QRISK3

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 QRISK3 and the free to use Web site can be viewed https://qrisk.org

Integration with systems

Systems may have access to longitudinal health records, in particular those held in General Practice. In that case those systems may elect to use QRISK in a way that provides likely values for the variables used in the algorithm, those values being derived from the records.

That being the 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. 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 on or before the reference date

Variables and function parameters

QRISK® operates as a function whose parameters represent independent variables. 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 as arguments (e.g. as case statement)

If variables are unknown (missing) or their values are out of range, the algorithm may either reject the request, provide a default value, or adjust the out of range value to an outer limit.

Each concept set has an IRI and the iri namespace is http://apiqcodes.org/qcodes#. Which uses the iri prefix qr in the following table

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.

sbp

Integer (nullable)

The most recent systolic blood pressure prior to search date recorded in the last 5 years

198

n/a

sbps5

Double (nullable)

Standard deviation of all of the available systolic blood pressures prior to the search date recorded in the last 5 years

198

n/a

town

Double (nullable)

The Townsend score associated with the output area of a patient’s postcode based on the 2001 census data.

n/a

n/a

postcode

String

Patient’s postcode. This can be missing if Townsend score is supplied.

n/a

n/