This wiki has undergone a migration to Confluence found Here
<meta name="googlebot" content="noindex">

Assessment Scales

From HL7Wiki
Revision as of 14:37, 31 October 2008 by Frankoemig (talk | contribs) (added reference range images)
Jump to navigation Jump to search

There is work underway for a new R-MIM on scores and assessment scales. This page provides the material which will be used for the next ballot cycle. Patient Care has agreed to bring it to ballot as DSTU. So please feel free to support this initiative by providing additional input.

This paper will be organized according to the following three components:

  1. Rationale for paying attention to assessment scales / scores / indexes as a separate topic
  2. The HL7 v3 ballot material persé: use cases, storyboards, dynamic model, static R-MIM model.
  3. Instructions for use to define assessment scale as Detailed Clinical Model, including the coding of it, and use it against the care statement / assessment scale R-MIM.



Principal Contributor: Frank Oemig, Agfa HealthCare & HL7 Germany

Principal Contributor: William Goossen, MD

Principal Contributor: Kevin Coonan, MD

Principal Contributor: Sylvia Thun, MD, DIMDI

Principal Contributor: Rainer Röhrig, MD, University Hospital Giessen


The most fundamental question is always how certain information in HL7 should be transmitted. In most cases, it is information that belongs to the category of "findings" or "observations". Therefore, in HL7 v2.x the OBX-Segment can be used. In HL7 V3 we will find some classes within the RIM and the appropriate domain models. Further it will deal with interpreting the score values and with implementing it in CDA documents and messages.

The so-called Score or assessment systems are findings. Score systems are so-called severity classification systems or point totals systems that pretend to make a quantitative statement on the severity and prognisis of a disease. Typically, scores combines individual values into a total which can be interpreted more easily. In the simplest case, it is just a single value or based on two individual values, in a complex case it can consist of several dozen values which are combined using a complex mathematical calculation.

This document tries to address two kinds of requirements. First, it should define which codes for the most important score and assessment systems must be used. On the other hand, it should explain how the information should be mapped to HL7 v2.x and V3.


There are many score systems in use ([Wikipedia]). Many systems are in use on an international, national or just hospitalwide level. Others are just for scientific purposes.


For our communication the following information are of interest:

  • Code (how to identify the data?)
  • Codesystem (what is the originating catalog?) – LOINC, alternatively Snomed CT, if a licences is available
  • name + description (short textual description)
  • value (information)
  • unit
  • interpretation

In addition to this information for an individual score the underlying values used for calculation are of importance as well. But these are based on the same 6 points mentioned above.

Application Domains

The score systems can be assigned to specific domains. The following table lists the score systems (in alphabetic order) per domain with the assigned code (if available).

Score SystemDescriptionCodeCodesystem

1. Intensive Care and Anasthesia

ABSIAbbreviated burn severity indexn.v.
AISAbbreviated Injury System273254002Snomed CT
APACHEAcute Physiology And Chronic Health Evaluation Score


ASAAmerican Society of Anesthesiologists physical status classification273270000
Snomed CT
CASUSCardiac Surgery Scoretbd
GCSGlasgow Coma Scale
(Beurteilung von Bewusstseinsstörungen bei Erwachsenen)
Snomed CT
HISHannover Intensiv Scoretbd
HTIHospital Trauma Index273525007Snomed CT
ISSInjury Severity Score273533008Snomed CT
KISSKombiniertes Intensiv Scoring Systemn.v.
LODLogistic Organ Dysfunction Score58577001Snomed CT
MODMultiple Organ Dysfunction Score
MPIMannheimer Peritonitis Indextbd
RamsayRamsay sedation scale281400004Snomed CT
RASSRichmond Agitation Sedation Scalen.v.
SAPSSimplified Acute Physiology Score

SAPS: 273811002 Snomed CT
SAPS 2: 273812009 Snomed CT
SAPS 3: n.v.

