**Transcript of Cyberseminar**

**ViRec Database and Methods**

**Measuring Laboratory Use and Results Using VA Decision Support System National Extract Data**

**Presenter: Elizabeth Tarlov, PhD**

**March 4, 2013**

**Measuring Laboratory Use and Results Using VA Decision Support System National Extract Data**

**March 4, 2013**

40:01  page 7

Moderator: Hello and welcome to VIReC Database and Methods cyber seminar entitled *Measuring Laboratory Use and Results Using VA Decision**Support System National Extract**Data*. Thank you to CIDER for providing technical and promotional support for this series. Today’s speaker is Elizabeth Tarlov, Associate Director for ViReC here at Hines VA Hospital. Questions will be monitored during the talk and the Q&A portion of Go to Webinar and will be presented to Elizabeth Tarlov at the end of the session. A brief evaluation questionnaire will pop up when you close Go to Webinar. We would appreciate if you would take a few moments to complete it. I am pleased to welcome today’s speaker, Elizabeth Tarlov.

Moderator 2:  Thank you very much Erica and Elizabeth we have turned it over to you now.

Dr. Elizabeth Tarlov: Great, let me close, there we are, and can you see it?

Moderator 2: Yes we can thank you.

Dr. Elizabeth Tarlov: Great, thank you Erica and good afternoon everyone, today’s Cyber Seminar topic as I think you know now is VA DSS LAB Data, this data has been available in nationwide electronic data sets since 2000. We now also have data from the Vista LAB PACKAGE extracted to the CDW and that data I believe goes back to 1999, but I will be focusing today specifically on DSS Data. Here is a bit of a roadmap for today’s session, we will start with an overview and then talk about how to find the information you want in the data files. I will talk about how to use the information in the files to obtain measures of laboratory use and results, and then I will present an example from the literature of the VA study that used DSS National LAB Data. And finally at the end I will list some additional resources that you might find useful. First, we have a couple of questions for you, the audience, and these help us to gauge our audience and the effectiveness of past VIReC communications we have had to the field. 

[Crosstalk]

Dr. Elizabeth Tarlov: I am sorry, do you want me to read the question or?

Moderator 2: Oh yes please go ahead.

Dr. Elizabeth Tarlov: The first question why was Friday a special day in the world of DSS national data extracts? Again, why was this past Friday a special day in the world of DSS National Data Extracts?

Moderator 2: Thank you Dr. Tarlov would you like me to read the answers now or would you like to hold off and touch on that later?

Dr. Elizabeth Tarlov: Go ahead and why do you not read; I do not know how many you have but read a few.

Moderator 2:The first person wrote in, it is the last day available in SAS files now on CDW? I am sorry I have no idea. It was the first day that I realized DSS NDE’s could provide me with the information I was looking for.

Dr. Elizabeth Tarlov: That is great, three different questions and I think it was the first, actually none of those answers were wrong, the one that I was thinking of was and I think it was the first and that is that on March 1, the DSS SAS Data Sets that resided on the Austin Information Technology Center mainframe were due to be removed and I will talk a little bit more about that later. Actually we checked this morning and as of about 9 o’clock this morning in fact they were still there but I would not count on that, they are due to be removed any second. So the second question is have you used LAB data in CDW and here I am referring to the data that is not DSS data, the data I refer to at the outset that is extracted directly from Vista.

Moderator 2: Thank you very much to our attendees you do have the poll question open on your screen now, simply click the circle next to you answer and press submit. It looks like we have already had half of our audience vote so we will give people just a few more seconds to submit their responses, thank you. Great the answers are still streaming in; we have had nearly seventy percent of our audience vote so it looks like we will give people another second or two. And the answers have stopped coming in so I am going to go ahead and close the poll, share the results and Dr. Tarlov you should be able to see those now, if you would like to talk through them real quick.

Dr. Elizabeth Tarlov: Sure, I see that twenty four percent of respondents answered yes to the question about using LAB data in CDW other than DSS, so that is quite a bit of the audience actually had has experienced CDW LAB data that is great. And then seventy-six percent have not, so thank you very much for that, I will go back to showing you my screen hopefully.

Moderator 2: Yes, we can see it.

