Cardiovascular disease (CVD) is a general term for diseases affecting the heart and blood vessels. It includes these conditions:
The ASSIGN calculator has been developed to estimate the 10 year risk of coronary heart disease, stroke and TIA.
The ASSIGN calculator combines measurable risk factors, which identify people who are at increased risk of CVD, in order to produce an overall score - the ASSIGN score. These risk factors are:
The ASSIGN calculator combines all of these risk factors by multiplication and gives a score between 0-100. The higher the score, the higher the risk of developing cardiovascular disease.
A score of 10 or more is considered to be high risk and is used to identify those who will benefit most from advice and treatment to reduce their risk.
The formula used to calculate the ASSIGN score is available in the “What is ASSIGN" section.
The number provided as the ASSIGN (v2.0) score is the estimated risk percentage of developing CVD over ten years in someone with no known CVD at the time of assessment. So, an ASSIGN (v2.0) score of 10 means a 10% risk of developing CVD over ten years. Rather than acting as a definitive prediction, the key consideration is to identify those who will most benefit from targeted interventions to reduce their risk.
A high score (≥10) does not mean the individual will definitely have a myocardial infarction (MI), angina, or stroke. It does mean that their chances are higher than someone with a score <10.
Similarly, an ASSIGN (v2.0) score < 10 does not mean that the individual will never have an MI, angina or stroke.
Individuals with an ASSIGN (v2.0) score of 10 or above should be offered advice, support and treatment to reduce their cardiovascular risk.
Further details, including associated links and resources, are included in the treatment and support pages.
ASSIGN combines readily measured factors known to lead to increased CVD risk. There are other factors which influence CVD risk, though these may be less easily measured, or influence risk through their effects on the factors included in the calculator (for example, the influence of obesity on blood pressure and cholesterol levels). These other factors include;
Though these factors are not directly featured within the ASSIGN calculator, individuals should still be provided with appropriate lifestyle advice and support relevant to these risk factors, as taking action on them can help to lower CVD risk.
Smoking in the ASSIGN (v2.0) calculator refers to tobacco use only.
Regular cigarette smokers
ASSIGN uses the average number of cigarettes per day (cigarette dose equivalent) as the measure of the smoking dose. Occasional smokers should have their cigarette consumption averaged out to a daily number.
What about ex-smokers?
The ASSIGN calculator does not include ex-smokers as a distinct category. The cardiovascular risk from smoking reduces, but continues, for several years after stopping. Previous data have suggested a halving in risk of coronary heart disease after 1 year of stopping smoking. If the person has not yet stopped smoking for 12 months or longer you may wish to calculate a score based on their previous daily usage.
For information on the early and longer term benefits of stopping smoking, refer the person to the NHS inform page on Benefits of stopping smoking.
Pipe and cigar smokers
Record the number of times per day on average that the person smokes and use the number as equivalent to cigarettes. For mixed smokers record the number of smoking events per day.
Whilst the calculator accepts inputs of systolic blood pressure up to 250mmHg, it is important that, in cases of confirmed elevated blood pressure readings, clinicians follow guidelines for treatment and onward referral as appropriate. For example: Adult hypertension referral pathway and therapeutic management: British and Irish Hypertension Society position statement
Additional resources and guidance can be found in the 'Resources for healthcare professionals' section in Treatment and support.
Enter the values for blood pressure irrespective of whether the person is on antihypertensive treatment or not. If they have previously been commenced on antihypertensive treatment, they should also have had a full cardiovascular risk assessment at that point.
You could enter pre-treatment values if available to calculate a pre-treatment score for comparison purposes.
If management of hypertension lowers a person’s ASSIGN (v2.0) score to below 10 this is not a reason to stop antihypertensive treatment.
Enter the cholesterol values irrespective of whether the person is already prescribed lipid lowering medication or not. Patients previously prescribed lipid lowering medication should have had a full cardiovascular risk assessment when this treatment was started.
If a reduction in cholesterol levels following commencement of lipid lowering medication lowers a person’s ASSIGN (v2.0) score to below 10, that is not a reason for stopping the medication in isolation.
If you have historical values for the person's cholesterol levels you could enter them to demonstrate the previous score.
(To convert from mg/dL to mmol/L – divide the mg/dL value by 38.67)
If a person's non-HDL-C >=6.0 it should be considered whether this could be consistent with FH.
FH affects up to 1 in 250 people in Scotland, confers a high-risk of early-onset cardiovascular disease and is under-diagnosed. FH is autosomal dominant and can be confirmed via a sensitive genetic screen. Family screening for close relatives of an individual (with genetically confirmed FH) is offered throughout Scotland.
Consider FH where ALL the following apply:
Where FH is suspected:
The definition of family history for the purposes of the calculator is when a person's parent or sibling has experienced coronary heart disease or stroke under the age of 60 years.
Individuals with diabetes are at increased risk of cardiovascular disease and their risk assessment and management should take account of their individual circumstances such as the duration of their diabetes and any associated end organ damage.
All individuals aged > 40 years with diabetes should be offered a statin.
Those aged < 40 years with evidence of end organ damage such as nephropathy or retinopathy and/or disease duration >20years or the presence of other cardiovascular risk factors should be regarded as having higher risk and be considered for statin therapy.
Further information, including links to relevant guidelines, are available in the 'resources for healthcare professionals' drop down in the treatment and support section.
Definition of extreme and out-of-range values
Extreme (or unusual) and out-of-range values were defined from the survey data of the Scottish Heart Health Extended Cohort (SHHEC), involving over 18000 people.
