NOHSAC Report

Executive Summary

This review provides a comprehensive international evidence-based review of methods and systems used to measure occupational disease and injury (excluding New Zealand) and assess the ability of surveillance systems to measure changes in work methods and work organisation. The method involved a literature review and survey of existing approaches.

The workplace is a significant and consistent contributor to injuries and illness and associated fatalities. Worker health is therefore fundamental to public health and to a healthy and productive society. Tracking systems form the cornerstone of injury and illness surveillance. Surveillance systems involve the ongoing and systematic collection, analysis, and interpretation of information so that appropriate preventive action may be taken.

Occupational surveillance systems have undeniable value and hold considerable potential for prevention approaches. However, most current systems rely on an unsatisfactory patchwork of data and systems.

The utility of any surveillance system rests on its ability to capture data from the largest possible proportion of the target population, and for that data to incorporate the widest possible range of potentially relevant variables. Data-driven systems have been built to take opportunistic advantage of information collected for other purposes. Concept-driven systems are rare, but stand as beacons of success for others to aspire to.

Integrated occupational surveillance systems are based on sound theoretical principles and have high data capture rates. They use multiple data capture methods that are integrated into the workplace, healthcare, and compensation/insurance and social security systems. Equal focus is placed on occupational disease and injury, thereby avoiding arbitrary divisions. Work environment is monitored, in addition to cases or incidents. Standardised definitions are used, allowing comparisons within and between systems. Comprehensive sets of indicators are used, with free text fields to augment. Bias is minimised. Data capture emphasises core attributes of sensitivity, specificity, representativeness, timeliness, simplicity, flexibility and acceptability, and includes reliability checks.

The most effective occupational surveillance systems have two unique characteristics. They are run within independent units or services, with the principal mission to provide epidemiological excellence. They also use independent oversight and expert advice. It is vital to separate the collection and interpretation of data from the commercial, political, or social agendas of organisations or groups that may collect it.

The most important conclusion is that we need to do better at occupational surveillance in order to realise the potential of these systems. None of the existing occupational surveillance systems in use around the world stands out as a shining example, but the ones that most closely approach the ideal are those with dedicated services that are independent, and charged with the mission to champion this cause. However, this alone is not sufficient. The system must also be comprehensive and emphasise occupational illness in addition to occupational injury. Of the systems reviewed, the Finnish approach is the one that currently most nearly attains these criteria, and it seems that New Zealand could learn a substantial amount from this model.

The following recommendations are offered by the reviewer, while acknowledging that some of these have resource implications. These recommendations outline a high-quality occupational surveillance system.

Recommendation 1. Establish an independent Epidemiology Bureau

There should be an independent unit providing an epidemiology department with overall responsibility for surveillance systems. This epidemiology bureau should have an appropriate management structure that is entirely independent of any stakeholders or organisations that may hold their own agendas in order to avoid bias. It should be funded by contributions from stakeholders, including but not limited to the Ministry of Health, the Ministry of Social Development, the Accident Compensation Corporation, and private health insurers or underwriters.

Core tasks would be to:

Recommendation 2. Establish an Expert Group

There should be an expert group, whose principal function is to advise the epidemiology bureau. Membership should be time-limited, allowing staged turnover to maximise fresh ideas. This group would advise the epidemiology bureau on key topics, including:

In addition, the expert group would function as an expert panel in the development of guidance on specific occupational health topics

Recommendation 3. Establish an integrated Concept-driven Surveillance System

The core of this should be a national database that includes all occupational injuries and disease. This could be modelled on the Finnish equivalent. The epidemiologist(s) would be required to integrate data capture into the workplace and the ACC and health systems. The core database would be augmented with multiple data capture techniques, with consideration given to using a mixture of techniques, targeted carefully at specific issues. This might include sentinel systems, expert opinion, surveys, and laboratory reports, for example.

Recommendation 4. Adopt best practice principles for surveillance

The key features of high-quality surveillance systems are outlined in detail in this review. It needs to be emphasised that surveillance systems rapidly deteriorate into ineffective systems when compartmentalised or fragmented. The best practice requires a “systems approach”, without cutting corners. An expert group needs to be consulted to ensure that the surveillance system will result in useful outputs and can be continuously improved.

Recommendation 5. Publish surveillance data

Undertake wide dissemination of information on a regular basis.

Recommendation 6. Use the surveillance system to evaluate the effectiveness of interventions

The surveillance system should be used to evaluate the effectiveness of interventions, such as prevention initiatives and improvements in work methods and work organisation. However, this can only be achieved if the system is sensitive to change. This will be contingent on development of an integrated surveillance system, built on the recommended principles of best practice outlined in this review.