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Regulating Public Health in New Zealand

Wednesday, September 1st, 1999
Alistair Woodward, Professor of Public Health - Dr Tony Blakely, Registrar Public Health - Philippa Gander, Associate Professor - Philippa Howden-Chapman, Senior Lecturer - Department of Public Health, Wellington School of Medicine, University of Otago, New Zealand




Overview

This paper continues a series on the current state of public health in New Zealand. Previous papers have included the views of providers of public health services and an analysis of the policy framework for public health.

We begin with the question "How well is New Zealand doing in public health?" This leads to a discussion of what we know about the fundamental underlying causes of disease and injury, and the implications for public health actions (which include regulation). We point out that regulation outside the health sector can have profound effects on the health of the population and, as an example, describe recent changes in regulations controlling hours of work. These changes are unprecedented internationally and, potentially, have important consequences for occupational health. We then turn to the use of regulation as a means of promoting public health. New Zealand has undertaken a radical review of its public health legislation and the current intention is to move to a risk-based approach to regulation. If this change is implemented, it will be far-reaching. We explain what is meant by a risk-based approach and what the strengths and weaknesses of such legislation might be. One consideration is the limits of regulation: in many instances regulation on its own will not be sufficient to reduce the burden of disease and ill health. As an example, we describe recent efforts to control illness due to infection with the hepatitis B virus.

The key points in the paper are:

  • The underlying causes of disease and illness are social and economic.
  • New Zealand is undergoing radical changes in the social and economic environment and these changes are likely to have far-reaching effects on health.
  • Interventions that are confined to the health sector will have limited effect in improving the health of the population.
  • Regulation for public health requires a broad definition of what constitutes "risks" to health.



Public Health – How Well is New Zealand Doing?

There are many ways of measuring public health. In the previous issue of Healthcare Review – Online in this series, Gillian Durham summarised a number of New Zealand health indicators.  1   She concluded that the picture was a mixed one: in some areas New Zealand is doing well, both by international standards and by comparison with historical results, while in other respects current trends are not favourable.

Life expectancy in New Zealand has risen throughout this century, with the exception of a plateau during the 1960s at the height of the cardiovascular disease epidemic, when there was little change for either men or women. However, the rate of improvement in New Zealand has not matched that of other countries, and in many instances New Zealand has been overtaken. For example, in 1961 male life expectancy at birth in New Zealand was almost half a year greater than in Australia (68.4 years compared with 68.0); in 1996 New Zealand men were more than a year behind (74.3 compared with 75.4).  2  ,   3  

The overall reduction in mortality has not been shared by all groups in the New Zealand population. Life expectancy amongst Maori has been considerably less than for non-Maori since reliable national statistics were first collected for both groups in the 1950s.   4   In 1956 the difference was 11.7 years for men and 15.2 years for women. The gap narrowed by 1986 (to 3.9 years for men and 5.1 years for women), but since 1990 there has been no further improvement for Maori although non-Maori life expectancy has continued to rise.   3   In 1997 there appeared to be, for the first time, a decline in life expectancy for Maori but the data are not strictly comparable with earlier years due to changes in the coding of ethnicity.

The relatively high rates in New Zealand of mortality in middle age (where the bulk of Maori deaths occur) are apparent in other statistics, such as potential years of life lost under age 70. In comparison with other members of the OECD, New Zealand has high levels of premature mortality, and trends in the last five years for which there are comparable data (1990–1995) show a much slower rate of improvement than any other countries, with the exception of Eastern European states. (Table 1)

What conclusions can be drawn from these statistics, bearing in mind that they provide only a partial account of changes in the health of the New Zealand population? In the simplest terms, it appears that New Zealand is doing better than it has in the past, but not as well as most other countries with which we tend to compare ourselves. Moreover, health inequalities within New Zealand are increasing and the health of Maori (as measured by mortality statistics) is not progressing.