SOFASepsis-related Organ Failure Assessmentn.v.
TITrauma Index273883005Snomed CT
TISSTherapeutic Intervention Scoring System:
Snomed CT

TSTrauma Score273884004Snomed CT


2. Patient Care

Barthel-Index Barthel Index273302005Snomedt CT ICD-10-GM
Barthel-Index, expandedcognitive function ICD-10-GM
Braden ScaleBraden Scale 38227-5LOINC
Braden Skin Ass. PnlSkin Assessment Pnl38228-3LOINC
BradenQBraden Scale for young children (<5 years)tbdLOINC
FIMFunctional Independence Measure273469003
Snomed CT
FRBFrührehabilitations-Barthel-Index after SchönleU52.-
Snomed CT
NEMSNine equivalents of nursing manpower use scoren.v.
NortonNorton score278898009Snomed CT
WaterlowWaterlow pressure sore risk score278897004Snomed CT


3. Psychiatry and Psychology

AMDPArbeitsgemeinschaft für Methodik und Dokumentation in der Psychiatrien.v.
LFPLübecker Fähigkeitenprofiln.v.
MelbaMerkmalprofile zur beruflichen Eingliederung von Behindertenn.v.
MMSEMini Mental State Examination273617000Snomed CT ICD-10-GM


4. Pediatry

Pediatric GCSPediatric Glasgow Coma Scalen.v.
APGARafter 1 minute

after 5 minutes
after 10 minutes




5. Mobility

Timed “Up & Go


6. Cognition

TFDDTest zur Früherkennung von Demenzen mit Depressionsabgrenzung
Clock Completion


7. Nutrition

MNAMini Nutritional Assessment(after Guigoz


8. Psychology

APSAcute Physiology Score

9. Geriatry

GDSGeriatric Depression Scale273481004
Snomed CT

10. not otherwise classified

Bone density385342005 Snomed CT
BMIBody-Mass-Index measurement
BVBacterial vaginosis scoreB96.
ICD 10
FLACCFace Legs Activity Cry Cinsolability Scoretbd
GleasonGleason Score372278000Snomed CT
HTIHospital Traum Index273525007Snomed CT
IADLIADL (after Lawton and Brody)
LBKLübecker Fähigkeitenprofil
MPMMPM 2 (0)
MPM 2 (24, 48, 72)
Mortality Prediction Model
Snomed CT
Snomed CT
PHQPersonal Health Questionnaire (Depression Score)
PSRPeriodontal Screening and Recording
VASvisuell analog Scalatbd



The code systems are identified by their OIDs which are listed in the following table.

LOINCLogical Observation Identifiers Names and Codes[]2.16.840.1.113883.6.1
ICD 10 GM 2005
ICD-Katalog (German modification 2005)[]
ICD 10 GM 2006
ICD-Katalog (German modification 2006)[]
ICD 10 GM 2007
ICD-Katalog (German modification 2007)[]
ICD 10 GM 2008
ICD-Katalog (German modification 2008)[]
ICD 10 GM 2009
ICD-Katalog (German modification 2009)[]
Snomed CTSNOMED CT is a concept-based, scientifically validated terminology that provides a unique and permanent concept identifier that can be included in multiple HL7 data types including CD and CE. The concepts are managed to avoid "semantic drift" so the meaning remains constant. If the concept is found to be ambiguous or the meaning changes, the concept is inactivated but still retained and the identifier is never reused. SNOMED CT's concepts are interrelated hierarchically and using description logic.[]2.16.840.1.113883.6.96
OPS 2006
OPS 2007
OPS 2008
OPS 2009
Alpha-ID 2008
Alpha-Id 2008[]
Alpha-ID 2009
Alpha-Id 2009[]

Changes from Previous Release

There is currently no previous release. Therefore, this section will be filled next cycle.


