Pathology requirements TIMED MEASUREMENTS
Thomas I am not sure that we need to do such a major rework. These samples are time ordered but have no sensible time. So they could appear in the history list without an offset, labelled in what ever way was helpful, recognising they are part of the same measurement. On thinking about this (if you wanted to keep all the measurements) a simple office based measurement like peak flow is a candidate - you might do three measurements in a row. At the moment the history demands an offset - the set of measurements would still be timed - but only the sequence of each would be known, not the time of each individual. This seems more appropriate. The query could return them all at the same time or, as I have suggested, with a nominal offset 1,2,3 etc This would allow for the fuzziness of a series to be captured. Another alternative is just to allow the application to put in what ever time it likes as the offset, and label them Sample 1, Sample 2. This would require no changes, and would not upset the query model. I probably favour this approach as there is no doubt there is a time element to sampling, otherwise it is not a sequence. Cheers, Sam -Original Message- From: Thomas Beale [mailto:thomas at deepthought.com.au] Sent: Friday, 24 October 2003 5:58 PM To: Sam Heard; Openehr-Technical Subject: Re: Pathology requirements TIMED MEASUREMENTS 1. We recognise this is a sampling issue and there should be a label on each sample which is transfered to the report - we have sample 1, 2 and 3 with three separate microscopies and cultures in a single composition. This would get around the confusion of trying to deal with this as a timing issue - it would work for any sampling including location. We do not want to compare these CSF samples in queries as equals but we would have some sort of label associated. So, the sample label and order might be part of this - in the request and then in the result. I guess this goes on at the moment. 2. We have a sequence idea in the event model, by using the offset but having 'sequence' as the unit rather than time. This would mean that people did not have to enter spurious times in the data and name the event as Sample 1, which could be misleading. I guess there are a few possibiities. a) we change HISTORY to SEQUENCE and make it general enough to cope with other sequences, not just time b) we add a type SEQUENCE and make the current HISTORY a subtype of it. The only reason to do this, rather than to have two disjoint types would be to enable software re-use (less code; better code) and to allow runtime substitutability. I am not sure what query could sensibly request all sequences, including histories, so I am not sure if this is an argument c) we add a type SEQUENCE as another subtype of STRUCTURE. Without having done the analysis, I would favour b), since there appears to be a fair overlap of semantics and therefore argument for reuse. What we need is a nice statement of a new model for history, which includes means, maxima, minima etc as Sam has been modelling, and a similar model for sequence. Then we can see what to do about changing the Data Structures Information Model - thomas - thomas c) - If you have any questions about using this list, please send a message to d.lloyd at openehr.org
Pathology requirements TIMED MEASUREMENTS
Sam wrote: Thomas I am not sure that we need to do such a major rework. These samples are time ordered but have no sensible time. So they could appear in the history list without an offset, labelled in what ever way was helpful, recognising they are part of the same measurement. On thinking about this (if you wanted to keep all the measurements) a simple office based measurement like peak flow is a candidate - you might do three measurements in a row. At the moment the history demands an offset - the set of measurements would still be timed - but only the sequence of each would be known, not the time of each individual. This seems more appropriate. But I think the whole idea of History is about time. Having a sequence type would not be much work. The abstraction seems quite simple, but we need to do more analysis... The query could return them all at the same time or, as I have suggested, with a nominal offset 1,2,3 etc This would allow for the fuzziness of a series to be captured. Another alternative is just to allow the application to put in what ever time it likes as the offset, and label them Sample 1, Sample 2. This would require no changes, and would not upset the query model. I probably favour this approach as there is no doubt there is a time element to sampling, otherwise it is not a sequence. but maybe even though sequential samples were done at different times, time is not the variable of the sequence - it could be position (in a limb being scanned for example) or separate tissue samples as you mention below. Then the fact that the results were generated (slightly?) separated in time is irrelevant - in fact the proper ordering of the series might be different from the time-ordering of the result generation...also, imaging equipment might generate sequences of results in a spatial dimension at the same moment. I think we have to analyse this further Any other sequence examples anyone? - thomas - If you have any questions about using this list, please send a message to d.lloyd at openehr.org
