GAP Index (idiopathic pulmonary fibrosis)

GAP index (Ley 2012) for idiopathic pulmonary fibrosis: gender, age, FVC % and DLCO % mapped to a stage and cited 1/2/3-year mortality.

Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.

Example

Sex
Male (Gender point = 1)
Age
68 years
FVC
60 % predicted
DLCO
40 % predicted

Result: GAP 5 points: stage II. 1-year 16.2%, 2-year 29.3%, 3-year 42.1% (Ley 2012).

The tool opens with these values already filled in. Replace them with your own.

What the result means

Stage / mortality
Stage I 0-3 (1-yr 5.6%), II 4-5 (1-yr 16.2%), III 6-8 (1-yr 39.2%); 2- and 3-year estimates per Ley 2012.

What you enter

  • Sex
  • Age
  • FVC
  • DLCO
  • DLCO cannot be performed (3 points)
How this is calculated
Points
Gender (male = 1); Age (> 65 = 2, > 60 = 1); FVC% (> 75 = 0, 50-75 = 1, < 50 = 2); DLCO% (> 55 = 0, 36-55 = 1, <= 35 = 2, cannot perform = 3).

Ley B, Ryerson CJ, Vittinghoff E, et al. A multidimensional index and staging system for idiopathic pulmonary fibrosis. Ann Intern Med. 2012;156(10):684-691. Read the source ↗

A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.

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Built by Clay Good. Source on GitHub.