Elaine finds it an ordeal to leave her house each day.

Every morning she has to stop and count to ten before opening the front door of her home in Crawley to go to work.

Elaine, not her real name, suffered from agoraphobia, the fear of open spaces, for three years and it was only through intensive counselling and support she managed to overcome her condition.

She said: "I was basically stuck at home. There was nothing physically wrong with me and I looked perfectly all right until it came to leaving the house.

"I just couldn't go out because I was too frightened.

"There was nothing rational about it. I would stand by the bus stop, start to feel panicky and, before I knew it, would have to go home.

"Things started to escalate until just the thought of going out became terrifying.

"At first my friends and family found it difficult to understand but when they realised there was a real problem, they were brilliant.

"They would encourage me out and go with me. At first, it was only for small trips but they gradually got longer. I also went for counselling which helped."

Elaine is one of hundreds of people in the UK who have deep anxieties and phobias and a large amount of work is being done to help them.

Dr Andy Field, lecturer in psychology at the University of Sussex, and Dr Robin Banerjee are carrying out a three-year study into the causes of children's fears and phobias.

Children tend to develop different fears at different stages. For example, undersixes can become scared of being separated from their family, while six to eight year- olds often develop fears of certain animals.

Ten to 12-year-olds sometimes become concerned at social situations such as giving a talk, eating in public or talking in small groups.

Most will pass through the various phases naturally but, for some, the fear grows into a phobia.

A phobia is a clinically diagnosed level of fear. If a person can't be in the same room as a spider they may well have a phobia and not just a fear.

Anxiety disorders can cause people a number of different physical and psychological problems.

Some people suffer from anxiety all the time this is called generalised anxiety.

In people who suffer from panic attacks, on the other hand, the symptoms are likely to come out of the blue.

Post-traumatic stress disorder is another form of severe anxiety.

Psychological symptoms include feelings of dread and irritability and increased muscle tension.

This leads to a variety of physical symptoms such as dry mouth, shortness of breath, dizziness and trembling.

Some feelings of anxiety can be helpful, for example, by increasing a person's ability to perform in a race.

These feelings are normal. It is when symptoms are more intense or longlasting that they interfere with a person's concentration and ability to do routine tasks.

People may avoid situations that could provoke feelings of anxiety and this interference with daily living, as much as the symptoms themselves, often leads people to seek help.

Anxiety disorders are quite common, affecting five per cent of the population at any one time.

More women than men are affected. Anxiety disorders often start in people's 20s but may begin earlier and sometimes occur in older people.

The cause is not always clear. Disorders are more common in some families, suggesting that genetic factors may be important.

The aim of any treatment is to try to reduce symptoms of anxiety to an acceptable level so they no longer interfere with day-to-day living.

Doctors can help by giving a clear explanation of the symptoms and encouraging sufferers to try and identify any underlying social or emotional problems.

Other approaches to managing anxiety include therapy techniques and relaxation.

In some cases, antidepressants are prescribed in combination with non-drug treatments.

Doctors sometimes use minor tranquillisers but these are prescribed with caution because of the risk of long-term dependence.

People suffering from anxiety can help themselves by learning how to relax, doing things they enjoy and taking exercise.

Support from others is vital. More details are available from the National Phobic Society on 0870 7700 456 or go to phobics-society.org.uk