Pathology requirements TIMED MEASUREMENTS
Bhupinder The only values we are not wanting to show are those that are wrong - and have been changed in a later version. The idea behind this is to store the information in an openEHR system inside the Pathology service and then send an extract - rather than develop a lot of messages. Cheers, Sam -Original Message- From: owner-openehr-technical at openehr.org [mailto:owner-openehr-technical at openehr.org]On Behalf Of Bhupinder Singh Sent: Sunday, 26 October 2003 11:50 PM To: Thomas Beale; Openehr-Technical Subject: Re: Pathology requirements TIMED MEASUREMENTS What you say is one possibility. What is important is when there are two results out of the scenario and the readings are different. Would it be correct to take a mean. The difference in the reading may be on account of a number of causes starting from --Machine error --Human Error etc. The question is that there is a difference and this needs to be gone into in fact this requires to be highlighted and not covered through a mean value generated. Graphical representation should show both values and leave it to the clinician to decide what action he prefers to take. Textual display should show both values too. Bhupinder - Original Message - From: Thomas Beale thomas at deepthought.com.au To: Openehr-Technical openehr-technical at openehr.org Sent: Friday, October 24, 2003 4:29 AM Subject: Re: Pathology requirements TIMED MEASUREMENTS Bhupinder Singh bobdog at sancharnet.in wrote: Dear Sam, What you say is correct. In clinical practice it is also possible that the same sample is sent to two labs for the same test and the protocol followed by both the labs is same so is the est method and the unit of reporting. The sample date and time is the same. These two results have to be viewed and stored. Thus there should be a method to store and retrieve values where the date and time of sample and the test type and method and the UOM is the same needs to be available. Eg Blood Sugar reporting unit and test method are the same so is the date and time of the sample. Bhupinder this is an inteersting scenario actually, since even if there are two perfectly legitimate test results (let's say submitted to the EHR a day after each other) they don't really represent distinct results - they are the same result (presumably) submitted at same or different times. Wen doing statistical or other queries we have to be careful - if we draw the values on a graph for example of bsl over last five days, there might be two values at the one timepoint (where the timepoints are the times of taking samples, not doing the test - i.e. the biologically significant point in time). One way to look at thist situation is to say that all test results where there is just a single result are just a special case of a statistical testing situation in which at any point in body time, a sample might be tested any number of times (and more than one sample might be made as well) - giving a constellation of results. Where there are multiple results for the one biological timepoint, we could consider it as a statistical strengthening of the confidence in the result. Probably what applications processing the results should do is consider N results at the same biological timepoint to be the same as one, whoe value is the mean of the N, and whose confidence is some higher value than that attributed to single value samples. - thomas beale - If you have any questions about using this list, please send a message to d.lloyd at openehr.org - If you have any questions about using this list, please send a message to d.lloyd at openehr.org - If you have any questions about using this list, please send a message to d.lloyd at openehr.org
Pathology requirements TIMED MEASUREMENTS
HI, On one hand there is the notion as used in HL7 where series of messages update databases producing a list of updated measurements. On the other hand there is the notion as used in CEN/TC251 and OpenEHR where documents are used to enhance the raw data by providing a human interpretation and advice by an expert using the updated measurements in the database. Gerard -- Gerard Freriks, MD Convenor CEN/TC251 WG1 TNO-PG Zernikedreef 9 Leiden The Netherlands +31 71 5181388 +31 654 792800 -- private -- Gerard Freriks, arts Huigsloterdijk 378 2158 LR Buitenkaag The Netherlands +31 252 544896 +31 654 792800 From: Sam Heard sam.heard at bigpond.com Reply-To: Sam Heard sam.heard at bigpond.com Date: Mon, 27 Oct 2003 11:41:47 +0930 To: Bhupinder Singh bobdog at sancharnet.in, Thomas Beale thomas at deepthought.com.au, Openehr-Technical openehr-technical at openehr.org Subject: RE: Pathology requirements TIMED MEASUREMENTS Bhupinder The only values we are not wanting to show are those that are wrong - and have been changed in a later version. The idea behind this is to store the information in an openEHR system inside the Pathology service and then send an extract - rather than develop a lot of messages. Cheers, Sam - If you have any questions about using this list, please send a message to d.lloyd at openehr.org