Assessment Scales – Scores Structure Overview

Given the interest in earlier versions of the Care Provision Ballot, further work has been undertaken on representing assessment scales, scores or indexes. The scientific testing of such instruments puts specific requirements and constraints on its use in HL7 v3 message structures in order to not only have a semantically equivalent data exchange, but also to keep the clinimetric characteristics of the instruments as a whole. The assessment scales, scoring systems or indexes are observations with specific characteristics. They can consist of severity classification systems or point totals systems that pretend to make a quantitative statement on the severity and prognosis of a disease or other aspect of human functioning. It is quite often an attempt to convert ‘soft’ observations into ‘hard’ data and evidence. Most of such instruments used in healthcare have been tested extensively on validity, reliability and usability. Many of such scoring instruments are used for decades and worldwide. Typically, assessment scales or scores combine the findings of individual values into a total score which can be interpreted more easily against a reference population. In the simplest case, it is just a single value or based on two individual values, in a complex case it can consist of several dozen values which are combined using a complex mathematical calculation or statistical technique.

This R-MIM tries to give guidelines on the representation in information models, in particular against the HL7 clinical statement pattern and the care statement R-MIM for care provision.

In addition to the information model, the appropriate use of terminology and consistency between the information model and the terminology model are crucial for safe exchange of such observations.

Clinical Statement extract

The R-MIM for the assessment scales – scores can be seen as an extract of Clinical and Care Statement Pattern, thus inheriting its characteristics. The R-MIM representation starts on top with the name and identification in the entry-point. For a detailed explanation of all attributes and vocabulary, the reader is referred to generic descriptions of the Reference Information Model, and to the walkthrough of the care statement D-MIM.

Score Observation

The R-MIM then starts with the score observation out of the choice box. As said above, the crucial attributes include:

  • code: used to identify the variable and in which also the code system can be listed.
  • text: attribute to allow the name and description of the assessment instrument
  • value in which the actual score and where applicable the unit can be entered
  • interpretationCode where the interpretation of the value can be explained via codes, often against a reference value.
  • In the derivation code the total score for the assessment scale is recorded. In other words: derivation method is for example to add all values of the separate scores towards the total score.
  • Effective time is the point in time on which the instrument is scored. In order to be valid and reliable, the scoreItems need to have (almost) the same time stamp. Such constraints posed by assessment instruments are important and expand beyond the mere semantic interoperability. For the receiver it is not only important to understand what the message content means, but also be ascertained that the data are collected based on the guidelines for the instrument.
  • In the value of the score, which was created by adding the individual score items, is filled up. This is often a Coded Ordinal data type because it is mandatory to score and fill up all items to get a proper sum score. That is why Mandatory (1..1) component relations often exist for scoring instruments.
  • Of course all relevant attributes can be applied as needed.

Component relationship to ScoreItem Observation

From that point onwards a recursion starts based on the component relationship, allowing either including other score values or observations a score is based upon. Beneath the score Observation is the Observation (OBS) with the name Score item. Both the class Score and the class ScoreItem have class code = OBS.

Derived from relationship to Care Statement CMET

The derived from relation to care statement allows the user to describe any relevant information related to why a score item is scored this way. It allows to express any human thoughts as observations to go alongside with the score itself, or any circumstances as a procedure being carried out, or a specific encounter when it was measured. The relationship is to the choice box, allowing to make such statements on the level of the assessment instrument as a whole, or for an individual scoreItem.

Linkages to subject and provider roles

<to be completed>

Score System Categories

The score systems can be divided into different categories: Those with arbitrary scores, those with discrete values and those with an unspecified number of values. Patient Classification Systems for workload are examples of the first one, the Barthel index is an example of the second category, the BMI (Body Mass Index) and example for the third.

Arbitrary scores

A scale is a set of linear values from a certain range. A reference range can be determined. In this case, an interpretation according to the conventional scheme is possible, i.e. a value is interpreted as "normal" if it is within the area:

However, it should be noted here that an interpretation as too low is not necessarily combined with the abnormal flag.


