Injury compensation lawyer Brereton: impairment explained

Two measurements do most of the work when an injury is serious. One is the threshold line, which separates soft tissue and some psychological injuries from everything else. The other is whole person impairment, a percentage that describes lasting impairment. Between them, they affect how long statutory benefits can run and what a damages claim, if you have one, can include.

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%.

WPI turns a lasting injury into a percentage. A doctor examines you and rates the impairment under the assessment 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.

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.

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.

There's usually no single moment when WPI is measured. Opinions may come from treating doctors, from doctors the insurer arranges, and, where the two sides disagree, from a medical assessment through the Personal Injury Commission. Timing matters, because injuries can improve or worsen for months. A lawyer can advise whether an assessment is premature before you rely on it.

• Whether every injured body part is included
• How complete and current your medical records are
• Changes in your condition since the last report

From 1 April 2023, the scheme uses the term threshold injury, which replaced the old term minor injury. A threshold injury is generally a soft tissue injury, a threshold psychological injury, or both. Soft tissue here means muscles, tendons, ligaments and similar tissue. Nerve damage is excluded, and so is a full or partial tear of a tendon, ligament, meniscus or cartilage.

Which side you're on matters. For accidents from 1 April 2023, statutory benefits for a threshold injury generally last up to 52 weeks. For accidents between 1 December 2017 and 31 March 2023, the limit was 26 weeks. If your injury is more than threshold and you weren't mostly at fault, benefits can generally continue for longer, and a damages claim may be possible.

The most persuasive serious injury claims usually have consistent evidence: the same injuries described the same way, from the hospital to the GP to specialists, with no unexplained gaps in treatment. That consistency comes from telling each doctor the full story and following treatment plans. If a report leaves something out, ask the doctor about it rather than letting it pass.

• Hospital admission and discharge records
• Imaging reports, such as X-ray, CT or MRI, where done
• Operation and specialist reports
• Every Certificate of Fitness, in order