Pathology requirements TIMED MEASUREMENTS
Bhupinder Singh bobdog at sancharnet.in Hi Sam, What yo usuggest is OK . But the issue is who is to decide what is right and what is wrong. Should it not be the prerogative of the clinician. There are situations where medical decisions are based upon results which trigger clinical decisions. How would you hide a wrong result once it has been acted upon by the clinician. Example a report of Serum Potassium of say 6.0 has been sent to the clinician. This is a medical emergency and the clinician has to act upon it to reduce the high level. His action is based upon the result. If he does not act it will be an act of medical negligence. The lab thereafter does a correction and replaces the result of the test say Potassium of 4.0. In the scenario suggested by you this would mean that the result will be filtered out and not be available to the clinician. what he means here is that in normal processing, using the latest historical state of the record, the 6.0 will no longe be picked up in queries, the 4.0 will. But the versions are still there, and in the case of a medico-legal investigation, a snapshot of the EHR exactly as it was at the time of the clinician's decision can be generated (just like getting a prior version of Linux kernel from a CVS server) and it can be shown what evidence the clinician's actions were based on. So the version control system does two things: it enables the current cut of the record to reflect the curent information about the patient, plans etc, and it allows any prior decision to be investigated medico-legally by going backwards in time and reconstructing the record as it was at that moment - i.e. it enables one to know what the EHR looked like at any prior moment in time. So whatever the outcome (even adverse) the clinician can be shown to have acted reasonably, given the information at his/her disposal. The question that will arise is the support for the action taken by the clinicians would in the absence of the report be an act of negligence. In reality the result has been withdrawn. This would raise the possibility of a malpractice suit. Alternatively the patient has an adverse event because of the action of the doctor and the support team views the results and find that there is no Result to support the clinicians action the clinicians action giving rise to another conflict situation. As I say, this can't happen - that's what the whole version control/chnage management system is all about. All reports which have been released shall not be available for being withdrawn and replaced for legal and professional standpoint a report can be appended to and not cancelled. The audit trail is necessary and a mandatory keeping in mind the laws that are coming into place to deal with electronic transaction. correct - all this is still available - nothing in the EHR is ever deleted. What is visible at a moment in time depends on the semantics of versioning. It's just like a bug in software - go back through the CVS server and you can find the version with the bug (in case someone wants to prove that the software used to act differently), but today, in teh current snapshot, the bug is gone, since we don't want it operationally affecting us now. - thomas beale - If you have any questions about using this list, please send a message to d.lloyd at openehr.org
Pathology requirements TIMED MEASUREMENTS
One should take care never to obscure the reality of the fact that you have two separate test results. That reality needs to be captured somewhere, at some level of the EHR. The algorithm that the clinician or researcher applies to these two results would be another matter. -C At 06:20 AM 10/26/2003 -0800, Bhupinder Singh wrote: What you say is one possibility. What is important is when there are two results out of the scenario and the readings are different. Would it be correct to take a mean. The difference in the reading may be on account of a number of causes starting from --Machine error --Human Error etc. The question is that there is a difference and this needs to be gone into in fact this requires to be highlighted and not covered through a mean value generated. Graphical representation should show both values and leave it to the clinician to decide what action he prefers to take. Textual display should show both values too. Bhupinder - Original Message - From: Thomas Beale thomas at deepthought.com.au To: Openehr-Technical openehr-technical at openehr.org Sent: Friday, October 24, 2003 4:29 AM Subject: Re: Pathology requirements TIMED MEASUREMENTS Bhupinder Singh bobdog at sancharnet.in wrote: Dear Sam, What you say is correct. In clinical practice it is also possible that the same sample is sent to two labs for the same test and the protocol followed by both the labs is same so is the est method and the unit of