What is the test for assessing damages in a moderate or moderately severe whiplash injury?

In this decision, then Chief Justice McEachern wrote a pages 397 - 399: The assessment of damages in a moderate or moderately severe whiplash injury is always difficult because plaintiffs, as in this case, are usually genuine, decent people who honestly try to be as objective and as factual as they can. Unfortunately, every injured person has a different understanding of his own complaints and injuries, and it falls to judges to translate injuries to damages. … Perhaps no injury has been the subject of so much judicial consideration as the whiplash. Human experience tells us that these injuries normally resolve themselves within six months to a year or so. Yet every physician knows some patients whose complaint continues for years, and some apparently never recover. For this reason, it is necessary for a court to exercise caution and to examine all the evidence carefully so as to arrive at a fair and reasonable compensation. Previously decided cases are some help (but not much, because obviously every case is different) … … In Butler v. Blaylock, decided 7th October 1981, Vancouver No. B781505 (unreported), I referred to counsel’s argument that a defendant is often at the mercy of a plaintiff in actions for damages for personal injuries because complaints of pain cannot easily be disproved. I then said: I am not stating any new principle when I say that the court should be exceedingly careful when there is little or no objective evidence of continuing injury and when complaints of pain persist for long periods extending beyond the normal or usual recovery. An injured person is entitled to be fully and properly compensated for any injury or disability caused by a wrongdoer. But no one can expect his fellow citizen or citizens to compensate him in the absence of convincing evidence, -- which could be just his own evidence if the surrounding circumstances are consistent - that his complaints of pain are true reflections of a continuing injury.