Table 1. Premature mortality in selected OECD countries, 1995, and trends 1960–1995. Potential years of life lost under age 70, per 100,000 population.
Females Males
Annual rate of decline (%) Level
1995		 Annual rate of decline (%) Level
1995
1960-80 1980-90 1990-95 1960-80 1980-90 1990-95
Australia -2.3 -2.6 -3.0 3103 -1.6 -3.2 -3.5 5193
Germany -3.5 -2.3 -1.7 3337 -2.7 -1.9 -1.0 6505
Ireland -2.6 -2.7 -3.6 3444 -1.5 -2.9 -2.7 5795
Netherlands -2.0 -1.2 -1.4 3262 -1.2 -1.9 -2.2 5139
NZ -1.1 -2.7 0.4 4775 -1.1 -2.2 -0.2 7342
UK -1.5 -2.6 -2.3 3616 -1.5 -2.6 -2.6 5690
US -2.1 -1.7 -1.0 4591 -1.6 -1.6 -0.9 8401
 
Average OECD -2.6 -2.3 -2.8 -1.7 -2.2 -2.6
Reference: OECD Health Data 1998

What causes good public health? This appears to be a straightforward question but there is no simple answer. In the past the most powerful influences on health were factors in the social and physical environment such as quality of drinking water, amount and variety of food, adequate housing and safe work. While the formal health care system has played a stronger role in the second half of the 20th century than the first half, environmental factors outside the health sector still have a pervasive influence on the health of groups and individuals. Social characteristics such as income and education influence both the incidence of disease and the utilisation of health services for the treatment of disease. For example, a study of the North Health region between 1982 and 1994 found that mortality rates were almost twice as high in the lowest socio-economic groups compared with the most advantaged, and this ratio altered little when considering only mortality due to conditions amenable to medical interventions.  5   Despite all the advances that have been made in medicine, the overall impact of social position on health status is still much stronger than the effects of health care interventions. For example, New Zealand cancer deaths due to smoking would be reduced by about 70% if the rate in the most socially advantaged group applied across the whole population.   6  

In the last 15 years New Zealand has experienced massive social change and this has impinged on all the basic determinants of good public health. For example, working conditions for many New Zealanders have altered greatly, partly in response to international pressures and partly as a result of local factors such as the Employment Contracts Act 1991. New Zealanders have seen reduced security of employment, increased casualisation of labour and more frequent shift work. Economic and policy reforms have led to benefit cuts, a decline in long-term secure employment and rising accommodation costs. These have affected particularly severely vulnerable groups in the community such as single parent families, families with small children, Maori and Pacific Islanders. There has been over the same period, as a result of the reforms, a marked widening in income inequalities. Between 1981 and 1996, average household disposable incomes were static, or fell, for low and middle-income New Zealanders, but the most affluent households (the top 10%) increased their incomes by almost a third on average.   7  

It is difficult to identify precisely how these social changes have impacted on health. However, recent work by Charles Waldegrave and his colleagues has provided insights into likely connections between social disadvantage and health outcomes.   8   They interviewed 401 people from a random sample of households with dependent children and a combined income of under $25,000 (roughly 20% of New Zealand households with children are in this income band). Half the participants reported that they had been unable to provide meals for the household in the previous three months, due to lack of money. Forty percent of households were over-crowded, according to criteria developed by the Ministry of Housing (and 25% were paying half or more of their income on rent or mortgage). More than half the households had members who had not visited a doctor in the previous year, when they thought they needed to, because they could not afford it. Almost 60% had missed seeing a dentist for the same reason.

Many of these factors – income, housing, employment – are amenable to policy and regulation. We have chosen two examples for closer inspection. Both are novel approaches to regulation and have attracted interest internationally. The first, changes in rules for hours of work, is an instance of regulation outside the health sector that has the potential to increase illness and injury. The second example is the development of new risk-based public health legislation.



Hours of Work

With the introduction of the Employment Contracts Act 1991, New Zealand embarked on a radical experiment in deregulation that many other countries are still debating.   9  However, there has been minimal systematic monitoring of the effects of this legislation on work practices or on possible health and safety outcomes. Since the introduction of the Employment Contracts Act, there have been a number of key changes in the labour market (Table 2). In addition to overall growth in the number of people employed, there have been increases in the number of hours that they are working and in the number of people working multiple jobs. At the same time, union membership has declined markedly.

Table 2: Changes in the Labour Market

  1991 1996 * change
Number of people employed
all industries		 1,479,200 1,648,200 + 11.4%
Average paid weekly hours
all industries		 38.66 39.39 + 0.73 h
Multiple job holders
Men
Women		 64,900
31,500
33,300		 76,600
36,600
40,100		 + 18.0%
+ 16.2%
+ 20.4%
Number of union members
(Dec 1991 - * Dec 1995)		 603,118 362,200 - 39.9%
% of employed people in unions
(Dec 1991 - * Dec 1995)		 40.8% 22.9% - 17.9%
All data from Labour Market 1996 Tables, Statistics New Zealand   10  

