Please note that at this current time, these services are not available for use in a live environment and must not be used. The following information is made available in advance of go-live
Background
Information about the research and algorithms that resulted in QRISK3, as well as the free to use Web site can be viewed https://qrisk.org
QRISK Services
QRISK services use Endeavour Predict services which consist of
- A set of Web based APIs for submitting requests for a prediction and receiving a response, the response including a risk score, a heart age , and information relating to the calculation of the scores.
- A set of FHIR APIS to enable system suppliers to know which Snomed-CT concepts should be used when deriving information from records. These are part of the Endeavour information model services
- A REST API for deriving a Townsend deprivation score from a post code, the Townsend score being then submitted as part of the QRISK request payload.
- Source code repositories of open source code used by 1) and 2) and 3)
Use of health data for generating variables
Systems may have access to longitudinal health records, in particular those held in General Practice. In that case those systems may elect to query the health record data in a way that provides likely values for the variables, passed as parameters, used in the QRISK algorithm.
In this case, a set of query criteria and rules are applied to the record entries and the values of the variables derived. These are then presented to a user for confirmation, or amendment before being submitted as a set of parameters to the function via an API.
It is strongly recommended that for any individual decision, or potential entry of the risk score in the record, that each set of assumptions are confirmed byt the user. However, purely automated calculations may be used for population based risk stratification in order to plan interventions.
Reference date
Scores may be calculated retrospectively. The reference date (current date or past date) is used for all values i.e. what those values were on the reference date. For example when looking for dates within 6 months this means 6 months prior to a reference date
Patient inclusion criteria
This section documents the criteria for a person suitable for the application of QRISK3
All dates are relative to the time at which the algorithm is applied to the patient and is referred to as the reference date.
- Aged between 25 and 84 inclusive at the reference date
• Free from a diagnosis of cardiovascular disease (qr: group 411 see below) on or before the reference date
Independent variables as function parameters
QRISK® operates as a function whose parameters represent independent variables. The API accepts these arguments as JSON key value pairs (or lists) in the payload of the request.
The values of those variables, when used in the algorithm are derived in one of two ways
a) By direct entry by a user
b) By a query of a health record.
When passed into the algorithms as arguments to the function, the values are presented either as a double, an integer, a boolean 1 or 0, or a character. The client must convert to these formats before submitting in the payload using the maps as documented below.
If variables are unknown (missing) or their values are out of range, the algorithm may either reject the request, provide a default value for the parameter, or adjust an out of range value to an outer limit. The way the algorithm handles these parameters are documented below in the relevant parameter.
Health records contain entries that have a property of a main concept (e.g. a systolic blood pressure), an effective date (the date of relevance to the observation or action), and a numeric value. For the purpses of these rules, concepts are grouped into named sets
Each concept set is universally identified with an IRI (which is in the format of a URL) and the base iri namespace for Q concept sets is http://apiqcodes.org/qcodes#. When used in the below tables, for clarity, the iri prefix "qr:" is used.
Input parameters needed to calculate a QRISK3® score and their handling are as follows:
Row ID
Optional Integer.
Used by the client as a reference when a batch API is used. i.e. returned by the result. It has no scope beyond the API request/response
Age
Mandatory Integer. Age of the person in years at the reference date
Gender
Mandatory Character 'M' or 'F'.
Male or female.
Binary values only accepted. QRISK does not have information on transgender or indeterminate gender risks at this stage. It is the responsibility of the requester as to whether to apply the higher risk M gender e.g. For Trans Women and to explain the rationale.
Cardiovascular disease
Optional Boolean 1 or 0
Cardiovascular disease prior to the reference date
This is an inclusion criteria and should therefore be 0. The request will be rejected if this is set to 1
Default handling of unknown is 0
Atrial fibrillation
Optional Boolean 1 or 0.
Atrial fibrillation at any time prior to reference date.
QRisk does not differentiate a single one off AF event from chronic or intermittent AF. Clinical interpretation may be required for those with a single event many years ago.
Default handling of unknown is 0
Rule
Observation
concept qr:24
effective date < reference date
| Code group | Maps to |
|---|---|
| qr:24 | 1 |
Atypical anti psychotics
Optional Boolean 1 or 0.
