Screening: “Huge potential” but cautions - expert
NATIONAL SCREENING UNIT
Monday 14 April
“Huge potential” of screening but proceed with caution - screening expert
Screening is the adolescent of the health care family – growing rapidly but still sorting out identity issues. That was the message today from the chair of the National Screening Advisory Committee to a symposium being hosted by the National Screening Unit in Wellington.
Professor Alistair Woodward, who is also head of the School of Population Health at Auckland University, told delegates that while present screening programmes are ‘good news stories’ with reductions in deaths from breast and cervical cancer since screening programmes began, the future of screening is not at all clear.
“There’s been a rapid increase in activity in screening in the last few years – not just in the national screening programmes but also in the level of ‘opportunistic’ screening by staff in general practice, clinics and hospitals for conditions like diabetes, hepatitis B and chlamydia. There are even moves into social areas like family violence screening,” Professor Woodward said.
“There’s a big appetite for screening from the public and health professionals who see it – and rightly so – as an effective way of detecting problems early and reducing harm and deaths.
“But screening is not straightforward. It isn't necessarily helpful to find disease early. Screening may save money, but it might not. The screening test itself is a small fraction of the total cost of screening. On top of all this, funding is not endless and decisions will have to be made, in the face of an increasing number of competing options, about where to draw the line.”
Professor Woodward said that in the future, ‘citizens’ juries’ may help decide which conditions get screened for.
“With competing demands for screening, we also need to find ways of measuring the success of different forms of screening. Originally reduction in deaths was the gold standard by which we measured success in screening for conditions like breast and cervical cancer. Now, with programmes like screening newborns for hearing, that measure is no longer relevant and we need new tools to judge the success of such programmes.
He said everyone in the field should also be careful not to oversell screening.
“I am wary of what I call the ‘warrant of fitness fallacy’. That is, that screening is seen as some sort of six-monthly check of bodily mechanics which then offers a clean bill of health, or indicates where repairs are needed. Unfortunately the human body is a lot more complicated than a motor car. It is more difficult to spot the causes of ill-health, and as for the repairs, usually you can't simply whip in a new spark plug.
“So while screening has clear benefits for all New Zealanders, it is still the teenager of health care: a bit unsure of its role, tending to be rather unco-ordinated and sometimes in the newspapers for the wrong reasons.
“But screening does have huge potential and the rate of expansion is impressive. Screening has a big future, but we should proceed with caution,” Professor Woodward said.