These changes run counter to current trends in Europe and Scandinavia, where there is a growing movement to reduce individual working hours and increase the number of people active in the workforce. Recent examples include: reductions from 8-hour to 6-hour working days among public sector employees in Finland   11   and caregivers in Sweden   12  ; reductions to 35.0 hours or 33.5 hours per week, with increased annual leave, in German manufacturing industries   13  ; collective reduction of weekly working hours from 38 to 36 in parts of Holland   14  ; and a variety of different models for reducing individual working hours that have been implemented in the public sector in Switzerland   15  . The European Union’s working time directive limits the maximum working week to 48 hours   16  . A recent survey of anaesthetists practising in New Zealand found that the average working week of both trainees and specialists exceeded 48 hours, and that 32% recalled making fatigue-related errors in clinical practice in the preceding 6 months.  17  

There is a particularly marked lack of monitoring of shift work prevalence and practices in New Zealand, with no national data sources evaluating the times at which people are working (as opposed to the number of hours being worked). This is concerning, because working at unusual hours (especially working at night) imposes significant physiological and lifestyle challenges and can have detrimental effects on worker health, safety and productivity   18 - 24  . A nation-wide review of collective employment contracts  9   found that shift work provisions appeared in contracts covering 57% of the employee sample (416,000 employees). This represents 25% of the total workforce, based on 1996 figures   10  , and is a conservative estimate since it includes only the collective contracts that were provided voluntarily for the study. Another trend since the implementation of the Employment Contracts Act has been the removal of "clock hours" provisions from collective employment contracts, with 49% of the employees sampled in 1996/97 not being covered. "Clock hours" define "normal" hours of work, outside of which an employer is required to pay premium rates. Without clock hours provisions, the contractual definition of shift work becomes unclear.  [ A ]  

The climate of deregulation is also influencing the transportation sector, where hours-of-work regulations have been the traditional means of addressing the safety risks associated with workplace fatigue. Thus, for example, the Land Transport Safety Authority has been assessing the feasibility for the New Zealand trucking industry of moving to a "fatigue management" approach, as an alternative to prescriptive hours-of-work regulations. Queensland is currently trialing such an approach, which in essence requires employers to demonstrate that they have comprehensive policies and procedures in place to manage workplace fatigue. They may then operate outside the prescriptive hours-of-work regulations, in specified circumstances. A company’s policies and procedures are subject to an initial accreditation process, and are then audited periodically by the regulator.  [ B ]   A similar approach is being considered by the New Zealand Civil Aviation Authority for air traffic controllers. Fatigue management programmes aim to comprehensively address the underlying causes of workplace fatigue. However, they remain largely untested in terms of their effects on safety or the increased flexibility that they are said to offer employers. There are concerns that fatigue management approaches may significantly increase the complexity of compliance and policing. Penalties for non-compliance are also an issue. In Queensland, repeated failure of regulatory audits leads to a company being required to return to the prescriptive hours-of-work regime. On the other hand, in Western Australia, there are no hours-of-work limitations for truck drivers, and the aim is to enforce fatigue management under the duty-of-care requirements in the state’s occupational health and safety legislation.

New Zealand’s Health and Safety in Employment Act 1992 came into effect on 1 April 1993. The Act is administered by the Occupational Safety and Health Service (OSH) of the Department of Labour. Up until 30 May 1997, the OSH fatalities database included 190 workplace deaths, 35 of which had resulted in prosecution of employers (source: question to Parliament no. 9967). The database does not include road, sea, or air accidents, which are held by other agencies. Nor does it include deaths from occupationally related diseases. OSH has a dual role in educating employers about compliance with the Act, and in policing the Act, and its procedures, effectiveness, and level of resourcing are issues of concern.   27  



Towards a New Public Health Act – The Risk Framework

What role is there for regulation as an instrument of public health intervention? The New Zealand Ministry of Health has recently undertaken a major review of its public health legislation, and its current proposal is to move to a risk-based approach to regulation. In the past legislation has dealt mainly with the control of communicable diseases and environmental risks. However, the Ministry discussion document proposes a broader goal for the new Act: "to improve, promote and protect the public health".   28  Such a change would be far-reaching.

In the new legislation, the Ministry is seeking a transparent approach that would assist decision-makers to be consistent in managing the increasing number of complex issues that can potentially affect public health. For example, the Ministry has recently had to respond to a range of new public health issues, including genetically modified food, exotic mosquitoes with potential to carry human disease and outbreaks of illness due to VTEC (Very Toxigenic E. coli).

