Hundreds of thousands of children prescribed the drug Ritalin for hyperactivity might simply be the victims of lax parenting, new evidence suggests.

A British scientist has cast doubt on the existence of conditions such as attention deficit disorder (ADD), which will fuel the controversy over the increasing use of Ritalin.

Warwick Dyer, a behavioural expert, has developed a programme that focuses on the way parents behave towards their children - and claims a 100 per cent success rate over the past five years. Remarkably, he never sees the child involved, and has just one face-to-face consultation with the parents. The rest of his work is limited to a daily telephone briefing with the parents on how to treat their child.

Mr Dyer's theory is based on simple ideas such as a rigid system of rewards and sanctions for good and bad behaviour, with an insistence on politeness towards parents - and a demand that mothers and fathers control their tempers as well.

Mr Dyer said: "I am open-minded about whether ADD exists or not, but what is certainly clear is that a lot of symptoms ascribed to such disorders are in fact easily confused with basic behavioural problems that don't need to be treated with a drug.

"Parenting is not a democracy. You need to give your child what they want - love and attention - but on your terms, not theirs."

Mr Dyer's work is now the subject of a Channel 4 Cutting Edge documentary, to be broadcast tomorrow.

One in 10 children is now diagnosed with ADD or the related attention deficit hyperactivity disorder (ADHD).

Ritalin is an amphetamine with a similar potency to cocaine, and prescribing in Britain has soared one hundredfold in the past 10 years. In 1990, just 3,000 children were on the drug; today, there are 345,000 taking it, costing the NHS more than £3m a year. The drug is being given to children as young as 18 months old.

Now a growing lobby of parents, doctors and other experts is questioning whether ADD or ADHD exist.

Mr Dyer was a primary school teacher in the East End of London until he retired and set up the Behaviour Change Consultancy. He now sees about 30 families a year, and claims his techniques work with everyone, from the youngest children to teenagers.

He said: "The problem is that a lot of parents simply aren't being parents. In the last 20 years, parents have started talking to their children a lot more, but they have stopped being in control of them.

"They have tended to examine how they were brought up and reject what they thought was bad, but they haven't taken on what was good. Children are instinctively artful and will try to put themselves in control of their parents. I put parents back in control."

His "back to basics" approach worked to stunning effect with Fred and Diane from Essex, and their seven-year-old daughter, Georgina, who are featured in the Cutting Edge documentary. Georgina had been prescribed Ritalin and been diagnosed with special needs because of her appalling temper tantrums and violent behaviour. She was expelled from her first playgroup at the age of two and a half, and her parents were so desperate that last year they had decided to put her into care.

But within weeks of adopting Mr Dyer's techniques, Georgina's behaviour had improved.

Fred, who runs a wedding video business, and Diane, a civil servant, had to spend seven months in daily phone calls to Mr Dyer, where they had to describe her behaviour in detail, and accept castigations from the expert when they deviated from the sanction system.

At one point he told the couple: "It's not her fault that you can't control her. She has wrapped you around her little finger. You aren't accepting that there isn't anything wrong with your daughter."

By the end of the seven months, Georgina was having less than two tantrums a month and while her special needs diagnosis was being reviewed.

Diane said: "The change has been incredible. This has all been done without Ritalin. Before, I hated her. Now, she is a normal child. I feel guilty when I look back to how I treated her before."

Janice Hill, of the Overload Network, a parent support organisation, said: "Warwick Dyer has shown that the idea of ADHD is a myth. Children are being given a drug that has the same pharmacology as cocaine when in fact all they and their parents need are help with their behaviour.

"Doctors should stop dishing out Ritalin and start using safe alternatives, which have been proven to work."