reporting. The sample date and time is the same. These two results have to be viewed and stored. Thus there should be a method to store and retrieve values where the date and time of sample and the test type and method and the UOM is the same needs to be available. Eg Blood Sugar reporting unit and test method are the same so is the date and time of the sample. Bhupinder this is an inteersting scenario actually, since even if there are two perfectly legitimate test results (let's say submitted to the EHR a day after each other) they don't really represent distinct results - they are the same result (presumably) submitted at same or different times. Wen doing statistical or other queries we have to be careful - if we draw the values on a graph for example of bsl over last five days, there might be two values at the one timepoint (where the timepoints are the times of taking samples, not doing the test - i.e. the biologically significant point in time). One way to look at thist situation is to say that all test results where there is just a single result are just a special case of a statistical testing situation in which at any point in body time, a sample might be tested any number of times (and more than one sample might be made as well) - giving a constellation of results. Where there are multiple results for the one biological timepoint, we could consider it as a statistical strengthening of the confidence in the result. Probably what applications processing the results should do is consider N results at the same biological timepoint to be the same as one, whoe value is the mean of the N, and whose confidence is some higher value than that attributed to single value samples. - thomas beale - If you have any questions about using this list, please send a message to d.lloyd at openehr.org - If you have any questions about using this list, please send a message to d.lloyd at openehr.org Christopher J. Feahr, O.D. Optiserv Consulting (Vision Industry) http://Optiserv.com http://VisionDataStandard.org Office (707) 579-4984 Cell(707) 529-2268 - If you have any questions about using this list, please send a message to d.lloyd at openehr.org
Pathology requirements TIMED MEASUREMENTS
Hi Sam, What yo usuggest is OK . But the issue is who is to decide what is right and what is wrong. Should it not be the prerogative of the clinician. There are situations where medical decisions are based upon results which trigger clinical decisions. How would you hide a wrong result once it has been acted upon by the clinician. Example a report of Serum Potassium of say 6.0 has been sent to the clinician. This is a medical emergency and the clinician has to act upon it to reduce the high level. His action is based upon the result. If he does not act it will be an act of medical negligence. The lab thereafter does a correction and replaces the result of the test say Potassium of 4.0. In the scenario suggested by you this would mean that the result will be filtered out and not be available to the clinician. The question that will arise is the support for the action taken by the clinicians would in the absence of the report be an act of negligence. In reality the result has been withdrawn. This would raise the possibility of a malpractice suit. Alternatively the patient has an adverse event because of the action of the doctor and the support team views the results and find that there is no Result to support the clinicians action the clinicians action giving rise to another conflict situation. All reports which have been released shall not be available for being withdrawn and replaced for legal and professional standpoint a report can be appended to and not cancelled. The audit trail is necessary and a mandatory keeping in mind the laws that are coming into place to deal with electronic transaction. For any successful system once the report has been released there is to be no way that result can be withdrawn by the releasing department in this case the pathology department so that it is no longer visible. It is essential that ability to modify / alter/ change shall be through an audit trail and the old and new values are to be available within the pathology module. The ability to modify should how ever be restricted to the pathology department till the time the report has not been released. Once released they(pathology Dept) will also have no rite to cancel it in anti time. This report can then be acted upon through a way that could be that the value is to be blocked would be through a date and time stamp and marking the result with a flag that says for example to be ignored. This will cover the clinician in case any action has been taken by him and the lab has corrected itself and maintain the sanctity of the record being generated. RGDS Bhupinder - Original Message - From: Sam Heard sam.he...