Dr. Elizabeth Tarlov: I see half of it but I am going to hope for the best, there we go.

Moderator 2: Try advancing it, there we go.

Dr. Elizabeth Tarlov: So we will start with the first section, and overview of VA DSS National LAB Data. What is DSS; well DSS is VA’s managerial cost accounting and executive information system. Its primary purpose is to provide managerially useful information for example about productivity measures, costs per measure of work, quality assessment to VA Managers and other stakeholders including the Under Secretary for Health, the Secretary and Congress. And this is important to know because its primary purpose is what dictates its structure, organization and data definitions and pretty much everything about it. So when you run into things that seem quirky or hard to imagine why they are organized that way, it is helpful to remind yourself of the primary purpose of the data. Understanding this is important to understanding the data that you will be using and what it can tell you. This is basically the conceptual model from which the whole system emanates and it designed to support. Raw materials are the labor, supplies and equipment used to create intermediate products and intermediate products are the goods and services provided during patient care such as x-rays, nursing hours and LAB tests. And then end products are completed patient encounters, the final step. Healthcare providers order LAB tests, x-rays etc for the patients medical treatment. DSS costs the raw materials, measures intermediate product workload, costs per unit, and then applies the cost to each encounter, and the end result is the fully costed encounter.

DSS does not create data, rather DSS brings together data from a whole lot of sources and uses it to produce the needed information and the data can be grouped into three principle types that you can see here by data from financial systems, workload data, I am seeing something funny on my screen. I do not know whether others can see that, it says you may be experiencing network connection difficulties.

Moderator 2: No, we do not see anything off your control panel, but you can minimize that by hitting the orange arrow, there we go.

Dr. Elizabeth Tarlov: So I should just ignore those things. And then patient information that comes from Vista, National Patient Care Database, Patient treatment file etc. every Vista system has a DSS site team and on a monthly basis that team is responsible for submitting the data from Vista. All the data is brought together and processed by DSS to create National Data. The National Data Extracts are constructed from that DSS data. The Laboratory national data extracts are two of five clinical extracts. LAB L-A-B contains LAB workload and costs and LAB Results LAR, L-A-R contains results for a list of now 91 tests. Both LAB and LAR contain test level records that are each record contains information related to a single test. Clinical NDE’s also include these three others that you see listed here; pharmacy, radiology and event capture system. More information about those NDEs is available on the VIReC and DSS websites but I will not be touching on those today. And just to provide a little more contexts, other types or classes of NDE’s are shown here although again I will not discuss those today. Those that contain costs related inpatient and outpatient counters are known as the core extracts, program activity, NDE’s are created to provide information on a particular type of activity that is not otherwise available. And you should know that HERC produces technical guides on the core and some financial extracts and those are available on the HERC internet website. NDE's are extracts from that national data; they are updated monthly or quarterly depending on the type of extract. Files are cumulative year to date, meaning each time the NDE's is built it contains data from the beginning of the fiscal year. Laboratory results data are available from fiscal year 2000 and LAB workload and costs data in the LAV and the ER are available from fiscal year 2002.

DSS and NDE data are available in three formats, as reports and data cubes accessible on the VSSC website. Sequel tables in the CDW, and the SAS data sets which I referred to at the top of the hour that were stored on the AITC mainframe, about to be discontinued, those extracts can now be requested through DART. VINCI has a copy of that data and so they are still available upon request by extract. Also note that there are currently no reports or data cubes that contain Laboratory data. DSS NDE data from fiscal year 2005 forward are stored in a CDW, the data are stored in this relational database and unlike the SAS data sets, and the CDW data are available just from FY 2005 forward as I said. Each NDE table contains all the available data for that and NDE. So for example there is one table that contains the LAB results data for inpatient and outpatient activity for all VISN’s and all years, this is a new format for researchers who have been accustomed to using the SAS data sets. However it is the same data, the data are constructed just as they always have been with the same updates schedule etc. some variable names are slightly different but not so much as to not be recognizable and at the end of the talk in the health resources section, I will provide some reference sources for more information. Now the SAS data sets, this organization that I just mentioned in the CDW tables is different from the SAS data sets, which I mentioned, are now available from Vinci. In those data sets the fiscal year NDE's are actually a collection of files. For each fiscal year data for each NDE's, so lets say data for the LAD and the ER and contained in 21 different files corresponding to 21 VISN’s. One file contains data for one NDE, one VISN and one fiscal year and each of those 21 fiscal year files for LAB and 21 files for LAR contain data for one VISN including inpatients and outpatient services. And what I have just described refers to data from fiscal year 2004 forward in the SAS files. There is yet a different organization for FY 2000 to 2003 that I will not go into but it is described on the VIReC website and our research user guide.

