Five judges, headed by the master of the rolls, Lord Woolf, are expected to raise the sums awarded by the lower courts in eight test cases, increasing some by as much as 100%. Their judgments will then become guidelines which will boost awards in future cases.
The outcome will not affect damages for loss of earnings and the cost of long-term care, which make up the bulk of£1m-plus compensation payouts for the most disabled accident victims.
The judges will look only at the element which is hardest to compensate in financial terms - the effect of the victim's injury in terms of pain, limitations on bodily capacity and inability to enjoy leisure activities.
Insurers say the result will inevitably be higher premiums for motorists and employers.