Developing an emotional distress item bank for cancer patients.

Emotional distress is common among cancer patients during and after treatment. Many instruments have been used to measure emotional distress; however, none of them has emerged as a standard. Although the diversity of instruments has some merit, the lack of a common measure limits our ability to compare studies. This paper describes how we constructed a 46-item emotional distress bank. Using expert judgment, we selected a pool of items with emotional content from this six-instrument set. Rasch rating scale analysis helped us identify a set of general distress items with good model fit and a measurement gap causing floor effects. Additional items were written to augment the measure where found deficient. The resulting set of items reflects a spectrum of positive and negative affect. The measure demonstrated excellent reliability (person separation reliability = .96) and a wide range of emotional distress and was able to distinguish among levels of disease severity.