Now I will talk about what is in the data and how to find key information, LAB is a test level data set, there is one record for each complete billable test and it includes those tests performed at the point of care and also some research records. And it identifies, the data and LAB identifies where the test was done and when it was performed. It also contains some calculated tests like LDL cholesterol. Other variables include cost and related information pertinent to accounting and then patient information including identifiers, birthdates, county and zip, enrollment priority and a means test indicator. In the LAB results extract you will have as it sounds, LAB results for patients, specific results for 91 tests and extraction process selects data for those tests only, those 91 tests from Vista and again in that data is patient information including identifiers, birthdates, county and zip, enrollment priority and a means test indicator. You will not find some important data in either the LAB or the LAR NDE's, for example you will not find diagnoses, procedures and other clinical information. You will not find gender or race or ethnicity, in addition any tests conducted that are not patient specific like those done as LAB controls will not be there and then research records unless the patient is considered a VA patient and an encounter is generated in Vista. Here are key test related variables, those not related to cost in other words clinical variables. LAB has a test identifier where the test was performed, a referral flag meaning that the LAB was referred outside of the facility to either another VA facility or a non-VA facility to be performed. Clinic stock code and dates, in the LAB results data there are test identifiers results, the units that the results are reported in and dates and I will go into several of these in more detail.

I am going to talk a bit about test identifiers now in both the NDE's, first LAB, there are several ways to identify records for tests you are interested in and the first identifier is called VA LMIP. LMIP stands for Laboratory management index program, there is a national list, another name for the LMIP is the National LAB Test Code, these codes for each test that is processed a code is entered by the LAB staff. Also what code is used for what test is assigned locally and not standardized and so you can imagine what kind of variation that might produce across facilities. The feed key is a five digit character variable, in most cases it is a LMIP code. The intermediate product number is assigned by DSS based on the LMIP and it is important to know that one intermediate product number may be assigned to more than one LMIP. Test name is another variable, this is a DSS derived intermediate product description, and it is in a freeform text field. The file is maintained by individual site teams and the name assigned to the same test can vary across stations. A group of VA investigators actually looked at this variation, McGuiness at al examined variability in names used by local facilities and this was in a publication I believe it was in 2010 and they found greater variability in some test than others. For example in the case of hemoglobin tests, the authors found 116 different names across 125 facilities. New in 2013 DSS has announced the addition of the LOINC code to the LAB NDE, it has been available for some time in the LAR NDE, but this is new in LAB. LOINC stands for Logical Observation Identifier Names and Codes, it is a universal identifier, it is highly specific in that the specifics that code itself identifies not only the test but the method of analysis and the specimen source and there is a URL for you to learn more about LOINC. Out of these five identifiers in the LAB NDE, the intermediate product number and LOINC will be the most specific and most standardized and what I mean by that is that the same value will refer to the same test across all VA facilities.

In the LAB results extract test identifiers include the DSS LARNO or LAB Results Number, this is the result ID. It is assigned by DSS so the numbers go from one to ninety-one and there is a list of available tests on the DSS website. And then there is the LONIC code also available in the LAR NDE. Now the LOINC was implemented nationwide in fiscal year 2009 and the LAB results records are pulled now since 2009 based on the LOINC code. So remember I said earlier that the LAB results extract contains results for a selected number, 91 currently number of tests from Vista. And the way that those tests are identified for extraction is through the LOINC code. This is different from prior to 2009 when the records were pulled based on the test name and since that test name can vary across facilities and even when a single test name is implemented, it can be changed by individual facilities. And so anytime that would happen there could be a problem with identifying the correct test for extraction. So the implementation of the LOINC is expected to result in a better match between the LAB workload data and the LAB results records than the previous method. This just shows you an extract in an abridged table that again is available on the DSS website, it is a table of tests whose results are currently extracted from Vista and the four columns here are all fields in the LAB result NDE's. So the last you see the test number or the variable name DSS LARNO and the next column shows the DSS test name. Then the units in which the test is reported so in that top row hemoglobin is reported in grams per deciliter and then the LOINC code or codes that are used to extract the records for that particular test name.

