Injury compensation lawyer Donovans Forest: impairment explained

An injury can be serious in human terms and still sit on the threshold side of the line, and the reverse can happen too. That can feel unfair. It helps to know the scheme's tests are about the type of injury and its lasting effects, not how much you've suffered. Knowing which test applies lets you and your doctors focus on the evidence that matters.

A crash can cause psychological injury as well as physical injury, and sometimes instead of it. Some psychological injuries are classed as threshold injuries; others are not, depending on the diagnosis. Anxiety, low mood, flashbacks or fear of driving are worth raising with your GP early, both for your own sake and so the injury is recorded and properly diagnosed.

Impairment is generally assessed once an injury has stabilised, meaning it's unlikely to change much with further treatment. Assessing too early can understate a serious injury. The insurer may arrange an assessment, your own doctors may give opinions, and if the insurer and you disagree about the degree of impairment, the Personal Injury Commission can carry out a medical assessment.

• How complete and current your medical records are
• Scans or tests your doctors have ordered
• Changes in your condition since the last report

The definition works by exclusion. An injury is generally threshold if it is soft tissue damage with no nerve damage and no torn tendon, ligament, meniscus or cartilage, whether the tear is complete or not, or if it is a psychological injury the scheme classes as threshold. Injuries outside that description, such as fractures, torn ligaments or brain injuries, are generally more than threshold.

Getting the classification right early helps. If you have symptoms that could point to nerve involvement or a tear, such as numbness, weakness, locking or a joint giving way, describe them to your doctor. Whether tests are needed is a medical decision. If a diagnosis changes, make sure the insurer has the new evidence, because the classification may need to change with it.

A serious injury can change more than the next few months of work. It can limit the kind of work you can do for years, or permanently. In a damages claim, that is called loss of future earning capacity, and it can be a significant part of a serious injury claim. It generally needs evidence from your doctors, your work history and sometimes vocational experts.

Whole person impairment, or WPI, is a percentage that describes how much a lasting injury affects the body as a whole. It isn't a measure of pain, and it isn't a measure of what you've lost. It's a medical assessment made under set guidelines once an injury has stabilised. In a CTP claim, WPI matters mainly for damages: non-economic loss is only available where WPI is more than 10%.

It's easy to overstate the 10% line. You don't need more than 10% WPI to claim damages for past and future loss of earnings; you need an injury that's more than threshold, another driver at fault, and not to have been mostly at fault yourself. The 10% line decides pain and suffering, and it also affects some timing rules for a damages claim.

Serious injury claims rest on medical evidence gathered over time: hospital records, imaging, operation reports, specialist opinions, and treating doctors' notes that track your progress. Your own records add the human detail. Start collecting early, keep everything in date order, and make sure each doctor knows about all your injuries, not just the one they're treating.

• Imaging reports, such as X-ray, CT or MRI, where done
• Operation and specialist reports
• Every Certificate of Fitness, in order
• Reports from a treating psychologist or psychiatrist, if any