Doctor Who finale watched by 10.4m as Tennant bows out

David Tennant's final outing as Doctor Who was watched by 10.4m viewers on New Year's Day, according to early overnight figures.

At the climax of the episode, a total of 10.8m tuned in to see the Time Lord regenerate into his 11th incarnation, 27-year-old actor Matt Smith.

Tennant's final words on the show were, "I don't want to go".

Smith, meanwhile, uttered the immortal line, "legs! I've got legs!" as he made his screen debut as The Doctor.

The 75-minute episode ended with the Tardis in flames, plummeting towards Earth - setting up Smith's first full episode, due later this year.

It was the highest-rated programme in its time-slot. ITV1's Coronation Street took second place, with 8.6m viewers.

However, both had lower ratings than the day's second episode of EastEnders, which attracted an audience of 11.6m at 1945GMT.

Emotions

Critics were generally appreciative of Tennant's final episode, which also marked the end of head writer Russell T Davies' tenure on the show.

The story saw The Doctor battle against his nemesis, The Master (John Simm), who took possession of the body of every human on the planet, paving the way for the return of the Time Lords - who planned to end time itself.

In The Guardian, television critic Mark Lawson likened the episode to Hamlet - a role which Tennant played with the Royal Shakespeare Company last year.

"In common with the prince of Denmark, the Time Lord from Gallifrey agonised aloud over whether it would be right to kill a man (the Master) after a painful encounter with his mother, played by Claire Bloom, whose Shakespearean roles include Hamlet's mother, Gertrude," he wrote.

Writing on Cult TV website Den Of Geek , Simon Brew felt that, by allowing Tenant to revisit the characters he met during his four-year tenure as the Doctor, Davies had given new emotional depth to the process of regeneration.

"We've never had this: 20 minutes or so for a Doctor to deal with his impending demise, with no threat to see off to get in the way.

"Usually, the emotions are dealt with afterwards, as the new Doctor gets used to his new body. Here, an outgoing Doctor got to face the ramifications of what was about to happen, and it was explored exceptionally well."

Meanwhile, in The Times, Caitlin Moran dissected Smith's debut .

"As if to remind us of how huge the Doctor Who Universe is, and how fast it gallops on, Smith wasted no time mourning his previous, dead self. Instead, feeling his delicately featured face, he started in alarm, and shouted: 'Argh! I'm a girl!'"

A preview for the new series has been made available on the official Doctor Who website.

It shows Smith facing vampire-like creatures, hitting a Dalek with a mallet, and shouting what seems set to become his catchphrase: "Geronimo!"

The trailer also hints at the return of Alex Kingston as River Song - an archaeologist who had appeared to have had an intimate relationship with The Doctor.

Her character was created by Steven Moffat, who has taken over from Davies as the head writer of the sci-fi franchise.

The new series is due on BBC One in the spring.

Late-night teens 'face greater depression risk'

Going to bed earlier protects teenagers against depression and suicidal thoughts, New York research suggests.

Of 15,500 12 to 18-year-olds studied, those who went to bed after midnight were 24% more likely to have depression than those who went before 2200.

And those who slept fewer than five hours a night had a 71% higher risk of depression than those who slept eight hours, the journal Sleep reports.

It is estimated 80,000 UK children and young people have depression.

The researchers from Columbia University Medical Center in New York looked at data from 15,500 teenagers collected in the 1990s.

One in 15 of those studied were found to have depression.

As well as the higher risk of depression, those who were set a bedtime by their parents of after midnight were 20% more likely to think about suicide than those whose bedtime was 2200 or earlier.

Those who had less than five hours sleep a night were thought to have a 48% higher risk of suicidal thoughts compared with those who had eight hours of sleep.

Teenagers who reported they "usually get enough sleep" were 65% less likely to be depressed.

Depression and suicidal thoughts were also more likely in girls, older teenagers and in those who had a lower self-perception of how much parents care about them.

Most of the parents of the adolescents in the study set a bedtime of 2200 or earlier.

A quarter set a bedtime of 2400 or later.

On average the teenagers were having seven hours and 53 minutes sleep a night - less than the nine hours recommended at that age.

Study leader Dr James Gangwisch said although it it was possible that youngsters with depression struggle to sleep, the fact that parental set bedtimes were linked with depression suggests that a lack of sleep is somehow underpinning the development of the condition.

He said a lack of sleep could affect emotional brain responses and lead to moodiness that hindered the ability to cope with daily stresses.

This moodiness could affect judgment, concentration and impulse control.

Regular exercise

"Adequate quality sleep could therefore be a preventative measure against depression and a treatment for depression," he added.

Sarah Brennan, chief executive at the mental health charity YoungMinds, said: "Enough sleep, good food and regular exercise are all essential to stay emotionally healthy.

"Nearly 80,000 children and young people suffer with depression, yet we are still failing to provide our young people with the help and support to cope with it and prevent it.

"Providing parents with information about how to look after your body, for example by getting enough sleep, and how to get help if they are worried about their teenager, will ensure problems are tackled early and prevent serious mental health conditions such as depression."