Two variables used together provide test results in the LAB results extract. The result variable, this is the result of the test that is identified by the test number on the record, valid values for results are from negative to ten thousand to positive ten thousand including up to four decimal digits. Some results are text or non-numeric and the other variable that is part of the test results is that test unit variable, it is the units in which the test is reported. So based on the previous slide you identify the test records using the test identifier, DSS LARNO and then identify the test results within the record using the result and the test unit variable. A quick example here, lets say that you want to pull all results for the total thyroxine test and you want all results that are done in a specified time period. So first you look at the test table and you find out that the test number for the total thyroxine test is 22, and lets say that you extract all records with that DSS LARNO and on a particular record you go to the result variable, you see a 4.2 on the same record. The test unit says micrograms per deciliter and you concatenate those so to speak and together then you have the result on that record for the thyroxine test. There are some non numeric test results in the data and these are results that are not reported quantitatively for example the one I have shown here is the HIV antibody and these values have been mapped to a numeric value as shown here.

Should I find a one to one correspondence between LAB and LAR records? There are some scenarios where you would not expect to find a one to one correspondence and I am going to spend a minute on this because this is a fairly common question that we get at the VIReC helpdesk. Tests whose values are calculated from other test values and an example is the creatinine clearance, will not have a LAB record for that test. So only the tests from which the calculated values are derived in this case serum creatinine is costed and has an associated record in the LAB NDE. So you will find creatinine clearance results in the LAR records but you will not find a workload record for creatinine clearance in LAB. However you will find the serum creatinine record from which the creatinine clearance was calculated. Another scenario is with what are called send outs, I mentioned it a little bit earlier in regard to a referral flag, and in this case, two records are generated. One reports the inhouse Labor cost of the specimen collection, preparation and shipping and then the other, and this I should note refers to a test that is sent to another VA facility. So there is a second LAB record for the cost of performing the test and in this case, the referral flag would have a Y value when it is sent to another VA source. And let me backup for just a moment because I recall from looking at the slide that I you will find two LAB records even when it is sent to a non-VA source. And the way that you will tell the difference is that you will have in the case where it is sent to another VA facility, the referral flag will be set to Y. 

We will move onto measurement of LAB use and results using the data and I am going to illustrate this using a case scenario and let us say that a question comes to the VIReC helpdesk that says we are conducting a retrospective cohort study of patients with diabetes to study care quality. We would like to measure frequency of hemoglobin A1C testing among our cohort in fiscal year 2010, and the question is can we use the LAB results file to obtain this information. The answer to this is no, you would want to use the Laboratory NDE as the best source of information for fact of LAB as it is sometimes referred to. Remember that this NDE's is used for costing accounting and that means they are not likely to miss a record. There will be one record at least as I said in the prior slide, sometimes there are two for each test and when you are counting tests it is recommended that you use the LAB rather than the LAR. So the goal in this case was to measure the frequency of the hemoglobin A1C testing in the cohort. The procedure, the way that you would go about it is to use the LAB file and you would first want to obtain the feeder key for the intermediate product number for the hemoglobin A1C test, and the way that you would do this is to refer to the DSS intermediate products table on the DSS website. And you would want to search on the name, there is a field in the products table is an Excel file and there is a column called description and you would want to search on the name and all its variants. For example in this case glycohemoglobin, glycosylated hemoglobin, glycated hemoglobin, hemoglobin A1C and you then may want to double check by searching on intermediate product numbers already found. So you search using those names, each one of those will have a intermediate product number, now you have a list of product numbers, you may want to search again on those product numbers because remember that there can be more than one LAB test code to a product number. Now you may be wondering why I have not mentioned LOINC, at this time LOINC is not available in the intermediate products table.

