Hsi Calculator - Score and Interpret

The hsi calculator turns the two-question Heaviness of Smoking Index into a 0-6 dependence total and labels the result as Low, Medium, or High. It is built for current daily smokers who want a quick, validated read on nicotine dependence before a clinic visit, a quit attempt, or a check-in with a quitline.

• • Self check before a primary care visit: Answer the two HSI questions at home so the conversation starts with a shared dependence number rather than a yes-or-no smoking question.
• • Brief screening in a clinic, pharmacy, or community program: Flag dependence in under a minute, then refer anyone in the Medium or High band to cessation support.
• • Re-screening after a behavior change: Retest the HSI after a quit attempt, a cut-down plan, or a switch to nicotine-replacement therapy to see if the dependence score has shifted.
• • Personal reflection on nicotine dependence: Treat the score as a private, structured way to think about how soon the first cigarette of the day arrives and how many are smoked on a typical day.

The HSI keeps the original Kozlowski wording for both items, so the score can be compared with the 1994 validation papers, primary-care protocols, and population surveys. A Low band is not the same as a safe level of smoking, and a High band is a starting point for a clinical conversation, not a label. The calculator is informational; the result should sit alongside clinician judgment and any local cessation resources.

For a broader look at dependence patterns that go beyond nicotine, the Addiction Calculator keeps the same brief-screen pattern across several common substances.

The hsi calculator works in three steps. It scores time to first cigarette and cigarettes per day independently, adds them, and applies the Low, Medium, and High dependence bands from the original paper.

• ttfc: Time to first cigarette after waking on a typical smoking day. Scored 0-3 using the original HSI response options: After 60 min (0), 31-60 min (1), 6-30 min (2), Within 5 min (3).
• cpd: Cigarettes smoked per day, scored 0-3 using the original HSI response options: 10 or fewer (0), 11-20 (1), 21-30 (2), 31 or more (3).
• context: Optional flag for the interpretation note. Choose 'General adult smoker' or 'Pregnant or under 18'. It does not change the HSI score or the dependence band.

Both per-item scores are 0-3 integers from dropdowns, so the total is a clean integer in the 0-6 range. The result panel shows the per-item scores, the total, the dependence band, and a one-line interpretation note. The context flag only changes the closing note, not the score or the band.

The dependence bands follow the original HSI cutoffs: 0-2 is Low, 3-4 is Medium, and 5-6 is High. The calculator never invents a band outside that range and never rounds the per-item scores, so the total is always reproducible from the two selected items.

According to Kozlowski et al., Drug and Alcohol Dependence, 1994, the HSI is the sum of two questions (time to first cigarette and cigarettes per day), each scored 0-3, for a 0-6 total

When a clinical conversation also covers daytime sleepiness or sleep-related risk, the Epworth Sleepiness Scale Calculator applies a similar total-band read to a different brief screen.

Four concepts matter for reading the hsi calculator the way the original authors intended. Naming them keeps the score from being read as a diagnosis.

The single most important distinction is dependence versus diagnosis. A High HSI on its own does not meet DSM-5 criteria for tobacco use disorder, even though the same HSI wording is used in primary care, research, and population surveys. The two HSI questions also overlap with the six-question Fagerstrom Test for Nicotine Dependence, which is why the HSI is often described as a brief two-item version of the FTND.

Many adults who smoke also drink, and the Alcohol Units Calculator uses the same per-drink unit logic to keep alcohol use comparable across visits and quit attempts.

The form is a two-question HSI questionnaire plus a context flag. Each question should be answered for a typical smoking day, not for a single unusually heavy or unusually light week.

1. 1 Pick the time to first cigarette: Choose the response that best matches a typical smoking day: After 60 min (0), 31-60 min (1), 6-30 min (2), or Within 5 min (3).
2. 2 Pick the cigarettes per day: Select the response that matches the number of cigarettes smoked on a typical day: 10 or fewer (0), 11-20 (1), 21-30 (2), or 31 or more (3).
3. 3 Pick the context flag: Choose 'General adult smoker' or 'Pregnant or under 18'. The flag only changes the closing interpretation note and does not change the HSI score or band.
4. 4 Read the HSI total and the band together: Treat the total and the dependence band as a set, then look at the per-item scores to see whether time to first cigarette or cigarettes per day is driving the result.
5. 5 Pair the result with a next step: Use the band to decide whether to talk with a clinician, contact a quitline, ask about nicotine-replacement therapy, or simply track the score over time.

A reader who has their first cigarette 6-30 min after waking and smokes 11-20 per day enters ttfc = 2 and cpd = 1. The hsi calculator returns HSI Total 3, Dependence Band Medium, with the standard adult note about cessation support.

Using the hsi calculator the way the original authors and the CDC cessation guidance designed it gives several practical benefits over a single yes-or-no smoking question.

• • Two-question brevity: The HSI fits in a 30- to 60-second screen, which is why it is used in primary care, pharmacies, and quitline intakes.
• • Validated 0-6 total: The per-item scoring and the Low, Medium, and High bands come from the 1994 Kozlowski paper and have been reused in studies for three decades.
• • Per-item and total readout: Seeing TTFC and CPD side by side shows whether morning urgency or daily volume is driving the dependence band.
• • Clear band-based framing: The band label is easier to act on than a raw 0-6 number and lines up with CDC cessation-support messaging.
• • Screening, not diagnosis: The result is framed as a brief screen and a trigger for support, not a clinical label.
• • Re-screening friendly: The same HSI wording can be repeated before a quit attempt, during nicotine-replacement therapy, and after a behavior change to track the dependence score over time.

The tool pairs well with fuller cessation support when the band is Medium or High. The per-item scores also make it easier to choose which behavior to discuss first, since a High TTFC score with a Low CPD score points toward morning cravings while a High CPD score with a Low TTFC score points toward daily volume.

Pairing the hsi calculator with a parallel WHO screen is a common workflow, and the Audit C Calculator handles the three-question alcohol side of that annual check-in.

The result depends on the two items entered and the band applied. Small changes can flip the band, especially near the Low/Medium and Medium/High boundaries.

• • The HSI is a brief screen, not a clinical assessment. A High band on its own does not diagnose tobacco use disorder and should be followed by a clinical conversation or a fuller assessment.
• • The two HSI items were developed for current daily smokers. People who have recently quit should retest after a stable period, and people who smoke only on some days should treat the result as a directional read rather than a steady-state score.
• • The cigarettes per day question counts cigarettes, not packs. Hand-rolled cigarettes, mini-cigarettes, and cigarillos each count as one cigarette even when the nicotine yield is different.

The band label is read against the original HSI cutoffs, not against a personal goal. The context flag only adds the relevant interpretation line, so the HSI score itself stays comparable across adult, pregnant, and adolescent contexts. A High band is also not a personal failure; the CDC cessation guidance treats it as a clinical trigger for evidence-based support, including counseling, nicotine-replacement therapy, and prescription options where appropriate.

According to CDC Tips From Former Smokers, adults who smoke benefit from evidence-based cessation support, and brief screens like the HSI are a way to flag dependence in clinical and community settings

According to Kurti et al., Experimental and Clinical Psychopharmacology, 2016, the HSI was a stronger predictor of late-pregnancy quitting than cigarettes per day alone in a 289-woman cohort

For a same-day estimate of the alcohol in the bloodstream after a recent drinking session, the BAC Calculator turns a drink count into a blood alcohol content reading.