Development of a patient-reported experience questionnaire for patients with sarcoma: the Sarcoma Assessment Measure (SAM)

Purpose The aim of the study was to develop a patient-reported outcome measure for patients with sarcoma—the Sarcoma Assessment Measure (SAM). Methods and results The systematic development of SAM included a three-stage, mixed-methods study using semi-structured interviews, focus groups and questionnaires, with all stages involving patients from across the United Kingdom. In-depth interviews were conducted with 121 patients (50% male; aged 13–82; with soft tissue sarcoma (62%), bone tumours (28%) and gastrointestinal stromal tumours (10%)). Content analysis of the interview transcripts identified 1415 post-diagnosis experience statements. Experience statements were reviewed, repetition was removed and sentences were refined to form 395 ‘items’ which were included in an Item Reduction Questionnaire (IRQ) grouped as physical, emotional, social and financial wellbeing and sexuality. The IRQ was completed by 250 patients who rated each item on importance and worry. Items with a mean score above 5 (6 in the emotional domain) were removed, which reduced the list to 166 items. After review by the research team, 23 clinicians and 34 patients, 66 items were retained to test content validity. Items with a content validity ratio of < .33 were removed. Cognitive interviews were conducted with 10 patients on the final 22 items to test comprehension. Minor changes were made to four. Conclusion SAM comprises of 22 items reflecting physical, emotional, social, financial wellbeing and sexuality. This systematic process of using patient experience to develop the content of SAM will ensure that it measures what is important to patients.