"It's an issue, we've all heard of cases such as whiplash, but there's not that much said about the psychology," IOH Wollongong's psychology services manager Sue Milne says.

A recent AAMI study involving 15,000 claims in NSW and Queensland in the past decade found that nearly 10 per cent of people involved in motor vehicle accidents suffer psychological problems.

Milne says an acute response to stress is common, and the signs of a serious problem emerge when changes in behaviour do not settle over a period of time.

"It's common for people to be disoriented, have difficulty sleeping, trouble concentrating and are anxious," Milne says.

"As it goes from days to weeks and then months, people really need to see a psychologist.

"There are signs such as turning increasingly to alcohol or withdrawing from everyday activity.

"The GP is the first point of contact, who can then refer you to a psychologist."

Chronic pain often manifests into emotional stresses, which also hinders people from returning to their everyday routines.

Anxiety and persistent pain requires a gradual approach to help people get back to their normal way of living, Milne says.

"Individuals need help to work with their families to accommodate the transition required," Milne explains.

"The thing about post-traumatic stress is that it doesn't get better by itself."

The trauma of a crash can also have an impact on bystanders and children, as well as those involved in near misses and minor accidents.

"I'm dealing with adults, but we often find that there's a child in the family whose behaviour has been affected by the parents," Milne says.

A car crash can affect people in different ways, and even police - who are trained to deal with such situations - still regularly suffer post-traumatic stress symptoms.

"There are temperament-based factors that bias our interpretation of how significant an event that occurs is," Milne says.

"For differing reasons it may be more pertinent to one person than another."

She explains this as comparing crashing an old car on the way to collecting a Lotto win, in contrast to crashing a new car on the way to a job interview.

As part of the recovery process, Milne says it's important for people to be able to get back on the road, as driving is usually part of the daily routine.

"Very often people instinctively want to avoid driving the car for fear of not controlling it in a crisis situation," she says.

Milne encourages men to also look after their mental health and talk to their GP about any concerns.

"When you look at psychological issues generally, women find it a little easier to put their hand up and say they feel they have problems."