Does access to compensation have an impact on recovery outcomes after injury?

To the Editor: In their recent study, O’Donnell and associates1 examined the effect of compensation, and the clinically vexing problem of interaction with insurance companies, on recovery after hospitalisation for trauma in Victoria. They concluded that access to compensation might not be associated with a poor outcome per se. We agree that the relationship between compensation and health outcomes is complex, but believe there are a number of conceptual and methodological issues that undermine their findings.

First, as they note, this sample of injured people might not be representative of those making an insurance claim. In an earlier study of motor vehicle accidents in New South Wales,2 less seriously injured victims who only attended their general practitioner or spent less than a day in hospital comprised as much as 70% of those seeking compensation. Furthermore, the article by O’Donnell and colleagues provides no description of any differential attrition with respect to factors that may be associated with poorer psychosocial outcomes (such as previous psychiatric disorders), other than sex and acute hospital factors. The outcome measurement characteristics change in the course of the analyses, potentially undermining power to detect any differences. For example, the quality-of-life and disability measures become dichotomised using norms in the population for the modelling, rather than as scores in the baseline characteristics as in Boxes 2 and 3. This approach has the potential to conceal true differences between the groups because of regression to the mean and baseline differences in both groups.

The main problem relates to the possibly post-hoc exclusion of privately insured subjects from one group. We do not believe that private health insurance can reasonably be considered to be “compensation”. It can provide money to cover the cost of inpatient treatment and very limited outpatient services, but provides no more recompense and retribution for injury than Medicare. Older and wealthier Australians disproportionately hold private health insurance. This group is likely to differ on a number of factors, many of which are associated with better psychosocial outcomes. Although the authors have evaluated some demographic factors, this is likely to have introduced some potentially significant confounding. Thus there is little justification for the removal of this group from the non-compensable group alone. We would be interested to see an analysis after the removal of subjects with private health insurance from both groups. This would allow a more rigorous examination of the effect of one factor — actual insurance compensation — on recovery outcomes.