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Clinical risk stratification · GP Tools

Substance Risk Calculator.

Evidence-based risk stratification across six commonly used substances. For GP consultation support, not patient self-assessment. Evidence quality varies significantly by substance — noted per condition.

Vapes
Alcohol
Cannabis
Nicotine
Caffeine
Sugar
Evidence note. E-cigarettes have been in widespread use since ~2015. Long-term (20+ year) human outcome data do not yet exist. Most risk estimates are derived from short-term studies, animal models, in vitro data, and mechanistic inference from known carcinogens in aerosol. Risk comparisons with cigarettes are directionally valid but imprecise. Treat risk levels as indicative, not definitive.
Vaping history
Alcohol use — NZ standard drinks (1 SD = 10g alcohol)
Standard drink guide: 1 can beer (330mL, 4%) = 1.1 SD · Glass wine (150mL, 13%) = 1.5 SD · 1 shot spirits (30mL, 40%) = 1.0 SD · Pint beer (570mL, 4%) = 1.8 SD
AUDIT-C quick screen

1. How often do you have a drink containing alcohol?

Never Monthly or less 2–4×/month 2–3×/week 4+×/week

2. How many standard drinks on a typical day when drinking?

1–2 3–4 5–6 7–9 10+

3. How often have you had 6+ standard drinks on one occasion in the last year?

Never Less than monthly Monthly Weekly Daily or almost daily
Cannabis use history
Scope note. This tab covers standalone nicotine products — patches, gum, lozenges (NRT), nicotine pouches (Zyn, Velo), snus, and heated tobacco — where combustion is absent or minimal. For smoked tobacco, use the SmokeRisk tool. For vaping, use the Vapes tab.
Nicotine product use
Evidence note. Coffee/caffeine has an unusual risk profile — moderate intake has well-established protective associations for several conditions. Many cards will show as minimal/low risk and some will show protective benefit. Risk level reflects harm from excess or specific vulnerability (anxiety, pregnancy, sleep timing).
Caffeine intake
Caffeine content guide: filter coffee 240mL ~95mg · espresso shot ~63mg · instant coffee 240mL ~60mg · energy drink 250mL ~80–160mg · black tea 240mL ~47mg · green tea 240mL ~28mg
Free / added sugar intake
Free sugars = all added sugars + naturally occurring sugars in honey, syrups, fruit juices, and fruit concentrates. Does NOT include sugars in whole fruit, vegetables, or dairy. 1 teaspoon ≈ 4g. WHO recommends <6 tsp (25g)/day for additional health benefit; <10 tsp (50g) upper limit.