Dejan Ozegovic, also from U-A, looked at predications around returning to work, using the same cohort. Positive return-to-work assumptions meant people rated themselves as 'recovered' 42 percent faster than those who had more negative expectations.

Lena Holm, a Swedish researcher found that those study participants in Sweden who had low expectations of complete recovery were four times more likely to still feel symptoms of the injury six months later.

The researchers were surprised by the findings, which showed that the severity of the injury did not have an impact on the recovery times.