'Concerning' changes in teenage girls' mental health
There have been "concerning" changes in the mental health of teenage girls in Scotland, a study into the behaviour of young people has suggested.
Substantially more girls than boys reported stress, nervousness, low mood and medicine use, researchers at the University of St Andrews found.
Among 15-year-olds, 54% of girls had two or more health complaints more than once a week.
Overall, however, 87% of young Scots reported high life-satisfaction.
Researchers looked at the health and well-being of those aged 11, 13 and 15 over the past four years.
The study covered their feelings and habits, including those relating to family life, school, nutrition, physical activity, body image, substance use, sexual health and bullying.
The proportion of young people who felt very happy reduced with age, from 59% of 11-year-olds to 27% of 15-year-olds.
About 10,800 school pupils took part in the survey, which followed studies carried out every four years since 1990 to provide trends over the 24-year period.
The findings revealed there had been a marked decrease in smoking among 15-year-olds over the last two decades.
There was also a reduction in alcohol consumption, with weekly drinking among 15-year-olds now below those reported in 1990.
Over the last four years, there was a decline in the proportion of 15-year old girls who reported having had sex (from 35% to 27%).
Of those 15-year olds, 24% said their first intercourse was at 13 or younger, with boys more likely than girls to report this (34% versus 16%).
Candace Currie, director of the child and adolescent health research unit (CAHRU) at St Andrews, said: "We have observed concerning changes in teenage girls' mental health, especially over the past four years.
"In 2014, 15-year-old girls are around twice as likely as boys to report irritability, nervousness and low mood.
"Moreover, for boys and girls of all ages there has been relatively little improvement in some key health behaviours such as fruit and vegetable consumption over the past 12 years.
"There are also some good news stories. For example, we have seen dramatic reductions in some risky behaviours, such as smoking, alcohol consumption and early sexual intercourse for some groups."
At school, 14% reported they have been bullied at least twice a month in the past two months.
A quarter of 13-year-old girls said they had been bullied at least once via electronic media messages in the past couple of months.
Girls were also twice as likely to be on a diet and 13 to 15-year-old girls were considerably less likely to report that they felt good-looking.
Fewer than one in five young people met the Scottish government's physical activity guidelines of at least 60 minutes of moderate to vigorous exercise every day.
And 64% reported watching television for two or more hours a day, with 65% of boys playing computer games for at least two hours a day.
The findings, which are part of an international study covering 43 other countries, will be presented at a meeting in Edinburgh attended by representatives of the Scottish government and NHS Health Scotland.
The Scottish government described the research as "worrying".
A spokesman added: "Bullying of any kind is unacceptable and must be tackled quickly, whenever it arises.
"We expect all local authorities to have an anti-bullying strategy with each school and establishment developing and implementing an anti-bullying policy in line with this.
"We invest £28m annually on improving sexual health education and improving access to contraception for young people.
"We would encourage any child or young person struggling with any issues or worries in their lives to contact ChildLine which can provide confidential advice and information by telephone and online."