The usual range covered 95% of the original study population leaving 2.5% at either end as unusually high or low for systolic blood pressure and cholesterol values and at the top end for cigarette consumption. They are kept the same for different age and sex groups. SHHEC values table are available in a dedicated tab towards the bottom of the FAQ list.
Out-of-range values are those not occurring in the original study population.
For safety reasons, if an extreme (unusual) value is entered in the calculator then the value and the resultant score will be queried and flagged once calculated. Verify the entered value and manage according to guidelines if indicated.
As ASSIGN was originally derived from the SHHEC cohort who were aged 30-74 at recruitment, the score is extrapolated if used for individuals beyond that age range. Age is a dominant risk factor and cardiovascular risk will be high if the person is aged over 65. (More recent population data used in the recalibration process included individuals aged 40-69).
The Scottish Index of Multiple Deprivation (SIMD) is the Scottish Government's official tool for identifying areas in Scotland of concentrations of deprivation. It combines different aspects of deprivation (multiple deprivation) into a single index. Scottish Index of Multiple Deprivation 202017
The ASSIGN calculator takes the user’s post code and maps that to the SIMD score for the data zone that post code is located in. This score is displayed once all values are entered and the calculate button is activated. You can test the effect of deprivation on risk by entering SIMD scores of 5, 20 and 55, which are generated from the least, middle and most deprived fifths of the population.
The postcode I entered has not been recognised.
There may be occasional postcodes that are not recognised or do not have an SIMD score allocated. In such cases, or where the postcode is not known, leaving the data field blank will result in the calculator providing the median population SIMD score of 16.2.
What if the person does not have a postcode?
For people without a postcode e.g. people experiencing homelessness, in prison, or gypsy/travellers, it is possible to enter a substitute postcode. This substitute postcode is QQ1 1QQ which has an SIMD 2020 score of 44.6. This value is higher than the population median score.
Any enquiries regarding SIMD data zones, scores and postcodes can be directed to SIMD@gov.scot
Cardiovascular disease and mortality rates are strongly associated with socioeconomic deprivation. The ASSIGN score was developed using Scottish population data and includes SIMD, a Scotland specific deprivation score, as a risk predictor.
SIGN 149:Risk estimation and the prevention of cardiovascular disease, was published in 2017. It recommended that asymptomatic individuals should be considered at high risk if they are assessed as having a ≥20% risk of a first cardiovascular event within ten years.
However, the guideline also recognised that this threshold of 20% should be reviewed in the future to reflect the changing CVD risk within the Scottish population.
ASSIGN was recalibrated in 2024 to acknowledge changing trends in population cardiovascular event rates and risk. The recalibration process used more recent Scottish population data.
Following recalibration, Healthcare Improvement Scotland (HIS) Scottish Health Technologies Group assessed the Scottish level population impact of recalibration of the ASSIGN score, at varying thresholds. This established that, for ASSIGN (v2.0), maintaining the 20% threshold would result in many fewer people reaching the eligibility threshold for treatment.
The Cardiovascular Disease Risk Factor Steering Group therefore approved an updated threshold of 10%. This is also consistent with the current NICE 10% risk threshold applied to the QRISK cardiovascular disease risk score.
The ASSIGN (v2.0) calculator has this 10% threshold built into the outputs and there are plans to review and update SIGN 149 in 2025.
Ideally, all risk factor information for the person should be entered to obtain the most accurate ASSIGN (v2.0) score. However, if necessary, it is possible to calculate a provisional score using one or more average values to substitute for some missing values. These average values were obtained from data from the Scottish Health Survey, 2011.
After calculating a provisional score, you may wish to recalculate it, substituting higher and lower values than the average, to see if this substantially changes the person's score.
Mean values used for missing values – from the Scottish Health Survey 2011
| Age (years) | Cigarettes per day | Systolic Blood Pressure | Total Cholesterol | HDL Cholesterol | ||||
| Male | Female | Male | Female | Male | Female | Male | Female | |
| 25-34 | 12 | 11 | 125 | 114 | 4.9 | 4.8 | 1.3 | 1.5 |
| 35-44 | 14 | 13 | 127 | 121 | 5.5 | 5.2 | 1.3 | 1.5 |
| 45-54 | 17 | 16 | 130 | 125 | 5.6 | 5.7 | 1.3 | 1.6 |
| 55-64 | 19 | 15 | 135 | 132 | 5.5 | 6.0 | 1.4 | 1.6 |
| 65-74 | 17 | 14 | 136 | 139 | 5.2 | 5.7 | 1.4 | 1.6 |
| Risk Factor | Lower Bounds (inclusive) | Upper Bounds (inclusive) | ||
| Extreme Range | Usual Range | Extreme Range | ||
| Age (Years) | 25 | 30 | 74 | 90 |
| Cigarettes per day for smokers () | 0 | 0 | 40 | 100 |
| Systolic Blood Pressure (mmHg) | 80 | 100 | 200 | 250 |
| Total Cholesterol (mmol/l) | 2.0 | 3.5 | 9.0 | 12.5 |
| HDL Cholesterol (mmol/l) | 0.3 | 0.6 | 2.3 | 3.5 |
Age is the dominant risk variable in absolute cardiovascular risk assessment. Increasing age is associated with increasing cardiovascular risk, which will likely be high if the person is aged over 65.
As ASSIGN was originally derived from the SHHEC cohort who were aged 30-74 at recruitment, the score is extrapolated if used for individuals beyond that age range. More recent population data used in the recalibration process included individuals aged 40-69.
ASSIGN (v2.0)