Across conditions, clinicians can apply two consistent principles: when certainty is moderate (e.g., PDE5 inhibitors for male erectile dysfunction in SCI and MS), treatment can be presented as likely beneficial short-term; when certainty is low or very low, interventions should be presented as preference-sensitive options with transparent uncertainty, prioritizing shared decision-making and outcomes that matter to patients and partners. The gene discussed is PDE5A; the disease is myeloid sarcoma.