Anxiety symptoms are common in cancer patients. Screening by questionnaire seems to assess anxiety symptoms adequately but discriminates abnormal anxiety inadequately. To improve this, we may need to use criteria such as disruption from anxiety, as illustrated by the impact of anxiety disorders on QOL. There seem to be few oncologic variables that could target screening for anxiety disorders.

The SDI is relevant and easy to understand. Initial psychometric evaluation was encouraging. Ongoing work to evaluate the clinical meaning and utility of the instrument and to examine the relationships between SDI scores and clinical outcomes will provide guidance about its usefulness as an assessment tool in routine oncology practice.