Discrete values (scores)

The "normal range" and the number of all possible values are identical. Therefore, the standard usage of reference ranges does not work. In principle, the whole range is devided into smaller parts each representing a specific interpretation.

So for example, the (German) Barthel Index allows for the values of 0 to 100 in steps of 5. The reference range, which can be specified, is within the same range, so that the available assessment opportunities (Abnormal flags) are not usable. The interpretation of a score is depending on a part of the reference range to which it belongs. Hence, the referenceRange relationship to another OBS with the name ScoreRange.

For example:

Interpretation shows how the total score should be interpreted. For instance for the Dutch version of the Barthel index, this is 0-9 for seriously limited, 10-19 for moderately limited and 20 for independent. Finally the ScoreChoice box has participations with subject and author as explained in detail in the clinical statement pattern. As mentioned above, an assessment of the results by the conventional scheme of a reference range, where values outside are too high or too low, does not to apply. All values are falling into the range as defined by the score system. This range is - as explained above - to be divided into sections, which then can be evaluated/interpreted separately. Each score system is going to have its own (new) set of interpretation values. Each score system should get its own set of interpretation values which can be defined according to the following scheme. If the code values are coming from different code systems, then they must be included:

Table : Interpretation of results Eventually, some score systems may share the same interpretations.



This D-MIM can be used in different circumstances. Right now, four different use cases are foreseen.

Assessment Scale Define

The D-MIM can be used in definition mood, so that it can convey information about the score system resp. assessment scale itself.

Assessment Scale Order

The primary codes, i.e. the ones on top level and not for the components, can be used to send a request for an observation using scores and assessments.

Assessment Scale Observation

The result of such an observation can be transmitted.

Assessment Scale Query

It should be possible to query for previous results as well.

Application Roles

According to the use case different combinations of application roles are applicable:

  • informer - tracker
  • placer - fulfiller
  • query placer - query fulfiller

Trigger Events

The associated trigger events depend on the use case. This template an be used in messages and/or documents. Therefore, the events will vary.

Refined Message Information Models

HL7 V3 provides the "Clinical Statement Pattern". Here one can find the activity "Observation" with the necessary details. Facilitating this "basic structure", the pattern/template can be reused in other domains as well.

A_ObservationAssessmentScales-Scores (REPC_RM000125UV) REPC RM000125UV-AssessmentScales-ScoresUpdatedQ2VancWedn.jpg

A score or assessment value is an observation. Therefore, as an entry point the observation act has been chosen. If the total score value is to be transferred only, they may use the Observation-Act directly (and exclusively).

But if the total score including all individual observations, the latter has to be assigned to the score as components. This assignement is done recursively so that a component can be a score itself. Within this recursion one can refer to a score or an observation which is used to calculate the total score. Therefore, the act relationship link is done from Score to ScoreChoice.

Both classes can be linked by participations to CMETs for performer, verifier, author etc. or to refer to a reference range.


The walkthrough will be done in the following order:

  • Score
  • Score Item
  • Act-Relationship component
  • Participation author
  • Participation unterzeichzner
  • Participation verifier
  • Participation performer
  • Participation dataEnterer
  • Participation subject
  • Act-Relationship referenceRange
    • Score Range
  • Act-Relationship derivedFrom
    • CMET A_CareStatement

Class Score

This act conveys information about the score itself and acts as a container (grouping) for the details to this score.

classCode := OBS

A score is an observation. Therefore the classCode is set to “OBS”.

moodCode <= ActMoodCompletionTrack

This value can come from ActMoodCompletionTrack and therefore allows to use in different business cycles. Normally, using "EVN" is foreseen. But "RQO" for requests or "DEF" for conveying information about itself is permitted as well.

