardisation for confounding control. Results: Approximately 29% of adults enjoyed a healthy lifestyle characterised by non-use of tobacco, non- or safe use of alcohol, sufficient physical activity and adequate fruit and vegetable intake. This is only slightly greater than the prevalence expected if all four behaviours were independently distributed through the population i.e. little clustering of healthy behaviours was found. By contrast, 1.5% of adults exhibited all four unhealthy behaviours and 13% exhibited any combination of three of the four unhealthy behaviours. Unhealthy behaviours were more clustered than healthy behaviours, yet Maori exhibited less clustering of unhealthy behaviours than other ethnic groups and no deprivation gradient was seen in clustering. Discussion: The relative lack of clustering of healthy behaviours supports single issue universal health promotion strategies at the population level. Our results also support targeted interventions at the clinical level for the 15% with 'unhealthy lifestyles'. Our finding of only limited clustering of unhealthy behaviours among Maori and no deprivation gradient suggests that clustering does not contribute to the greater burden of disease experienced by these groups. Key words: Behaviour, clustering, lifestyle, health promotion.

Objective: To describe the co-occurrence and clustering/aversion of tobacco use and obesity in New Zealand. Method: Data were sourced from the 2002/03 New Zealand Health Survey, a nationally representative household survey that included measured body mass index (BMI) and self-reported smoking status. The association of cigarette smoking, obesity, and the combination of these risk factors with socio-demographic variables was analysed by multiple logistic regression. Clustering/aversion (defined as observed prevalence of [smoking + obesity] > or < expected prevalence, where expected prevalence = prevalence of [smoking] x prevalence of [obesity]) was also estimated. Results: The joint prevalence of smoking plus obesity in the adult population (15+ years) was 4.5%. However, this was 10% for Maori and 8.5% for deprivation quintile 5. Adjusting for relevant covariates, Maori were twice as likely to have both risk factors as non-Maori. A smooth deprivation gradient was found, with deprivation quintile 1 (least deprived) only one-fifth as likely to have both risk factors as quintile 5 (most deprived). There was no evidence of clustering, and aversion (negative clustering) was demonstrated only for middle-aged adults and for Maori. Discussion: Since smoking cessation is associated with weight gain, substantial aversion might have been expected across all subgroups, yet this was not found. The most likely explanations are that the extent of weight gain associated with smoking cessation has been overestimated or is often not sustained. Even so, health promotion and clinical interventions need to take the dually exposed population into account, addressing not only the unhealthy behaviours themselves but also the social context in which dual exposure occurs.

Objectives: First, to establish whether a deprivation gradient in all-cause mortality exists for all ethnic groups within New Zealand; second, if such gradients do exist, whether their absolute slopes are the same; and third, if such gradients exist, what impact the unequal deprivation distributions of the different ethnic groups have on the observed ethnic inequalities in life expectancy at birth. Method: Abridged lifetables for the period 1999-2003 were constructed using standard demographic methods for each of four ethnic groups (Asian, Pacific, Maori and European) by NZDep2001 quintile and sex. Gradients were estimated by fitting generalised linear models to the quintile-specific life expectancy estimates for each ethnic group (by sex). The contribution of variation in deprivation distributions to inter-ethnic inequalities in life expectancy was estimated by re-weighting the quintile-specific mortality rates for each ethnic group using weights derived from the European deprivation distribution and recalculating the lifetable. Results: All four ethnic groups exhibit deprivation gradients in all-cause mortality (life expectancy). Maori show the steepest gradients, with slopes approximately 25% steeper than those of Europeans for both males and females. By contrast, gradients among Asian and Pacific peoples are shallower than those of their European counterparts. Conclusion: While socio-economic gradients in health exist among all ethnic groups, they are relatively shallow among Pacific and (especially) Asian peoples. For these ethnic groups, caution should be exercised in applying deprivation or other socio-economic measures as proxy indicators of need for health services.