Second generation ‘atypical’ antipsychotic - prescribed two or more issues in the previous 6 months (includes amisulpride, aripiprazole, clozapine, lurasidone, olanzapine, paliperidone, quetiapine, risperidone, sertindole, or zotepine)
Default handling of unknown is 0
Rule
Medication request
medication in qr:1169
effective date range -6 to 0 months relative to reference date
Count(entries)>=2
| Code Group | Map |
|---|---|
| qr:1169 | 1 |
Systemic corticosteriods
Optional Boolean 0 or 1
Systemic corticosteroids –prescribed two or more issues in the previous 6 months
Rule
Medication requests
medication in qr: 1194
effective date range -6 to 0 months relative to reference date
Count(entries) >=2
| Code Group | Map |
|---|---|
| qr:1194 | 1 |
Migraine
Mandatory boolean 0 or 1
Diagnosis of migraine prior to the reference date
Rule
Observation
concept in qr:39
effective date <= reference date
| Code Group | Map |
|---|---|
| qr:39 | 1 |
Rheumatoid arthritis
Mandatory boolean 1 or 0
Diagnosis of Rheumatoid arthritis prior to the reference date
Rule
Observation
concept in qr:58
effective date <=reference date
| Code Group | Map |
|---|---|
| qr:58 | 1 |
Chronic renal disease
Mandatory boolean 1 or 0
Chronic renal disease at any time prior to the reference date
Rule
Observation
concept in qr:322
effective date <= reference date
| Code Group | Map |
|---|---|
| qr:322 | 1 |
Severe mental Illness
Mandatory boolean 1 or 0
Diagnosis of severe mental illness (psychosis, severe depression, manic depression, schizophrenia) at any time prior to the reference date
Rule
Observation
concept in qr:3187
effective date <=reference date
| Code Group | Map |
|---|---|
| qr:3187 | 1 |
Systemic lupius erythematosis
Diagnosis of systemic lupus erythematosis at any time prior to the reference date
Rule
Observation
concept in qr:70
effective date <= reference date
| Code Group | Map |
|---|---|
| qr:3187 | 1 |
Treated hypertension
Mandatory boolean 1 or 0
Diagnosis of hypertension at any time in the patient’s records AND On antihypertensive treatment if 1 or more medication requests within 6 months prior to the reference date.
Rule
Observation
concept in qr:21
effective date <= reference date)
AND
Medication request
medication in (medication qr:740 qr:751 qr:759 qr:760 qr:765 to be revised)
effective date range -6 to 0 months relative to reference date
| Code Group | Name | Map |
|---|---|---|
| qr:21 | Hypertension | 1 |
| qr:740 | Thaizides | 1 |
| qr:751 | Beta blockers | 1 |
| qr:759 | ACE inhibitors | 1 |
| qr: 760 | Angiotensin ii receptor agonists | 1 |
| qr:765 | Calcium channel blockers | 1 |
Body mass index
Optional double
The most recently recorded body mass index for the patient recorded prior to the reference date recorded in the last 5 years.
Rule
Observation
concept in, qr:200
effective date range -5years to 0 time relative to reference date.
Most recent entry
Handling of out of range values by the calculator
<18 is set to 18, >47 is set to 47
| Code Group | Name | Map |
|---|---|---|
| qr:200 | Body mass index | 1 |
Diabetes Category
Mandatory integer 0 or 1 or 2
Categorical variable to denote no diabetes, type 1 diabetes or type 2 diabetes diagnosed at any time prior to the reference ate
Rule
Observation
concept in qr:1913,qr:2411
effective date <=reference date
Most recent entry
| Code Group | Name | Map |
|---|---|---|
| qr:1913 | Type 1 diabetes | 1 |
| qr:2411 | Type II diabetes | 2 |
Ethnicity
Mandatory integer between 0 and 17
Ethnic category
Rule
Patient
Ethnicity in (qr:17071, qr:17072, qr:17073, qr:17074, qr:17075, qr:17076, qr:17077, qr:17089, qr:17079, qr:17080, qr:17081, qr:17090, qr:17985, qr:17086, qr: 17087)
| Code Group | Name | Map |
|---|---|---|
| null | 0 | |
| qr:17071 | White british | 1 |
| qr:17072 | White Irish | 2 |
| qr:17073 | Other White Background | 3 |
| qr:17074 | White & Black Caribbean | 4 |
| qr:17075 | White & Black African | 5 |
| qr:17076 | White & Asian | 6 |
| qr:17077 | other mixed | 7 |
| wr:17089 | Indian | 8 |
| qr:17079 | Pakistani | 9 |
| qr:17080 | Bangladeshi | 10 |
| qr:17081 | Other Asian | 11 |
| qr:17090 | Caribbean | 12 |
| qr: 17083 | Black African | 13 |
| qr:17091 | Other Black | 14 |
| qr:17985 | Chinese | 15 |
| qr:17086 | Other ethnic group | 16 |
| qr:17087 | Not stated and not classified | 17 |
Family history of Coronary heart disease
Optional boolean 0 or 1 default 0
Family history of coronary heart disease in a first degree relative under the age of 60 years recorded before the reference date
Rule
Observation
concept in qr:404
effective date <= reference date
| Code Group | Name | Map |
|---|---|---|
| qr:404 | Family history of coronary heart disease | 1 |
==== Total cholesterol HDL ratio Optional double
The most recent ratio of total serum cholesterol/HDL recorded in the last 5 years. The ratio is either directly directly recorded (eg using group 405) or can be calculated using total cholesterol divided by hdl.
