Academics give little weight to Irish girls' obesity study

Thu, May 3, 2012, 01:00

A SUGGESTION in a major report on children’s health that 11-year-old Irish girls are the third-heaviest in 39 countries surveyed has been dismissed by the Irish researchers involved in compiling the data for the report.

The latest World Health Organisation report in the Health Behaviour in School-Aged Children (HBSC) study series is based on interviews with more than 200,000 young people across Europe as well as Canada and the US, in 2009 and 2010.

The study collects data and produces an international report every four years on the health, wellbeing, social environments and health behaviours of 11-, 13- and 15-year-old boys and girls.

The researchers did not weigh or measure the children but sought this information from the children and/or their schools.

Yesterday’s report indicates that rates of obesity among 11-year-old girls range from 30 per cent in the US to 20 per cent in Portugal, and just 5 per cent in Switzerland.

The Irish rate is said to be 18 per cent, or third highest.

However, Dr Michal Molcho from the Health Promotion Research Centre at NUI Galway, which co-ordinates the data-gathering in Ireland, said the figures could “not be regarded as representative”.

She said the vast majority of 11- year-olds in Ireland did not report their height and weight.

An appendix to the international report gives “rates of missing BMI data” in each country.

Ireland has the highest rate of missing data across the age groups. Some 84 per cent of Irish 11-year-olds provided no weight or height measurements, along with 74 per cent of 13-year-olds. And 56 per cent of 15-year-olds also did not provide BMI (body mass index) data.

England, Scotland and Wales also had high rates of missing BMI data across the age groups.

“The difficulty is that in some countries, such as Belgium, children are weighed in school. They aren’t weighed in school here,” said Dr Molcho.

Asked whether the Irish researchers were unhappy at the inclusion of the 18 per cent figure in the report, she said: “To some extent yes, because it is not representative.”

Yesterday’s report finds health-compromising behaviour increases as adolescence progresses, with smoking, drinking and sexual activity becoming more prevalent. An average of 26 per cent of 15-year-olds in the 39 countries are sexually active. In Ireland the figure is 22 per cent.

Smoking rates, although fairly similar at age 11, differ dramatically by the age of 15, from 25 per cent in Austria and Lithuania to 10 per cent in Norway and Portugal. The rate among Irish 15-year-olds is 13 per cent.

“We always need to be careful with rankings,” said Dr Molcho. “Though we are not as bad as Austria and Lithuania, we should remember that to have a quarter of 15-year-olds smoking is really awful, and 13 per cent is still bad.”