Risk management is more than risk analysis and needs to look strategically at the specific cultural context of the country managing the risk, the organisational arrangements of the responsible agencies and the public consultations necessary. There is no universal level of acceptable risk, as risk acceptance is largely determined by individual and community values. It has been noted that the person talking about acceptable risk is almost certainly not the person or group creating that risk in the first place. Indeed, Clarke   29   argues that risk assessments are claims to legitimacy that are directed in large part at other organisations and that the role of organisations is crucial, as organisations, not disparate members of the general population, are the final arbiters of risk.

The risk-based approach being considered by the Ministry will involve the systematic monitoring of potential health hazards and, importantly, determination of which hazards involve health risks of national significance after consultation with the public and expert groups. A public-health-risk management decision-making approach is being developed that will help to determine when legislative or alternative control measures are needed and when to alert or monitor other agencies of government which may have responsibilities for managing a particular risk. An effective management system has to consider emerging public health risks at local, national and international levels and must be compatible with other risk management frameworks such as that of the Environmental Risk Management Authority, and the generic Standards Association framework – the revised Australian/New Zealand Standard (AS/NZS 4360:1999). (The latter does not explicitly refer to human health and ecosystems.)

The first stage of the proposed risk management system is an explicit comparative risk assessment in order to systematically identify and rank evident public health risks and to identify public health emergencies that require urgent responses. One strength of this approach is that the identification of hazards and risks will require a greater investment in surveillance and information systems than at present so that one outcome will be, hopefully, improved awareness of emerging risks.

Once the scope of risks and their distributional impacts are identified, the process seeks focussed, systematic and cost-effective public participation. This would be done through working groups, which include those with technical expertise and stakeholders, especially individuals and representatives of groups who are affected by the risks under consideration. Such working groups allow communication "in" as well as "out", and are part of the essential process needed to build a negotiated consensus around an operational definition of tolerable risk, and to create a climate of trust in the process. This is critical to risk management.

While it is important to involve key stakeholders in the risk-management process, it is not necessary for all decisions to be acceptable to all stakeholders. Conflicts over values and pervasive distrust in risk management cannot easily be reduced by technical analysis as risk assessment is inherently subjective and represents a blending of science and judgement, with important psychological, social, cultural and political factors.   30  

The second stage of a desirable process is identifying those organisations (eg, promoters of risky new technologies) that clearly contribute to risk and uncertainty about impacts on the community’s health. At least part of the contribution of such organisations to risk and uncertainty is an external cost which should be borne by these organisations. To ensure this happens would require careful estimation and charging of costs where risk and uncertainty have been created, an understanding by the public of the reasons for this approach, and acceptance of the need for enforcement. People can now see the logic of tobacco companies, for example, paying a price for cancer deaths; a similar logic applies in charging the purveyors of new, risky products a price (perhaps in the form of a bond) "up front". Such a price would have the advantage of averting risk and creating incentives to innovate to prevent damage.   31  

In the third stage of the process (having identified and compared the public health risks, built a climate of trust by involving stakeholders and having identified risk costs and who should bear them) a range of policy options is developed. Possible interventions could include regulation, but may be also:

  • do nothing/monitor only, or conduct further research, eg, for major social policy changes such as housing policy changes
  • provide information, eg, for emerging communicable diseases
  • resource educational programmes through central or local government
  • develop guidelines, eg, for operators of public swimming pools
  • develop a code of practice, eg, for body tattooing
  • develop regulatory standards, eg, for tobacco advertising
  • use economic tools, eg, an increase in excise tax for tobacco.

A strength of this approach is that it should be transparent to public scrutiny. A major concern is that the monitoring and identification of a range of health hazards is more likely to include environmental factors (such as structures, activities, animals, organisms, substances or products), than social and economic factors (such as income distribution, housing or industrial processes and occupational working conditions). Yet, broader social and economic factors, as previously pointed out, are likely to have the largest impact on the public health.

Also, given the importance of socio-economic factors, the most effective approach for promoting health may not be through regulation. Regulation has an important place as a "bottom line" but too great a reliance on regulation risks narrowing the approach to public health action, since regulation is only one lever for change. Regulation has its limits and in many instances regulation on its own will not be sufficient to reduce the burden of disease and ill health.

More broadly, seeing public health in terms of separate risks that should be individually addressed – rather than connected opportunities where health gains can be made – has the disadvantage of narrowing the focus away from the broader issues of population health. Rather than focussing on, for example, one communicable disease at a time, it may be preferable to address the wider set of socio-economic causes (such as overcrowded housing and inadequate income for food security) behind these diseases.