Here we have to admit, that "DEF" is officially not allowed within clinical statement patterns. This is an action item for the next harmonization meeting.

id (Score-ID) := SET<II> [1..*]

Each Score is identified by a unique id. A value must be provided, esp. if the information is used in different phases of a business cycle.

code (score system) := CD CWE [1..1]

This is the primary value to identify the score system and therefore mandatory. The value may come from different code systems. The possible values can be found in the database.

derivationExpr (calculation method) := ST [0..1]

This optional field can be used to specify how the total score is calculated. In most cases to total score will be the sum of its components. But complex mathematical functions are possible as well. In some cases the calculation is a matter of copyright issues.

direct valueScore only consists of a single value. This vlaue is just interpreted.RASS
sumThe different details are single values which are added into a total.Barthel
Apache II
mathematical calculationThe details are combined according to a mathematical functions.BMI
combinationThe values are combined somehow, e.g. by concatenation.PPR


statusCode (Status) := CS CNE [1..1] <= ActStatus

In most cases the information is transmitted after calculation. Therefore, the statusCode will be "completed".

effectiveTime (observation time) := GTS [0..1]
availabilityTime := TS [0..1]
priorityCode := SET<CE> CWE [0..*] <= ActPriority
confidentialityCode := SET<CE> CWE [0..*] <= Confidentiality
uncertaintyCode := CE CNE [0..1] <= ActUncertainty
languageCode (language) := CE CWE [0..1] <= HumanLanguage
value (total Score Value) := ANY [0..1]

This field contains the value of the total score itself. Normally, it will be an integer or coded ordinal. But other datatypes like strings as for PPR ("A1S2") or real values for BMI are allowed as well.

interpretationCode (Interpretation) := SET<CE> CWE [0..*] <= ObservationInterpretation

This field contains the interpretationof the score value. The code comes from a value set which has been defined for this score system.

methodCode := SET<CE> CWE [0..*] <= ObservationMethod
targetSiteCode := SET<CD> CWE [0..*] <= ActSite

Class ScoreItem

Like the class Score this act conveys information about the component to a score.

classCode := OBS

This act is a placeholder for individual observations. Therefore the classCode is set to “OBS”.

moodCode <= ActMoodCompletionTrack

This value can come from ActMoodCompletionTrack and therefore allows to use in different business cycles. Normally, using "EVN" is foreseen.

id (Score-ID) := SET<II> [0..*]

Each component can be identified by a unique id. A value can be provided, esp. if the information is used in different phases of a business cycle.

code (score system) := CD CWE [1..1] <= ActCode

This is the primary value to identify the component of the score system and is therefore mandatory. The value may come from different code systems. The possible values can be found in the database.

negationInd := BL [0..1]
text := ED [0..1]
statusCode (status) := CS CNE [1..1] <= ActStatus

In most cases the information is transmitted after calculation. Therefore, the statusCode will be "completed".

effectiveTime (observation time) := GTS [0..1]
availabilityTime := TS [0..1]
priorityCode := SET<CE> CWE [0..*] <= ActPriority
confidentialityCode := SET<CE> CWE [0..*] <= Confidentiality
uncertaintyCode := CE CNE [0..1] <= ActUncertainty
languageCode (language) := CE CWE [0..1] <= HumanLanguage
value (score value) := ANY [0..1]

This field contains the value of the score component.

interpretationCode (interpretation of the value) := SET<CE> CWE [0..*] <= ObservationInterpretation

This field contains the interpretation of the score component value. The code comes from a value set which has been defined for this component of the score system.

methodCode := SET<CE> CWE [0..*] <= ObservationMethod
targetSiteCode := SET<CD> CWE [0..*] <= ActSite

Act-Relationship component

This act relationship is used to link a score (as parent) to its components (as children). The use is optional.

typeCode := COMP

Diese Angabe verweist auf die Einzelinformationen, aus denen sich der Score-Wert zusammensetzt.