This is an example of what the product table looks like and in the far left column is the feeder system column, it is sorted in alphabetical order by the feeder system when you open it from the website and you want to scroll down to LAB. And you see the intermediate product number; a feeder key, the code there indicates what kind of code is used in the feeder key and then the descriptions. So let’s say you have obtained some feeder key values, you could now search using the intermediate product number that is associated with those feeder keys. In this particular case there is a one to one association between the feeder key and the intermediate product number so you would not if you did search on the product number you would not come up with additional records. But that can be a useful thing to do. Now you have obtained the intermediate product numbers for the hemoglobin A1C test and again in the LAB NDE you want to identify study patients records using the scrambled SSN. So remember this is a study that is looking at care quality for diabetes and they are looking at frequency of hemoglobin A1C testing, so they have a cohort of patients. So first they identify those patient records using scrambled SSN and then limiting the records to FY 2010 records they are going to find several date variables what you want to use is the service date, this is the format that you see here, year, year, year, month, month, day, day and the default when the date is missing is the year and the month that the Vista extract was performed concatenated with ‘01’ for day. Finally you would pull the records with the feeder key equal to the values identified in step one. But you are not done yet, you want to be sure to eliminate duplicates resulting from send out or referral labs and so if you have a record where the referral flag is set to Y, you want to drop that record or you will overcount your hemoglobin A1C test. At that point you will then have all study cohort records for the hemoglobin A1C test performed in fiscal year 2010 data.

Some take home points here, one careful identification of the identifier, the particular test that you are looking for and the manner in which you search is a study specific to some extent but follows the basic steps that I have outlined. You want to watch for date defaults, be aware of those ’01’ on those records on the day field and then do not over count, be sure to look at the referral flag set to Y and drop those records. And just one caveat here related to non-VA LAB results, remember that patients sometimes obtain LAB results from a facility that is closer to home and those results will not be captured in DSS LAB data and they will not be in any computable field likely they are captured in text notes. And so this is not anything that you can do anything about but keep this in mind as you are using the data. So some key messages here, the DSS data are a great resource, they are complex, careful examination is warranted and it is extremely helpful to have someone who is familiar with the clinical side of things. With the Lab tests and the results and the processes that are involved in patient care related to Labs because that will be extremely helpful in interpreting what is in the data. 

40:01  page 7

And for the final substantive section of this presentation, I will provide an example of DSS LAB data use from a VA study. The example I will use is this study by Dr. Ruby Jackson and colleagues from the Washington DC VA, it was published in January 2012 in the *Journal of the American College of Surgeons* and it is called *Hyper Glycemia is Associated with Increased Risk of Morbidity and Mortality After Collectomy for Cancer.*Briefly the objective was to examine the association between perioperative blood glucose level and 30 day outcomes after elective collectomy for colon cancer. This was a retrospective study and the investigators used VA surgical quality improvement data and linked it with DSS LAB data. The primary and secondary outcomes they studied are shown here and the investigators hypothesized that hyperglycemia that is elevated blood glucose would have adverse affects on 30 day outcomes including death, cardiac arrest, surgical site infection and others. In this study blood glucose was the primary independent variable of interest; blood glucose is one of the 91 tests whose results are available in the DSS LAR NDE. The study sample was drawn from colectomies done in fiscal years 2000 to 2005, so those are the dates of the LAR extracts that you would use. Since patients often have more than one blood glucose test in a day, the investigators used the median value of all blood glucose values with the same service date, and they examined the affects of blood glucose on two days separately. The operative day itself and then postop day one, and then they categorized each median blood glucose value as either low, hypoglycemic, normal, normal glycemic, and mild, moderate or severely hyperglycemic. 

This slide lists some of the nuances of working with LAB data and DSS LAB data in particular that the authors would have needed to address. The first relates to LAB and some other clinical data as well and it was mentioned on a previous slide, how to specify the independent variable; here blood glucose, when there are multiple values within the measurement timeframe. So here the authors chose the median but they likely considered other options like highest, lowest, or the mean. They also would have had to deal with out of range values, the article did not specify what the authors considered out of range or how they dealt with those values, but options would have included dropping the values they identified as out of range or even dropping that patient from the cohort. The decision on that of course is dependent on the particular study. And another measurement issue is missing LAB results; the authors excluded patients with no recorded blood glucose values on the operative or postop day. They provided a nice figure that showed how they derived at the cohort and out of about 9600 procedures, 1551 patients had no operative day glucose and over 3000 have no postop day one blood glucose values. So we do not know how many of those tests that were done were but results were missing. They obviously could have been just patients that had no blood glucose tests done at all although that seems somewhat unlikely and there is a way to check. You could use the LAB NDE to identify the LAB test itself and compare that to the LAR and get an idea of the percentage of whether the tests are missing or were not done.