@bigpond.com To: Bhupinder Singh bobdog at sancharnet.in; Thomas Beale thomas at deepthought.com.au; Openehr-Technical openehr-technical at openehr.org Sent: Sunday, October 26, 2003 6:11 PM Subject: RE: Pathology requirements TIMED MEASUREMENTS Bhupinder The only values we are not wanting to show are those that are wrong - and have been changed in a later version. The idea behind this is to store the information in an openEHR system inside the Pathology service and then send an extract - rather than develop a lot of messages. Cheers, Sam -Original Message- From: owner-openehr-technical at openehr.org [mailto:owner-openehr-technical at openehr.org]On Behalf Of Bhupinder Singh Sent: Sunday, 26 October 2003 11:50 PM To: Thomas Beale; Openehr-Technical Subject: Re: Pathology requirements TIMED MEASUREMENTS What you say is one possibility. What is important is when there are two results out of the scenario and the readings are different. Would it be correct to take a mean. The difference in the reading may be on account of a number of causes starting from --Machine error --Human Error etc. The question is that there is a difference and this needs to be gone into in fact this requires to be highlighted and not covered through a mean value generated. Graphical representation should show both values and leave it to the clinician to decide what action he prefers to take. Textual display should show both values too. Bhupinder - Original Message - From: Thomas Beale thomas at deepthought.com.au To: Openehr-Technical openehr-technical at openehr.org Sent: Friday, October 24, 2003 4:29 AM Subject: Re: Pathology requirements TIMED MEASUREMENTS Bhupinder Singh bobdog at sancharnet.in wrote: Dear Sam, What you say is correct. In clinical practice it is also possible that the same sample is sent to two labs for the same test and the protocol followed by both the labs is same so is the est method and the unit of reporting. The sample date and time is the same. These two results have to be viewed and stored. Thus there should be a method to store and retrieve values where the date and time of sample and the test type and method and the UOM is the same needs
Pathology requirements TIMED MEASUREMENTS
Bhupinder The protocol describes the methods of measurement - each measure can only have one protocol - so this means that the measurement would be entered twice - quite appropriate because it is unlikely that a different method will lead to exactly the same result. Cheers, Sam -Original Message- From: owner-openehr-technical at openehr.org [mailto:owner-openehr-technical at openehr.org]On Behalf Of Bhupinder Singh Sent: Thursday, 23 October 2003 1:12 PM To: Sam Heard; Openehr-Technical Subject: Re: Pathology requirements TIMED MEASUREMENTS Further to what you have stated there will also be events such as sample is single time is same and the test is same but method of reporting and or conducting test is different. Blood Sugar is one example sample is taken and tested on the bedside and sent to a lab also. These events and results need to be accommodated. Bhupinder - Original Message - From: Sam Heard sam.heard at bigpond.com To: Openehr-Technical openehr-technical at openehr.org Sent: Wednesday, October 22, 2003 4:02 PM Subject: Pathology requirements TIMED MEASUREMENTS TIMED MEASUREMENTS The timed nature of specimens is dealt with in the history and event model of the RM and available in the archetype editor. This deals with timed measurements and interval measurements. The idea of a 21 day progesterone is covered in state information relating to the time since the last menstrual period - BUT there is still the idea of an untimed sequence of events where the order is critical. There are also sequenced events when it comes to looking for stool microscopy, occult blood - but these are reported separately and really are administrative rather than of the nature I will describe here. The best examples of this seem to occur in sampling - three samples of CSF - the first, second and third - or shavings for histology looking for depth of tumour. There are more, such as respiratory function tests with particular challenges - and timing is not an issue. These occur one after the other but the sequence is the only thing that is important - not the time - and time would probably be made up. The question is, how do we deal with this. I think we have two choices: 1. We recognise this is a sampling issue and there should be a label on each sample which is transfered to the report - we have sample 1, 2 and 3 with three separate microscopies and cultures in a single composition. This would get around the confusion of trying to deal with this as a timing issue - it would work for any sampling including location. We do not want to compare these CSF samples in queries as equals but we would have some sort of label associated. So, the sample label and order might be part of this - in the request and then in the result. I guess this goes on at the moment. 2. We have a sequence idea in the event model, by using the offset but having 'sequence' as the unit rather than time. This would mean that people did not have to enter spurious times in the data and name the event as Sample 1, which could be misleading. Comments? Cheers, Sam Dr Sam Heard Ocean Informatics, openEHR Co-Chair, EHR-SIG, HL7 Chair EHR IT-14-9-2, Standards Australia Hon. Senior Research Fellow, UCL, London 105 Rapid Creek Rd Rapid Creek NT 0810 Ph: +61 417 838 808 sam.heard at bigpond.com www.openEHR.org www.HL7.org __ - If you have any questions about using this list, please send a message to d.lloyd at openehr.org - If you have any questions about using this list, please send a message to d.lloyd at openehr.org - If you have any questions about using this list, please send a message to d.lloyd at openehr.org