Participation performer

s. VHitG-Arztbrief

typeCode <= PRF

Participation author

Using this participation the information about the author is included.

author (Angaben zum Author) := [0..*]

Optional können die Score-Werte mit anderen Authorangaben versehen werden.

typeCode <= AUT
functionCode (function of the author) := CE CWE [1..1] <= ParticipationFunction

In der verpflichtenden Funktionsangabe wird angegeben, in welcher Funktion der Author an der Erstellung der Score-Werte mitgewirkt hat.

contextControlCode := CS CNE [0..1] <= ContextControl
noteText := ED [0..1]
time (Zeitpunkt der Dokumentation) := TS [1..1]

Im verpflichtend anzugebenden time Attribut wird der Zeitpunkt der Dokumentation angegeben.

modeCode := CE CWE [0..1]
signatureCode := CE CNE [0..1] <= ParticipationSignature
signatureText := ED [0..1]

Participation Unterzeichner

Ähnlich dem Author können diverse Unterzeichner angefügt werden. Diese Participation ist in obiger Grafik übersichtshalber nicht enthalten.

Participation verifier

s. VHitG-Arztbrief

typeCode <= VRF

Participation dataEnterer

This participation is linked to the R_AssignedPerson CMET.

typeCode <= ENT

Participation subject

Using this participation information about the patient is conveyed. This participation is linked to the R_Patient CMET.

typeCode <= SBJ
contextControlCode := CS CNE [0..1] <= ContextControl
time (Zeitpunkt der Dokumentation) := TS [1..1]
awarenessCode := CE CWE [0..1] <= TargetAwareness

CMET Choice Box

The following CMETs are assigned to the previously listed participations:

  • R_AssignedEntity [universal]
  • R_Patient [universal]
  • R_RelatedParty [universal]
  • R_AssignedPerson [universal]

Act-Relationship referenceRange

Über diese (optionale) Beziehung wird der Referenzbereich für den Score-Wert festgelegt. Das ist der Bereich der Werte, in dem die meisten (aber nicht alle) Gesunden liegen sollten.

Mitunter gelten die Bereichsfestlegungen über Normalwerte nicht, da die gemessenen/errechneten Werte alle innerhalb des Normbereiches liegen, jedoch unterschiedlich interpretiert werden müssen. In diesem Fall findet die „Precondition“ Anwendung.

typeCode := REFV

Diese Angabe deklariert die Beziehung als Bereichsfestlegung.

contextControlCode := CS CNE [0..1] <= ContextControl
contextConductionInd := BL [1..1] = "false"
seperatableInd := BL [0..1]

Diese Information gibt an, ob die Quell-Klasse (Score-Wert) auch ohne den Referenzbereich genutzt werden darf oder nicht.

class ScoreRange

In dieser Klasse werden die Normbereiche – evtl. mit Vorbedingungen – übermittelt.

classCode := OBS

Da es sich hier ebenfalls um eine Beobachtung handelt ist der classCode natürlich “OBS”.

moodCode := EVN.CRT

Die Einzelwerte als Grundlage des Score-Wertes sind ermittelt worden, d.h. sie liegen vor und werden deshalb im Event-Mood übermittelt.

negationInd := Verneinung BL [1..1] <= false

Die Normbereiche werden nicht verneint.

text := ED [0..1]

value (Bereichswert) := ANY CWE [1..1] =

In diesem Feld wird der Normwertbereich angegeben. Typischerweise wird er als Intervall kommuniziert. Es ist aber auch denkbar, dass hier eine Wertemenge angegeben wird, so dass der Datentyp SET<T> zum Einsatz kommt.

interpretationCode := CE CWE [1..1] <= ObservationInterpretation

Act-Relationship derivedFrom

This act relationhip links the information for the score system and its components to "real" care information. Sometimes objective inormation which has been stated earlier can be reused within a score or at least to calculate the informatione needed within the score components from measured values. This generic relationship allows for inclusion of arbitrary information as needed.

typeCode := DRIV

The score (item) information is derived from care information.

CMET A_CareStatement

Hierarchical Message Descriptions


Dynamic Model

This information model represents a generic template which can be used in messages and documents as well.

Open Issues

Description Parent: Care Structures Event Statement (REPC_RM000100UV)