And then a final issue is one that would have not affected this study because the study sample comprised patients in VA inpatient facilities, but it is certainly an issue in the outpatient setting and that is Non-VA LAB tests and I did not mentioned this a few slides ago. And just to remember that patients do obtain these results outside sometimes bring the results back to the VA and these will be found in the Vista LAB package and they will not be extracted therefore to DSS, although the results are sometimes found in the notes or scanned in as an image. That completes the substantive portion of the talk, where to go for more help there are a few slides here and again what you can download for these URL’s on the VIReC website both inter and intranet you will find the DSS Research User Guide. VIReC also has a webpage describing the data transition to the corporate data warehouse and other information on the corporate data warehouse. Two very valuable resources, one is the HSR Data List Serve if you are not subscribed you can join at the VIReC website, this is a discussion among more than 650 data stewards and managers and users and past messages are available in an archive which I find very useful. The archive however is only available on the intranet and the VIReC helpdesk is available by phone and email. The decision support office website has a ton of resources that will help you navigate this data. It is on the internet only and so I am not providing it here on the slide, however you can go to the VIReC internet website to obtain it if you do not already have it and there are multiple resources including a technical guide, layout specifications. You can find all of these in the left navigation pane on the homepage of the Decision Support website and you will see there national reporting. Also you will find the intermediate product table; you will find the list of LAB tests and other things that I have mentioned. CDW SharePoint site if you would like the URL for that email VIReC and the same goes to obtain access to the Vinci SharePoint site. And that concludes my presentation, and I think we have some time for questions.

Moderator 2: We have a few. Are microbiology and atomic pathology and blood bank data available?

Dr. Elizabeth Tarlov: The first two, in DSS data, the first two are not available. Blood bank data is in the DSS data so that you can find but not pathology or microbiology.

Moderator 2: You stated that the LAB extract contains tests marked billable and also those performed at point of care. I have always instructed to mark point of care tests as non-billable unless they are actually performed by LAB staff. Can you please clarify this point?

Dr. Elizabeth Tarlov:I am afraid that I cannot clarify that point that is really an operations thing. But I am glad to know about it and that is something using the data we certainly want to get clarified. There may be DSS people on the call but I would submit that question to the DSS helpdesk, it sounds like an important one.

Moderator 2: Is the addition of the LOINC applicable to only new tests or is it now attached to all previous tests?

Dr. Elizabeth Tarlov: No, in the data I am assuming that is referring to whether there was any kind of retroactive going back and adding the LOINC and so that would be a no.

Moderator 2: Here is another question, why could you not get the same data from LAR versus LAB in the database?

Dr. Elizabeth Tarlov: Get the same data from LAR versus LAB, I need to interpret that a little bit, I am not sure exactly what the requestor is asking but I am going to assume that the question relates to why there would not be a one to one match. And I mentioned a couple of those reasons but including when there can be more than one LAB record for a LAR record. But in terms of LAB records for which you cannot find a LAR record and beyond say calculated test values that I mentioned, there are known missing data in the LAB results and this may by for multiple reasons. One reason was related to the way that the records were extracted from Vista and so I said this earlier that they were extracted using a test name. so the program would say take all records during this specific period of time where the tests name is X and if you had a test name that for some reason the local facility decided that they wanted to change the text name to XA, then that extract was not going to pull that record. And DSS tells us that there were lots of issues related to that and so that is one known reason for missing records. But again in the example I gave I was not able to discern from the information just was not provided in the article what the reason for the tests that were not done and whether the authors took a look at that or not. If my answer is not getting to the question then I encourage the requestor to email the VIReC helpdesk.

Moderator 2: Thank you, why does the referral flag/referral test cause duplicate data in the extract?

