My mind is as clear as it used to be: A pilot study illustrating the difficulties of employing a single-item subjective screen to detect cognitive impairment in outpatients with cancer.

Oncology patients often complain that their "mind does not seem to be clear." This subjective perception, sometimes referred to as "chemo brain," may be due to situational stressors, psychological disorders, organic factors, or effects of neurotoxic medications. Cognitive decline cannot only diminish quality of life, but can also interfere with a patient's ability to make decisions regarding complex treatment issues. The current study investigated the utility of using item 11 of the Zung Self-Rating Depression Screen (ZSDS) as a cognitive screen. A sample of 61 ambulatory cancer patients completed this study. Participants were recruited from four sites of Community Cancer Care, Inc., in Indiana. A battery of cognitive instruments and psychosocial inventories was administered in a standardized order. The sample had a mean age of 58.6 years and comprised 57.4% (n=35) women and 42.6% (n=26) men. Item 11 of the ZSDS was not significantly correlated to the cognitive measures. Correlates of the perception of cognitive impairment were the Dementia Rating Scale (DRS) Attention Scale (r=-0.26, P<0.05) and the ZSDS total score (r=-0.29, P<0.05). Patients' perceptions of having a cognitive impairment determined by item 11 of the ZSDS was predicted by total score on the ZSDS (F=42.5, P<0.001), age (F=26.0, P<0.001), and score on the Stroop test (F=19.8, P<0.001). Analysis of sensitivity and specificity indicated that the single-item screen used in this study is not an accurate means for identifying oncology patients with actual cognitive impairment. We conclude that while the perception of cognitive impairment is common in cancer patients, there may be problems in interpreting the nature of these complaints, particularly in separating them from depressive preoccupation.