Injury compensation lawyer Holroyd: impairment explained

Most people never need to think about impairment percentages. If your injury is serious, you probably will. The scheme's rules divide injuries by type first, threshold or not, and then, for some entitlements, by the degree of lasting impairment. This page explains both in general terms. Your own claim depends on your diagnosis and on the insurer's decisions, which can be reviewed.

The threshold line is a legal line drawn around medical facts. The diagnosis describes the injury; the scheme's definition decides which side it falls on. Sprains, strains and whiplash without nerve findings usually sit on the threshold side. Confirmed nerve damage, a tear, a fracture or a brain injury generally takes an injury beyond it. The insurer makes the call, and you can challenge it.

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, make sure they're recorded. If a diagnosis changes, make sure the insurer has the new evidence, because the classification may need to change with it. A classification made on an incomplete picture can generally be reviewed.

WPI turns a lasting injury into a percentage. An assessor examines you and rates the impairment under the guidelines that apply to motor accident claims. The number doesn't reflect how hard your life has become; it reflects measurable impairment. Even so, it can decide important questions, especially whether damages for pain and suffering are possible.

An assessment above 10% opens damages for non-economic loss and changes some timing rules as well. But many people with genuine, lasting injuries are assessed at 10% or less. That doesn't mean the injury isn't real, or that there is no damages claim. Economic loss, such as lost earning capacity, can still be claimed where the other conditions are met.

Weekly payments cover lost income for a limited time. For a serious injury, the bigger question is the future: will you be able to return to your old job, at the same hours and pay? If not, a damages claim may include past and future economic loss, provided the conditions for damages are met. That part of a claim doesn't depend on WPI above 10%.

In a serious injury claim, impairment often comes into focus well after the crash, once the injury has stabilised. The Personal Injury Commission handles medical assessment where the insurer and the injured person disagree. If you think an assessment is wrong, the steps to challenge it are set out separately, and the deadlines are short, so act promptly.

• How complete and current the evidence is
• Changes in your condition since the last report
• Whether you disagree with the result, and the deadline to say so

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 having recorded early, so the injury is properly identified in the claim rather than surfacing months later.

The most persuasive serious injury claims usually have consistent evidence: the same injuries described the same way from the first record to the last, with no unexplained gaps. That consistency comes from giving the full story every time you describe the injury. If a report leaves something out, raise it rather than letting it pass, and keep a note of when you did.

• The police report and your own account of the crash
• Every insurer decision about the injury, with its date
• Any reports prepared for the claim
• A diary of how the injury affects daily life