Calculators Calculators
OST (Osteoporosis Self-assessment Tool)
Osteoporosis risk screening for DEXA referral.
Simple age + weight formula. Validated in postmenopausal women. Universal.
How it works
What it measures
Osteoporosis risk to decide whether to request a DEXA scan, using only two data points: weight and age.
Scoring
Score = weight (kg) − age (years). Lower score (older, lighter), higher risk.
The items
1
Weight · in kg
2
Age · in years
Interpretation
> 1 Low risk
DEXA not indicated by OST. Reassess at 5 years or if risk factors appear.
−3 to 1 Intermediate
Consider DEXA if ≥1 factor: steroids, FH hip fracture, prior fracture, low BMI, smoking, early menopause.
< −3 High risk
DEXA indicated. Apply FRAX if T-score ≤ −1; consider treatment if T ≤ −2.5 or fragility fracture.
Crude triage; cutoffs shift by sex (+1 in men). Does not replace risk-factor assessment or FRAX/DEXA.