Virtually Priceless Thoughts

A colleague asked me how do I categorize structured information today and, as I happened to be drafting another post on the importance of standardized health information (coming soon), I thought it might be good to post a response online rather than just in an email. The question went something like this:

What does discrete data capture mean to you as a physician? Is this different than structured text? And the difference from free text?

For me, discrete data means that information is being stored in a way that is predefined and has computable meaning. Discrete data could have a terminology behind it, such as a problem list with SNOMED codes or it could be data elements, such as birthdate, that have a singular value. Both of these can be acted on in a consistent manner using decision support engines, used to run practice level reports (how many diabetics over the age of 50 are in my practice?), etc.

Structured text is a way of standardizing and speeding up text entry by using some form of macro-like functionality. Type “_RESPN” and you get a long blob of text that outlines what you do in a respiratory physical exam, all with normal findings. (“…Breath sounds normal, no crackles or wheezes heard on auscultation…”). This text is not interpretable (with the exception of natural language processing) by the computer.

Free text is just ASCII or rich text that is typed / dictated / input by the user using phrases and sequencing that is up to the user.

So yes, the three are different — structured text is a quick input method for free text, but it also triggers some standardization in verbage and action (you cannot say what you did not do).

That would answer the question. There are some other aspects to talk about – and some of these might be relevant.

First, discrete data does not mean standardized data. A common EMR feature (and HIS feature) is the ability to locally define data elements – nicely formed discrete data. Data that does not have to conform to any standard. Thus, there are many discrete data elements that cannot be shared, even between users of the same EMR.

Also, one could have another definition of structured text – that would be text that is marked up. Mark up provides some discrete data, if the EMR supported it. Think of how XML works. Readable text can be marked up with meaning. A sentence like:

“The blood pressure is 130/80.”

could actually be marked up behind the scenes like this:

The blood pressure is <systolic blood pressure>130</systolic blood pressure> / <diastolic blood pressure>80</diastolic blood pressure>

The user may not be aware of the mark up or they may do it with key phrases, but the data is then available elsewhere for graphing, trending, etc. and it seems like free text mark up. (NOTE: this may be what some people talk about when they talk about structured text, I am not sure.)

Finally, these categories, no doubt, are somewhat arbitrary and people will either say “what about X” which doesn’t fit into the boxes above or present another way of breaking down types of information. And that, friends, is exactly why I have comments enabled.

Hope this helps.

No related posts.

Related posts brought to you by Yet Another Related Posts Plugin.