Why was this study done?
Both depression and traffic injuries are important public health problems. Recovering from whiplash injuries sustained during traffic accidents often takes a long time. Symptoms of depression are common in those suffering from chronic pain. However, there is a lack of knowledge about the frequency, timing and development of symptoms of depression after whiplash injury.
How was the study done?
Researchers performed telephone interviews of all adults in the province of Saskatchewan who were either seeking health care or making an injury claim for a traffic-related whiplash injury. (Health-care providers are mandated to report patients seeking treatment for traffic injuries.) Participants completed an insurance application form shortly after the collision. They were contacted six weeks after the accident and then five more times over the year. Symptoms of depression were assessed at each interview.
What did the researchers find?
There were 5,211 participants who reported no symptoms of depression before their car accident. Of this group, more than 40 per cent developed symptoms of depression within six weeks of the injury. About 18 per cent more developed symptoms over the following year. For the majority, however, the symptoms resolved within the year. Persistent and/or recurring symptoms of depression occurred more often in the 629 participants who reported mental health problems in the six months before injury.
What are some strengths and weaknesses of the study?
Since the study was based on a large population, it included participants from all gender, racial and socio-economic groups. One weakness is that the participants self-reported previous mental health issues, which may have affected the accuracy of reporting.