Depressive symptoms are associated with unrealistic negative predictions of future life events

This study examined the relationship between bias in future life event predictions and depressive symptoms. Participants varying widely in depression symptom severity estimated the probability of 40 events occurring over the succeeding 30 days. After the 30 day period, participants reported which events occurred. Optimistic/pessimistic biases were related to depressive symptoms. A non-significant optimistic bias characterized participants with low depressive symptoms whereas a significant pessimistic bias characterized participants with high depressive symptoms. Those reporting mild symptoms did not exhibit a systematic pessimistic or optimistic bias. General imprecision in predictions was positively associated with depressive symptoms. Across all participants, a reason-giving manipulation failed to decrease pessimistic or optimistic bias or improve accuracy. However, there was some evidence that participants with high levels of depressive symptoms became even more pessimistic. These findings support the claim that depression is associated with pessimistic bias, and they therefore are contrary to the strong version of the depressive realism hypothesis