An example of a major public health risk seen in relative isolation in the New Zealand context, is the hepatitis B virus. We describe recent efforts to control illness due to infection below.



Limits to Regulation – The Case of Hepatitis B

Other than immunisation and particular occupational exposures, public health policy on hepatitis B is not subject to specific regulation. But hepatitis B has been, and continues to be, a public health problem in New Zealand. We can learn much from the hepatitis B story in New Zealand about policy-making institutions, the interface of limited research evidence and the need to make rapid decisions about public health programmes and the power and influence of persistent lobbying by concerned community groups.

In the acute phases, hepatitis B can cause anything from mild to life-threatening illness. Fortunately, the incidence of acute hepatitis B has plummeted in New Zealand following the introduction of immunisation against hepatitis B on the national childhood immunisation schedule in the 1980s.  32   The timing of the institution of hepatitis B immunisation on the schedule should be largely credited to Mr Sandor Milne, originally a laboratory staff member of Whakatane Hospital and now Director of the Hepatitis Foundation. By constant lobbying of the then Department of Health, Mr Milne probably brought forward the implementation of hepatitis B immunisation on the national schedule by many years. Whilst supported by regulation, a timely response to the acute hepatitis B problem in New Zealand was largely brought about by lobbying from outside government institutions.

Since the 1980s, attention has appropriately shifted from the problem of acute hepatitis B to the pool of 30–40,000 carriers of hepatitis B in New Zealand. Carriers are people who have been infected in the past by hepatitis B, and are unable to clear the virus. Carriers may inadvertently then pass the hepatitis B virus on to other people. Of greatest concern are the health risks faced by carriers; they have a 20% lifetime risk of developing cirrhosis,   33   and Maori male carriers have a 10–15% risk of developing primary liver cancer by age 70.   34   Screening of specific populations at higher than average risk of being a hepatitis carrier (eg, Maori, Pacific Island and Asian people, in northern and eastern parts of the North Island) to, first, detect carriers and, secondly, to treat and monitor identified carriers, is a possible public health response. However, screening is of uncertain effectiveness, there being an absence of randomised controlled trials (RCT) of screening, and a myriad of important assumptions that affect the final cost-effectiveness.   35   A working party convened in 1994 recommended against population-based screening.   33   Following review of the 1994 report by two international experts, a further working party in 1996 suggested that if the value of a life year is greater than $31,000, screening was cost-effective. This working party recommended a pilot programme. Just as the Health Funding Authority (HFA) was about to implement that pilot programme, Cabinet abandoned it on 3 July 1998, stating that instead a national programme would be conducted for only twice the cost ($22.5 million) of the pilot. Subsequent planning by the HFA, however, demonstrated that it was not possible to conduct a national programme for the allocated money. The discussion then changed to a national programme with a staged roll-out, ie, back to a pilot programme, but with the start date delayed by approximately a year from the previously proposed start date.

Several lessons arise from the hepatitis B story in New Zealand. First, policy resulting from lobbying is a two-edged sword: without doubt the lobbying by the Hepatitis Foundation in the 1980s for immunisation saved many lives, but the recent lobbying and governmental response may have served only to delay the implementation of what is essentially still a pilot screening programme. Secondly, requiring RCT evidence before the implementation of any screening programme, in retrospect, is probably too rigorous. The hepatitis B carrier problem is with us now, and no RCT will produce results for many years. This is too long to wait given that the hepatitis B carrier problem is a problem for New Zealand adults now – not in the future. Policy analysis should make greater use of modelling to anticipate the likely cost-effectiveness of programmes. Thirdly, evaluation of a pilot programme must be protected. Information from evaluation is essential for updating models of the likely cost-effectiveness of screening programmes and for making the critical decision whether to stop or roll-out the programme nationally. New Zealand is also in a unique position of being able to provide data to the international community – even if not data from a RCT. Finally hepatitis B is a reminder that regulation is not the only means to address substantial public health problems.



Footnotes

  • A. Nevertheless, from a physiological point of view, shiftwork includes any work pattern that requires a person to be awake and active when they would normally be asleep.
  • B. To put these issues in perspective, the US National Transportation Safety Board, which investigates crashes in all modes of public transportation, has found that driver fatigue is the most common cause of fatal-to-the-driver truck crashes (31%), and that it is implicated in 30-40% of all truck crashes.   25  ,   26  



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