Effects of yoga on anxiety, stress, sleep quality, and fatigue in women with first diagnosis of breast cancer - a randomized controlled trial

INTERVENTION: Group 1: 8 yoga sessions in a group setting for 90 min (once per week) Group 2: Wait list control group without yoga intervention for 8 weeks; after 8 weeks, patients in the control group undergo the yoga intervention (8 yoga sessions in a group setting for 90 min once per week). CONDITION: ; C50 Malignant neoplasm of breast PRIMARY OUTCOME: Group difference in change in anxiety (anxiety subscale of the DASS (depression anxiety stress scales) questionnaire) from baseline to post‐intervention SECONDARY OUTCOME: Changes in depression (DASS‐depression subscale), stress (DASS‐stress subscale), sleep quality (PSQI), fatigue (FACIT‐F), quality of life (FACT‐G), and self‐efficacy (CBI) from baseline to 8 weeks. All parameters are re‐evaluated after 16 weeks (post‐intervention measurement for wait‐list control group, follow‐up measurement for intervention group). In addition, treatment expectations are assessed at baseline (TEX‐Q). INCLUSION CRITERIA: Women with first diagnosis of breast cancer; no more than si Xmonths since diagnosis; currently undergoing treatment (chemotherapy, radiation, antibody, and/or antihormone therapy); self‐reported presence of anxiety, sleep disturbances, and/or fatigue; sufficiently good general health to participate in the intervention (assessed by the treating physician); sufficient knowledge of German language to answer the questionnaires and follow the lessons; written informed consent for study participation and data collection.