OBJECTIVE: To develop a short new scale to assess patient perceptions of cancer-related fatigue (CRF), and determine the beliefs and expectations of cancer patients with CRF. METHODS: To define the first version of the questionnaire a two-phase methodology was used. Firstly, initial item content was defined by integrating information from: (1) a literature review performed to identify related studies; (2) content analysis of two focus groups carried out with cancer patients; and (3) two expert meetings with oncologists. To reduce the item pool and produce the first version of the questionnaire for validation, a multicentre cross-sectional study was performed and the item pool was administered to a sample of the target population. Item reduction was based on a clinimetric approach, so that for each item in the initial pool, frequency and importance were assessed by a Likert scale and the frequency and importance product index (PI) was calculated. Item selection was based on the ordering of items based on the PI. RESULTS: The initial item pool included 75 double-items referring to mental attitude (7), social and family (15), psychological impact (12), physical functioning (12), daily life activities (12) and general opinions (17). Initial pool was administered to 238 cancer patients: mean age 57, 56% women, 30% breast cancer, 46% with anemia, average of low-to-moderate CRF intensity. 95% of sample responded at least 85% of items. Average of missing items per patient was 4.5. PI ranged from 4.9 to 12.4 and the first 40 items were selected and preliminarily assigned to six dimensions (physical, social, psychological, attitudes, daily life activities, opinions). CONCLUSION: Preliminary results from the item reduction process have led to a first version of the questionnaire with 40 items and six dimensions. The next stage will examine the psychometric properties of the new measure in a larger sample.