Raw data from the study “Functioning in adult patients with idiopathic inflammatory myopathy: Exploring the role of environmental factors using focus groups”. The document shows that the most ICF categories cited by the patients were related to products or substances for personal consumption (e110), such as medication and disease-related healthy food issues in the diet, the importance of the relationship with health professionals (e355), including doctors, nurses, psychologists, and physiotherapists, accessibility to health services (e580), technological support (e115), the role of caregivers (e310), and certain problems related with the disability caused by the disease, such as muscle weakness, intolerance to physical activity, and fatigue, with their consequences on mobility. The ICF categories related to environmental factors identified here are of value for clinicians treating patients with these rare diseases, as they raise awareness of the need to reinforce the facilitating role of specific environmental factors and reduce the negative impact of others to improve the patients’ daily functioning.