Patient Declined to Answer

Meaningful Use requires EHR systems to be able to record language, race and ethnicity, or whether the patient declines to answer the question for any of these demographics.  You can find the text in the regulation here and also below:

(3) Demographics. (i) Enable a user to electronically record, change, and access patient demographic data including preferred language, sex, race, ethnicity, and date of birth.
(A) Enable race and ethnicity to be recorded in accordance with the standard specified in § 170.207(f) and whether a patient declines to specify race and/or ethnicity.
(B) Enable preferred language to be recorded in accordance with the standard specified in § 170.207(g) and whether a patient declines to specify a preferred language.

How would you record that the "patient declined to specify" any of these in a C-CDA document.  If you look carefully in C-CDA and/or QRDA, you do find that there are ways to express "Patient Reason" as the reason why something wasn't done (e.g., an immunization), but that's not the answer here.  These are simply special cases of "I don't know", where you asked the question but didn't get an answer.

In CDA, you represent "I asked and still don't know" as nullFlavor="ASKU" on any code attribute. So, you'd record it as:

<languageCode nullFlavor='ASKU'/>
<raceCode nullFlavor='ASKU'/>
<ethnicGroupCode nullFlavor='ASKU'/>

If you find any other flavor of null, you don't have evidence that the question was asked, and so the reason may be other than "patient declined to answer".