Bowel-cancer screening in New Zealand will improve health cost-effectively, but won't reduce health inequalities, Otago University researchers say.
A free national programme for people 60 to 74 started being rolled out this month.
Using computer modelling, researchers found the programme is cost-effective for Māori and non-Māori, and for men and women, study senior author Professor Tony Blakely says.
"We simulated the effect of a faecal occult blood screening every two years for 50- to 74-year-olds in New Zealand and found the health gains to be large," he said.
The screening costs the New Zealand health system about $2930 (in 2011 values) per quality-adjusted life-year gained.
Prof Blakely said that, generally, an intervention costing less than about $50,000 per quality-adjusted life-year gained was considered a "good buy" for society - "so this is a 'very good buy'."
He said the reason bowel cancer screening was so effective was that it not only detected pre-cancerous lesions, called polyps, and removed them, lowering cancer rates - it could also detect cancer cases, if they developed, earlier.
But the study - published in the American journal Cancer Epidemiology, Biomarkers and Prevention - also pointed to a potential downside.
Lead author Dr Melissa McLeod said the screening achieved less health gain for Māori, because they had lower rates of getting bowel cancer in the first place.
She said it was important to increase screening rates as much as practical for Māori to lessen the inequality impacts.
At the same time, other policies were needed that offered bigger health gains for Māori, such as smoking prevention and reducing obesity.
Dr McLeod said also needed was a focus on other screening programmes that addressed cancers that occurred in high rates in Māori, such as cervical cancer and stomach cancer.