Pathology requirements TIMED MEASUREMENTS
Bhupinder Singh said: Further to what you have stated there will also be events such as sample is single time is same and the test is same but method of reporting and or conducting test is different. Blood Sugar is one example sample is taken and tested on the bedside and sent to a lab also. These events and results need to be accommodated. If I understand correctly, we are talking about the same sample, but being tested twice? These are separate tests, and could take place a quite different times (e.g. hours apart); they are done by different methods, and probably different providers/people. They will become available in the EHR at different times, so the only thing in common really is the source of the sample - and this should be reported in the test data. - thomas beale - If you have any questions about using this list, please send a message to d.lloyd at openehr.org
Pathology requirements TIMED MEASUREMENTS
Bhupinder Singh bobdog at sancharnet.in wrote: Dear Sam, What you say is correct. In clinical practice it is also possible that the same sample is sent to two labs for the same test and the protocol followed by both the labs is same so is the est method and the unit of reporting. The sample date and time is the same. These two results have to be viewed and stored. Thus there should be a method to store and retrieve values where the date and time of sample and the test type and method and the UOM is the same needs to be available. Eg Blood Sugar reporting unit and test method are the same so is the date and time of the sample. Bhupinder this is an inteersting scenario actually, since even if there are two perfectly legitimate test results (let's say submitted to the EHR a day after each other) they don't really represent distinct results - they are the same result (presumably) submitted at same or different times. Wen doing statistical or other queries we have to be careful - if we draw the values on a graph for example of bsl over last five days, there might be two values at the one timepoint (where the timepoints are the times of taking samples, not doing the test - i.e. the biologically significant point in time). One way to look at thist situation is to say that all test results where there is just a single result are just a special case of a statistical testing situation in which at any point in body time, a sample might be tested any number of times (and more than one sample might be made as well) - giving a constellation of results. Where there are multiple results for the one biological timepoint, we could consider it as a statistical strengthening of the confidence in the result. Probably what applications processing the results should do is consider N results at the same biological timepoint to be the same as one, whoe value is the mean of the N, and whose confidence is some higher value than that attributed to single value samples. - thomas beale - If you have any questions about using this list, please send a message to d.lloyd at openehr.org
Pathology requirements TIMED MEASUREMENTS
TIMED MEASUREMENTS The timed nature of specimens is dealt with in the history and event model of the RM and available in the archetype editor. This deals with timed measurements and interval measurements. The idea of a 21 day progesterone is covered in state information relating to the time since the last menstrual period - BUT there is still the idea of an untimed sequence of events where the order is critical. There are also sequenced events when it comes to looking for stool microscopy, occult blood - but these are reported separately and really are administrative rather than of the nature I will describe here. The best examples of this seem to occur in sampling - three samples of CSF - the first, second and third - or shavings for histology looking for depth of tumour. There are more, such as respiratory function tests with particular challenges - and timing is not an issue. These occur one after the other but the sequence is the only thing that is important - not the time - and time would probably be made up. The question is, how do we deal with this. I think we have two choices: 1. We recognise this is a sampling issue and there should be a label on each sample which is transfered to the report - we have sample 1, 2 and 3 with three separate microscopies and cultures in a single composition. This would get around the confusion of trying to deal with this as a timing issue - it would work for any sampling including location. We do not want to compare these CSF samples in queries as equals but we would have some sort of label associated. So, the sample label and order might be part of this - in the request and then in the result. I guess this goes on at the moment. 2. We have a sequence idea in the event model, by using the offset but having 'sequence' as the unit rather than time. This would mean that people did not have to enter spurious times in the data and name the event as Sample 1, which could be misleading. Comments? Cheers, Sam Dr Sam Heard Ocean Informatics, openEHR Co-Chair, EHR-SIG, HL7 Chair EHR IT-14-9-2, Standards Australia Hon. Senior Research Fellow, UCL, London 105 Rapid Creek Rd Rapid Creek NT 0810 Ph: +61 417 838 808 sam.heard at bigpond.com www.openEHR.org www.HL7.org __ - If you have any questions about using this list, please send a message to d.lloyd at openehr.org