Dr. Elizabeth Tarlov: Well because there are two records of separate costs, one is costs for obtaining the LAB specimen and packaging it and sending it out whatever, there is a cost associated with that that is assigned to that LAB and that facility. And then there would be the cost of actually performing the test, getting the test results and that work is done by the outside LAB, VA or Non-VA but outside that facility. So that would  generate a second record and why this gets to the issue at the very outset that I mentioned, remember that DSS is a cost accounting system and so details like that though they make things harder for researchers when using the data, details like that are very important for the accounting.

Moderator 2: The LAB table does not currently contain “LOINC”, so you have any recommendations or suggestions for cross walking between IP numbers or feeder keys and LOINC codes? That is how can we figure out which VA LAB tests corresponds with which LOINC codes for the entire list of LABs provided at a particular stage?

Dr. Elizabeth Tarlov: You know that is a good question and I do not have the answer to it but that is a good question and I would like the answer. So I will check into that and I encourage the requestor to email the helpdesk to identify him or herself and I would be happy to follow up.

Moderator 2: Where can I find the list of 91 tests in the database?

Dr. Elizabeth Tarlov: That is available on the DSS website.

Moderator 2: I think you touched on this but how are LAB tests that are reported in different units at different VA sites dealt with in LAR? Are results converted to a common unit?

Dr. Elizabeth Tarlov: I believe so but I do not have any specific information about that. Yes, one would hope but I do not know about the processes that are involved there. One thing that I could recommend is again the DSS helpdesk is always a good source of information and then also remember that every Vista system has a DSS site team and there is a clinical coordinator in there and that person can also be a font of useful information. Then lastly you are invited to contact the VIReC helpdesk and we can look more into it, I am sorry I cannot answer the question.

Moderator 2: Here is another one, so our cultural results available in any form?

Dr. Elizabeth Tarlov: Culture, culture results.

Moderator 2: Yes.

Dr. Elizabeth Tarlov:Yes, there is microbiology data in the CDW now and if you go to that CDW SharePoint site you can find information about that in their metadata.

Moderator 2: Here is another one, is longitudinal LAB data extractable? For example can the change in a certain LAB value be tracked for a group of patients over a ten-year period?

Dr. Elizabeth Tarlov:Yes that can be done, not unlike the process that I described in the glycohemoglobin example. Lets say you had that cohort and you wanted to track that cohort over ten years, you could certainly do that by using ten years of DSS data. Obviously with all the caveats around that, not all patients are going to be around for ten years, not always getting all their LABs, there can be missing results and what not but definitely that is something that the data can be used for.

Moderator 2: Elizabeth lets take one last one, our HSR and DE folks pulled some LAB data and in our data set over forty five percent was missing. I believe we used a LAB NDE but would it be worth asking CDW to check to see if they have a more complete set?

Dr. Elizabeth Tarlov: I do not have enough information to answer the question. I mean at the outset I would say for example forty-five percent of and I am not sure, forty-five percent is of what.

Moderator 2: The LAB was the white count for example, they typed in.

Dr. Elizabeth Tarlov: Oh the LAB was the white count and somehow you know that forty-five percent MB’s, that again I would refer the requestor to the VIReC helpdesk, I would be happy to followup on it with a little bit more information. Asking CDW, I guess the bottom-line of the question is, is CDW likely to be more complete than DSS, if it is fact of LAB unlikely, but if you are talking about LAB results yes.

Moderator 2: Great, and for our audience if you still have questions that you would like answered, please email VIReC helpdesk at virec@va.gov. And our next session is scheduled for Monday April 1, from 1:00 to 2:00pm eastern and is entitled measuring outpatient pharmacy use in the VA using VA pharmacy data presented by Denise Hines. And I would like to thank everyone...

Moderator: Excuse me, Dr. Tarlov?

Moderator 2: Go ahead Erica.

Moderator: I was just saying I would like to thank everyone for attending today’s session.

Moderator 2: Great, thank you Dr. Tarlov for presenting and thank you Erica for helping out and to anyone that submitted a question that was not answered on the call, I will be passing them along to VIReC and as Erica said you can also write into the helpdesk to receive further assistance. So thanks everybody for joining us today and we look forward to the next Cyber Seminar, have a nice day.

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