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  "path": "/t/decision-analysis-in-clinical-guidelines-net-benefit-nnt-nri/28682#post_4",
  "publishedAt": "2026-03-31T06:00:42.000Z",
  "site": "https://discourse.datamethods.org",
  "textContent": "RRR (Relative Risk Reduce) ＝ 1 - Relative risk ( because P(ASCVD|Tx) is less than P(ASCVD|No Tx) ),\n\nso RRR ＝ 1 - P(ASCVD|Tx) / P(ASCVD|No Tx)\n＝ ( P(ASCVD|No Tx) - P(ASCVD|Tx) ) / P(ASCVD|No Tx),\n\nP(ASCVD|No Tx) - P(ASCVD|Tx) is the ARR,\n\nso RRR ＝ ARR / P(ASCVD|No Tx),\nARR ＝ RRR * P(ASCVD|No Tx).\n\nI guess that 3% is the P(ASCVD|No Tx).\n\nso NNT ＝ 1 / (3% _35%) ≈ 100_ (NND)\n\nNNT ＝ 1 / (7% * 45%) ≈ 33 (NND)\n\nNND is number-needed-to-treat to cause 1 case of incident diabetes in 10 years according to that guideline.\n\nI guess this is how it’s used.\n\nNNT is a key term in national medical licensing examination in country I worked. But to be honest, I have never seen its use in clinical guidelines in country I worked. My experience is limited; I always assumed it was a brain teaser aimed to torment students during the exam.\n\nI am curious to hear what others think about this usage.",
  "title": "Decision Analysis in Clinical Guidelines: Net Benefit, NNT, & NRI"
}