Colin Tukuitonga: Lives are being saved so it must be working

One important message that could easily have been overlooked from the media coverage is that cervical screening is helping to save lives - in fact it's saved a considerable number of lives.

Between 1987 and 1997 the cervical cancer death rate dropped by 44 per cent and the incidence rate reduced by 39 per cent. And those rates are continuing to fall.

These telling statistics on our national cervical screening programme show it is having an impact where it matters - in saving lives and preventing disease.

Although internationally cervical cancer rates are dropping, our declining rates must, in part, lie with the programme's development over the past 13 years. Overall international cervical cancer incidence and death rate statistics in New Zealand, and other OECD countries with organised screening such as Finland, Sweden, Norway and Britain, have declined since the 1990s.

Furthermore, the screening programme now has policy and quality standards for all providers, and quality standards for laboratories. The programme has introduced workforce development across the sector, a nurse smear-taker training fund and an independent monitoring group provide quarterly updates on progress against nationally agreed key targets and indicators.

The most important indicators tell us the programme is working well but could do better, particularly regarding women's participation. Our enrolment rate is 99 per cent, but the participation rate is 73 per cent. While that is good by international standards (marginally behind New South Wales but better than Britain), it could certainly improve for Maori and Pacific women.

External scrutiny of our screening programme is necessary and, indeed, constructive but it must be seen for what it is: part of a process of continual quality improvement. It should also be seen in light of the New Zealand way.

We are far more consultative and participatory, particularly through including patient and consumer views, than many other countries. This is reflected in the tremendous buy-in by women into the programme, revealed by our enrolment rate. The challenge is to translate that full enrolment into full participation.

But even the world's best programmes have limitations; between 10 and 15 per cent of slides can be misread and difficulties can arise anywhere along the screening path. Hence the need for ongoing quality improvement, and for women to have smears every three years.

An audit of the programme is under way. It has been criticised for the time being taken to complete it. The aim is to find how to further improve the programme by looking at screening histories of all women who have cancer, and how this could have been prevented.

We needed a realistic schedule given the audit's size and complexities, hold-ups in accessing medical records and a larger-than-expected response from women to the audit. Put bluntly, we were faced with a trade-off between doing the job properly or quickly. No researcher would embark on a large and sensitive project in the six months originally recommended by the inquiry.

At heart, all decisions in health require some trade-off. Allowing researchers access to individuals' medical records without asking permission means research can be done more efficiently, but many patients quite rightly believe their privacy, and rights must be protected.

Steering a path through these issues is tricky and requires sure footing; whichever way you step can result in criticism. It is healthy that New Zealand has this advocacy but we cannot lose sight of what we're debating and trying to achieve through our programme.

It is part of the National Screening Unit, which also provides breast screening and advice on screening issues. The task is to consolidate these programmes and ensure ongoing quality improvement.

Independent reviewer Professor Jocelyn Chamberlain concluded in her report in May last year: "What the National Screening Unit needs most at present is a period of stability in which to settle down and have time to develop the skills it needs to maintain high-quality breast and cervical cancer screening services."

There has been debate over the unit's level of clinical leadership. It has three experienced clinical leaders who ensure effective direction and maintain links with the sector.

The unit also has competent management expertise. Dr Chamberlain stated its manager's role should not be exclusively the province of a public health specialist.

She said public health advice was certainly needed, but the person in charge must be a competent manager able to communicate effectively and strongly, not only with unit staff but with providers of screening, the groups who audit and monitor, and others with an interest in both programmes.

The debate is sure to continue but the most important message women should take from this is reassurance that the screening programme works. Its benefits speak for themselves: without regular screening, one out of 90 women will develop cancer and one in 200 will die.

Those odds are considerably improved with screening to only one in 570 women developing cancer and only one in 1280 dying if they have regular screening. Women's best protection against cervical cancer is regular, three-yearly smears.

* Dr Colin Tukuitonga is the Director of Public Health.