Value of a measurement
Which single test tells you most?
For 56 measurements in NHANES, how much each one improves the prediction of who dies, out of sample, among people of the same age. Grip strength and urine albumin lead; lipids add almost nothing.
Method
Each biomarker enters a Cox model as a restricted cubic spline. Models are fitted on 70% of NHANES 1999–2018 participants and scored on the other 30%. Harrell's C is computed within 10-year age bands, so age alone cannot carry the result.
"Beyond standard risk factors" adds the marker to a refitted panel of systolic BP, BP treatment, total and HDL cholesterol, smoking, diabetes, eGFR and BMI. These are associations in a general adult sample, not a screening recommendation.