BACKGROUND: Shared decision-making (SDM) is the gold standard for patient-clinician interaction, yet many patients are not actively involved in medical consultations and hesitate to engage in decisions on their health. Despite considerable efforts to improve implementation, research on barriers to SDM within the patient-clinician relationship and interaction is scant. To identify potential barriers to urological patients' participation in decision-making, we developed two novel scales assessing power asymmetry (PA-ME) and embarrassment in medical encounters (EmMed). The present study validates both scales in a large sample comprising urological patients and non-clinical participants. It further examines the effects of both factors on participation preferences and decisional conflict among patients. METHODS: Data were collected from 107 urological patients at a university hospital for Urology and Urosurgery in Germany. Patients completed self-report questionnaires before and after their clinical appointments. In addition, 250 non-clinical participants provided data via an online study. All participants rated perceived power asymmetry in the patient-clinician relationship and their experience of embarrassment in medical contexts using the PA-ME and EmMed scales. Urological patients further indicated their participation preference in decisions regarding both general and urological care prior to the consultation. Afterward, they assessed the level of perceived decisional conflict. RESULTS: Factor analyses yielded power asymmetry and medical embarrassment as unidimensional constructs. Both questionnaires have good (PA-ME
α = 0.88), respectively excellent (EmMed
α = 0.95), internal consistency. Among urological patients, higher levels of perceived power asymmetry predicted lower generic participation preference (β = - 0.98, p <
.001, adjusted R CONCLUSIONS: Given their promising psychometric properties, the new instruments are recommended for routine assessment of power asymmetry and embarrassment among patients. Addressing these factors may be helpful to reduce decisional conflict and increase participation preferences. Both factors are prerequisites for a successful SDM-process and active patient engagement in health-related decisions.