Introduction and Aims: Alcohol is an increasingly important risk factor in the global burden of disease. The acute harms experienced and persistence of drinking patterns established in adolescence motivate investigating influences on youth drinking. The aim is to examine association between heavier drinking in young people and their choice of beverage type, purchase outlet and price.Design and Methods: A nationally representative sample of New Zealand drinkers (N = 1056) aged 16-19 years recruited using random digit dialling was surveyed in 2012 as part of the International Alcohol Control study. Typical quantities consumed and frequency of alcohol consumption categorised respondents into lower, medium and heavier consumption groups. Beverage choice, prices paid and on or off-premise purchase were related to consumption using univariate analysis. Logistic analysis was used to examine multivariate factors predicting membership of consumption groups.Results: Twenty percent of the sample consumed six or more drinks at least once a week, increasing to 1 in 4 for those 18 years and older. Heavier drinkers consumed more alcohol in the form of ready to drinks (RTD) especially high-potency RTDs. Lower consumers drank greater proportion of wine. Heavier drinkers paid less than medium consumers who paid less than lower consumers. High-potency RTDs were cheaper per unit of alcohol than other beverages and chosen by heavier drinkers resulting in lower prices.Discussion and Conclusions: Heavy consumption of alcohol remains common in New Zealand young drinkers. Heavier drinkers paid less to purchase alcohol and consumed more alcohol in the form of high-potency RTDs. [Wall M, Casswell S, Yeh L-C. Purchases by heavier drinking young people concentrated in lower priced beverages: Implications for policy. Drug Alcohol Rev 2017;36:352-358]. [ABSTRACT FROM AUTHOR]

This paper presents a field-programmable gate array (FPGA)-based control integrated circuit (IC) for controlling the pulsewidth modulation (PWM) inverters used in power-conditioning systems for ac-voltage regulation. We also propose a multiple-loop control scheme for this PWM inverter control IC to achieve sinusoidal voltage regulation under large load variations. The control scheme is simple in architecture and thus facilitates realization of the proposed digital controller for the PWM inverter using the FPGA-based circuit design approach. Bit-length effect of the digital PWM inverter controller has also been examined in this paper. The designed PWM inverter control IC has been realized using a single FPGA XC4005 from Xilinx, Inc., which can be used as a coprocessor with a general-purpose microprocessor in application of ac-voltage regulation. Owing to the high-speed nature of FPGA, the sampling frequency of the constructed IC can be raised up to the range that cannot be reached using a conventional digital controller based merely on microcontrollers or a digital signal processor (DSP). Experimental results show the designed PWM inverter control IC using the proposed control scheme can achieve good voltage regulation against large load variations. Index Terms - Digital control, FPGA, PWM inverter, UPS.

Aims: Roll-your-own (RYO) tobacco use is exceptionally high in New Zealand with 61% of current smokers using it exclusively or in conjunction with tailor-made (TM) cigarettes. This study examines the characteristics of RYO users and their likelihood of quitting smoking compared to TM and mixed tobacco users., Methods: A random sample of Quitline callers with a booster sample of Māori, was invited to participate in a telephone survey three times within a 12-month period. The response rates for the first survey were 57% for Māori and 63% for non-Māori, resulting in a total of 2002 participants. Among these participants, 64% completed the 6-month follow-up and 42% completed the entire study. Two participants were excluded from this analysis as they smoked neither RYO nor TM. We compared the eligible participants' characteristics and quitting outcomes by tobacco type. Quit status was assessed by 7-day abstinence at 6- and 12-month and we used a conservative approach to treat missing cases., Results: RYO use was common among particular smokers such as Māori, male, and low socioeconomic status subjects. When sociodemographic and smoking variables were controlled for using a logistic regression model, quit rates were not different by tobacco type., Discussion: This study confirms the different characteristics of RYO, TM and mixed tobacco users, and fills a gap of limited research about quitting success of RYO smokers.

Aim: To describe the method developed by the National Cervical Screening Programme (NCSP) for review of cases of cervical cancer; present results from the first 4 years of the review and compare these results with those of the earlier New Zealand Cervical Cancer Audit., Methods: Linkage of cervical cancer registrations from the New Zealand Cancer Registry to smear histories from the NCSP Register via the National Health Index, for the 4-year period 2003-06., Results: A total of 625 women were registered with cervical cancer from 2003-06, of whom 438 were eligible for linkage (women diagnosed with squamous or adenosquamous cervical cancer at <80 years of age). Of these 438 eligible cases, 348 were histologically invasive and 90 were microinvasive. Unlike histological stage, clinical FIGO stage was missing in approximately 50%. Linkage to screening history revealed that 202 of the 438 eligible women (46%) had never been enrolled in the NCSP; 137 (31%) were enrolled but had only been infrequently or irregularly screened; and 85 (20%) developed cancer despite regular screening (data were missing for 3 women). These results were similar to those found in the New Zealand Cervical Cancer Audit, covering the period 2000-2002., Conclusions: Ongoing linkage of cancer data to screening data can be used to monitor the performance of the NCSP. Our finding that 80% of potentially preventable cervical cancers involve women who are not enrolled in the Programme or who have been only infrequently and irregularly screened, confirms that improving Programme coverage (currently around 72%) remains a priority. Further investigation (phase 2) is required for the small number of women who develop cervical cancer despite regular screening (average of 21 per year, or approximately 20% of eligible cases), to distinguish interval cancers from possible Programme quality issues.