Risk-benefit reasoning is the systematic process NPs use to weigh potential therapeutic benefits against potential harms when making clinical decisions. This framework applies to diagnostic testing, pharmacotherapy, surgical referrals, and screening decisions. Key concepts include: Number Needed to Treat (NNT) — the number of patients who must be treated for one to benefit (lower = better); Number Needed to Harm (NNH) — the number treated before one experiences an adverse event (higher = better). When NNT < NNH, the treatment benefit outweighs risk. Absolute risk reduction (ARR) provides a more meaningful assessment than relative risk reduction (RRR) because RRR can make small absolute benefits appear large. For example, a drug reducing MI risk from 2% to 1% has an impressive 50% RRR but only a 1% ARR (NNT = 100, meaning 100 patients treated for 1 year to prevent one MI). Patient-centered risk-benefit analysis incorporates: disease severity and natural history, treatment efficacy (NNT), treatment risks (NNH for specific adverse effects), patient preferences and values, quality-of-life impact, cost considerations, and alternative options including watchful waiting. Decision aids and shared decision-making tools...