Pathology requirements TIMED MEASUREMENTS
Sam, I agree. But there will be the situation when the method is the same and the sample date and time is the same( this I am suggesting as this is a common practice in clinical practice to have and ask for two reports where the method is the same and the sample is drawn twice. there is to be the ability to record these values and display them. BHUPINDER - Original Message - From: Sam Heard sam.he...@bigpond.com To: Bhupinder Singh bobdog at sancharnet.in; Openehr-Technical openehr-technical at openehr.org Sent: Thursday, October 23, 2003 6:36 PM Subject: RE: Pathology requirements TIMED MEASUREMENTS Bhupinder The protocol describes the methods of measurement - each measure can only have one protocol - so this means that the measurement would be entered twice - quite appropriate because it is unlikely that a different method will lead to exactly the same result. Cheers, Sam -Original Message- From: owner-openehr-technical at openehr.org [mailto:owner-openehr-technical at openehr.org]On Behalf Of Bhupinder Singh Sent: Thursday, 23 October 2003 1:12 PM To: Sam Heard; Openehr-Technical Subject: Re: Pathology requirements TIMED MEASUREMENTS Further to what you have stated there will also be events such as sample is single time is same and the test is same but method of reporting and or conducting test is different. Blood Sugar is one example sample is taken and tested on the bedside and sent to a lab also. These events and results need to be accommodated. Bhupinder - Original Message - From: Sam Heard sam.heard at bigpond.com To: Openehr-Technical openehr-technical at openehr.org Sent: Wednesday, October 22, 2003 4:02 PM Subject: Pathology requirements TIMED MEASUREMENTS TIMED MEASUREMENTS The timed nature of specimens is dealt with in the history and event model of the RM and available in the archetype editor. This deals with timed measurements and interval measurements. The idea of a 21 day progesterone is covered in state information relating to the time since the last menstrual period - BUT there is still the idea of an untimed sequence of events where the order is critical. There are also sequenced events when it comes to looking for stool microscopy, occult blood - but these are reported separately and really are administrative rather than of the nature I will describe here. The best examples of this seem to occur in sampling - three samples of CSF - the first, second and third - or shavings for histology looking for depth of tumour. There are more, such as respiratory function tests with particular challenges - and timing is not an issue. These occur one after the other but the sequence is the only thing that is important - not the time - and time would probably be made up. The question is, how do we deal with this. I think we have two choices: 1. We recognise this is a sampling issue and there should be a label on each sample which is transfered to the report - we have sample 1, 2 and 3 with three separate microscopies and cultures in a single composition. This would get around the confusion of trying to deal with this as a timing issue - it would work for any sampling including location. We do not want to compare these CSF samples in queries as equals but we would have some sort of label associated. So, the sample label and order might be part of this - in the request and then in the result. I guess this goes on at the moment. 2. We have a sequence idea in the event model, by using the offset but having 'sequence' as the unit rather than time. This would mean that people did not have to enter spurious times in the data and name the event as Sample 1, which could be misleading. Comments? Cheers, Sam Dr Sam Heard Ocean Informatics, openEHR Co-Chair, EHR-SIG, HL7 Chair EHR IT-14-9-2, Standards Australia Hon. Senior Research Fellow, UCL, London 105 Rapid Creek Rd Rapid Creek NT 0810 Ph: +61 417 838 808 sam.heard at bigpond.com www.openEHR.org www.HL7.org __ - If you have any questions about using this list, please send a message to d.lloyd at openehr.org - If you have any questions about using this list, please send a message to d.lloyd at openehr.org - If you have any questions about using this list, please send a message to d.lloyd at openehr.org - If you have any questions about using this list, please send a message to d.lloyd at openehr.org
