# Associated symptoms...
**URL:** https://discourse.openehr.org/t/associated-symptoms/14778
**Category:** Clinical (archive)
**Created:** [30 June 2008 13:49 UTC](https://discourse.openehr.org/t/associated-symptoms/14778 "2008-06-30T13:49:28Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@Bruno\_Cadonna](https://discourse.openehr.org/u/Bruno_Cadonna)
#### Post date: [30 June 2008 13:49 UTC](https://discourse.openehr.org/t/associated-symptoms/14778/1 "2008-06-30T13:49:28Z")
Hi all,
In the archetype openEHR-EHR-CLUSTER.symptom.v3.adl there is a CLUSTER archetype node with id at0020 with label "Associated symptoms and events".
Can a symptom A have an associated symptom B with onset date before the onset date of the symptom A or with a duration exceeding the duration of symptom A?
Example:
A patient was diagnosed influenza and suffers from time point 1 to time point 3 from chills, from time point 2 to time point 5 from fever and from time point 4 to time point 6 from coughing.
Can chills and coughing be associated symptoms of fever?
Or have associated symptoms totally other semantics?
Cheers
Bruno
---
### Author:  [@system](https://discourse.openehr.org/u/system)
#### Post date: [2 July 2008 11:14 UTC](https://discourse.openehr.org/t/associated-symptoms/14778/2 "2008-07-02T11:14:44Z")
Hi Bruno
The openEHR architecture does not allow embedded time series for observations. To have the timing of symptoms you need an event and all data related to that event (which may be a period) has a separate timing.
The idea in this archetype I believe is to allow some simple associations to be explicit and to simplify the data entry requirements while allowing coding if required.
So, to answer your question directly - if you want to enter the timing of any symptom in a computable form, it needs to be at the root of the observation. Thus associated symptoms cannot have different times that are computable.
Cheers, Sam
Bruno Cadonna wrote:
> **(attachments)**
>
> 
---
### Author:  [@Bruno\_Cadonna](https://discourse.openehr.org/u/Bruno_Cadonna)
#### Post date: [2 July 2008 11:50 UTC](https://discourse.openehr.org/t/associated-symptoms/14778/3 "2008-07-02T11:50:51Z")
Hi Sam,
Thank you for your reply!
\> So, to answer your question directly - if you want to enter the timing
\> of any symptom in a computable form, it needs to be at the root of the
\> observation. Thus associated symptoms cannot have different times that
\> are computable.
Does this mean all times not at the root of an OBSERVATION should not be used for computations?
If yes, is this valid also for all times in ITEM\_STRUCTUREs?
What about EVALUATIONs like diagnoses which have times only in ITEM\_STRUCTUREs?
Cheers
Bruno
Sam Heard wrote:
---
### Author:  [@system](https://discourse.openehr.org/u/system)
#### Post date: [8 July 2008 11:13 UTC](https://discourse.openehr.org/t/associated-symptoms/14778/4 "2008-07-08T11:13:54Z")
Hi Bruno
The OBSERVATION class has a timing model that makes the timing explicit
and adds handling of intervals and other concepts. For the timing of
something in an observation (the clinically relevant time in HL7 v3) you
need to look at the event time.
All times are valid when explicitly expressed in evaluations.
I hope this is clear
Bruno Cadonna wrote:
---
### Author:  [@Bruno\_Cadonna](https://discourse.openehr.org/u/Bruno_Cadonna)
#### Post date: [9 July 2008 15:09 UTC](https://discourse.openehr.org/t/associated-symptoms/14778/5 "2008-07-09T15:09:25Z")
Hi all,
After a thread on the openehr-clinical list about associated symptoms (cf. subject "Associated symptoms" on openehr-clinical) some technical questions about computation of time came to my mind.
In openEHR the time data can be found in different places in different ENTRY types.
OBSERVATIONs have HISTORYs for attributes "data" and "state". Time data in HISTORY represent the timing of observations, they may be used for computations. Time data in the ITEM\_STRUCTURE of the attribute "data" of an EVENT in a HISTORY should not be used for computation.
An example for the latter is archetype openEHR-EHR-OBSERVATION.symptom\_check.v1 which includes CLUSTER archetype openEHR-EHR-CLUSTER.symptom.v3.adl. openEHR-EHR-CLUSTER.symptom.v3.adl defines time data at archetype node at0063 "Date / time of onset". This time data should not be used for computation to avoid contradiction with time data recorded in the HISTORY of the OBSERVATION.