Note that the person must either have a ratio or both a total and hdl value.
Rule
Observation
concept in qr:16 (total cholesterol TC)
effective date <=reference date - MOST recent as TC
Observation
concept in qr:367 (HDL)
effective date <=reference date - MOST recent as HDL
Observation
concept in qr:405 (CHDL ratio)
effective date <=reference date MOST recent as TCHDL
If TCHDL effective date > TC effective date OR TCHDL effective date >HDL effective date
then value= TCHDL numeric value
else if TC effective date > TCHDL AND HDL effective date >TCHDL effective date
then value = TC / HDL
else
value = null
Handling of out of range values by calculator <1 is set to 1, >12 is set to 12
Smoking category
Optional integer 0, 1 ,2 ,3 or 4 default 0
Category variable The most recently recorded smoking status with 5 levels
This categorisation has one group for ex-smokers rather than trying to distinguish between ex light, ex moderate and ex heavy smokers.
This categorisation does not distinguish between cigarette/cigar and pipe smokers
Special consideration should be given to records that contain both numeric values for the number of cigarettes smoked, and concepts that categorise into light moderate or heavy.
The logic on non smoker is that from the entry of the most recent if it has a numeric value or if there other codes on the same day with numerics take the numeric value on the same day as the most recent, unless the most recent is non smoker
Rule
Observation
concept in (qr:2239 -(NONE), qr:2238 (EX) , qr:2244 (LIGHT), qr:2242 (MODERATE), qr:2243 (HEAVY)
effective date <=reference date
numeric value is NULL
as NOVALUE
Observation
concept in (qr:2239 -(NONE), qr:2238 (EX) , qr:2244 (LIGHT), qr:2242 (MODERATE), qr:2243 (HEAVY)
effective date <=reference date
numeric value not null
as HASVALUE
Sort by effective date time descending.
If most recent is NOVALUE (as MOSTRECENT)
if most recent HAS VALUE effective date= MOSTRECENT effective date // non value and value on same date!
then value is numeric map of HASVALUE numeric value
else
value is concept map of NOVALUE concept
else if most recent is HAS VALUE
value is numeric map of MOSTRECENT numeric value
else
no record value is null
Concept set Map
| Code Group | Name | Map |
|---|---|---|
| qr:2239 | None smoker | 1 |
| qr:2238 | Ex Smoker | 1 |
| qr:2244 | light smoker | 2 |
| qr:2242 | Moderate smoker | 3 |
| qr:2243 | Heavy smoker | 4 |
Numeric map
| Range from to | Map |
|---|---|
| 0 -9 | 2 |
| 10- 19 | 3 |
| >= 20 | 4 |
Systolic blood pressure
Optional integer
The most recent systolic blood pressure within 5 years prior to the reference date
Rule
Observation
concept in qr:198 Systolic blood pressure
effective date >- -5 years to 0 time relative to reference date
Most recent entry
Handling of values out of range <70 is set to 70, >210 is set to 210
Standard deviation of systolic blood pressures
Optional double
The SAMPLE style Standard deviation of all of the available systolic blood pressures prior to the reference date recorded in the last 5 years
Rule
Observation
concept in qr:198 Systolic blood pressure
effective date >- -5 years to 0 time relative to reference date
Standard deviation (sample)
Townsend score
Optional double
The Townsend score associated with the output area of a patient’s postcode based on the 2001 census data.