Limpets' breath test
The work has nothing to do with shellfish, however, as Limpets is the nickname given to Stronsay folk by other Orcadians and refers to the island's code name during the Second World War.
Six pupils from Stronsay Junior High School and their teacher Bob Tateson won #163;2,000 for their school, which has invested the money in a computer scanner and is extending the library's non-fiction section, and donated #163;500 to the National Asthma Campaign.
The students - Craig Cooper, Damian Stout, Gemma Cooper, Lorna Shearer, Lindsey Miller and Pam Shearer - decided to research asthma as a follow-up to a similar survey carried out in 1994 by Orkney's chief medical officer.
The team first tried to find out how common asthma is in the rest of the UK - it affects7.5 per cent of children aged five to 15 and 4.5 per cent of the whole population.
A report sent to schools by the Scottish Office Health Department attributed high prevalence of asthma to air pollution. But the Stronsay pupils were determined to challenge this commonly-held assumption because their own island, despite being a green haven, has a high incidence of asthma - 46 sufferers out of a population of 354 people. That is 13 per cent compared with 2.4 per cent (13 out of 533) on the neighbouring island of Sanday.
The students studied the cause and effect of asthma, and measured the lung capacity, peak air flow from them, age, sex, height and weight of fellow students to see if these differed between sufferers and non-sufferers. For instance, they charted the lung capacity by asking subjects to take a deep breath and blow as much air as they could into a 5-litre measuring bottle filled with water, held upside down in a sink of water. The experiment seemed to show that having asthma was not related to how much air the subject's lungs could hold. It seem to indicate, however, that children's lungs get bigger as they get older.
The results of the investigations were put on a database - 172 records each with 33 fields with 5,676 facts - enabling the students to examine the statistics for their island. They wrote to GPs throughout the Orkneys to gather comparative statistics from 13 islands.
The students then devised a model to show the unlikely probability of Stronsay's high incidence of asthma being caused by random chance. For this they used a grain of barley for every person in Orkney. About 18,835 grains of white barley were weighed out representing all those people without asthma; 1,156 grains were stained black with iodine to represent all those with it; and 354 holes were cut in an old rubber mat, one for every person on Stronsay. The mat and the barley were placed in a tray and all the spare barley was brushed away until each hole had only one grain of barley. The number of black grains was recorded each time and the experiment was repeated 100 times. Forty-six black grains never occurred, the nearest was 39. So the chances of having 46 asthmatics on the island were more than 100 to 1 against.
They then compared incidences of various factors among asthma sufferers and non-sufferers, such as their sex, whether the family burned peat or coal as fuel, or whether they had dogs or cats at home.
The Health Matters judges were impressed with the presentation of the project, the use of information technology and the photographs, which the students had taken and developed themselves. The young scientists of Stronsay school had produced outstanding research.
For a pack on the 1997 SmithKline Beecham health matters School Awards, contact Caroline McGrathMarian Essery, The Runnymede Centre, Chertsey Road, Addlestone, Surrey KT15 2EP. Tel: 01932 567243 fax 01932 570161
Caroline McGrath is an Association for Science Education field officer and runs the SmithKline Beecham Health Matters School Awards on behalf of the ASE