Is this right?
EVALUATIONs have time data somewhere in the ITEM\_STRUCTURE of their attribute "data". This time data may be used for computation.
For example archetype openEHR-EHR-EVALUATION.problem-diagnosis.v1 defines time data at archetype node at0003 "Date of initial onset" which may be used for computation.
Is this right?
ACTIONs have time data in attribute "time" which states when the action completed and in the ITEM\_STRUCTURE of the attribute "description". Both time data may be used for computation.
An example for the latter is archetype openEHR-EHR-ACTION.medication.v1 which includes archetype openEHR-EHR-ITEM\_TREE.medication.v1. openEHR-EHR-ITEM\_TREE.medication.v1 defines time data at archetype node at0019 "Date (time) of first administration". This time data may be used for computation.
Is this right?
What about archetype node at0032 "Date (time) of last administration" of openEHR-EHR-ITEM\_TREE.medication.v1? Does it contradict time data in attribute "time" in ACTIONs?
INSTRUCTIONs have time data in "expiry\_time" and in the ITEM\_STRUCTURE of the attribute "description". Both time data may be used for computation.
An example for the latter is archetype openEHR-EHR-INSTRUCTION.medication.v1 which includes archetype openEHR-EHR-ITEM\_TREE.medication.v1. openEHR-EHR-ITEM\_TREE.medication.v1 defines time data at archetype node at0019 "Date (time) of first administration". This time data may be used for computation.
Is this right?
Here archetype node at0032 "Date (time) of last administration" of openEHR-EHR-ITEM\_TREE.medication.v1 could also contradict the attribute "expiry\_time" of INSTRUCTIONs, but the semantics of these time data is quite different, thus this should not be a problem, right?
Any comments really welcome.
Cheers,
Bruno
---
### Author:  [@thomas.beale](https://discourse.openehr.org/u/thomas.beale)
#### Post date: [9 July 2008 17:03 UTC](https://discourse.openehr.org/t/associated-symptoms/14778/6 "2008-07-09T17:03:24Z")
Bruno Cadonna wrote:
> Hi all,
>
> After a thread on the openehr-clinical list about associated symptoms
> (cf. subject "Associated symptoms" on openehr-clinical) some technical
> questions about computation of time came to my mind.
>
> In openEHR the time data can be found in different places in different
> ENTRY types.
>
> OBSERVATIONs have HISTORYs for attributes "data" and "state". Time
> data in HISTORY represent the timing of observations, they may be used
> for computations. Time data in the ITEM\_STRUCTURE of the attribute
> "data" of an EVENT in a HISTORY should not be used for computation.
> An example for the latter is archetype
> openEHR-EHR-OBSERVATION.symptom\_check.v1 which includes CLUSTER
> archetype openEHR-EHR-CLUSTER.symptom.v3.adl.
> openEHR-EHR-CLUSTER.symptom.v3.adl defines time data at archetype node
> at0063 "Date / time of onset". This time data should not be used for
> computation to avoid contradiction with time data recorded in the
> HISTORY of the OBSERVATION.
>
> Is this right?
Any timing information that is correct in the EHR should be usable for
computation - there is no reason not to. BTW times like 'date/time of
onset' will usually occur in Evaluation archetypes, not Observation
archetypes.
> EVALUATIONs have time data somewhere in the ITEM\_STRUCTURE of their
> attribute "data". This time data may be used for computation.
> For example archetype openEHR-EHR-EVALUATION.problem-diagnosis.v1
> defines time data at archetype node at0003 "Date of initial onset"
> which may be used for computation.
>
> Is this right?
same meaning as above.
> ACTIONs have time data in attribute "time" which states when the
> action completed and in the ITEM\_STRUCTURE of the attribute
> "description". Both time data may be used for computation.
> An example for the latter is archetype
> openEHR-EHR-ACTION.medication.v1 which includes archetype
> openEHR-EHR-ITEM\_TREE.medication.v1.
> openEHR-EHR-ITEM\_TREE.medication.v1 defines time data at archetype
> node at0019 "Date (time) of first administration". This time data may
> be used for computation.
>
> Is this right?
> What about archetype node at0032 "Date (time) of last administration"
> of openEHR-EHR-ITEM\_TREE.medication.v1? Does it contradict time data
> in attribute "time" in ACTIONs?
I assume that this wouldbe more properly named 'date/time of previous
administation' - I assume it is there to provide an idea of the period
between administrations - useful e.g. in the case of painkiller medication.