What does "their" refer to in this sentence?

No, it refers to the practicionors. Their is a possessive pronoun coming
from the word "they" .

One would guess that "their" does refer to "data".

How so Miller?

their refers to the practitioners.

if you substitute the two words with the as in "the practitioners" and then "the data" for "their" - you'll see that only practitioners makes sense.

I think you're confused because you're reading it as the practitioners collecting data for the sake of collecting data. I think what the sentence is saying is that practitioners should collect data to benefit the critical care unit, and not solely for their own personal information or use.

It could refer to either and fortunately in this case it doesn't change the overall meaning of the sentence.

This sentence is ambiguous and is not good English.

I agree with Miller, when I first read this sentence, my intuition connects the pronoun "their" with the noun "data".

A phrase like "Don't collect the data for the data's sake" is a perfectly reasonable phrase, as is a non-ambiguous phrase using a pronoun like "Don't collect the data for their own sake".

How can you collect data for their (data's) own sake?

"their" is a possessive pronouns like mine, yours, ours, his, hers, whose.

If you are taking data that is outside of the scope of the experiment. For example if you have set up a statistical model to get a representative sample some data may be irrelevant to this model.

This would mean you are collecting data even though it doesn't have any meaning in the analysis of the experiment.

Possessive pronouns can be used for inanimate objects as in the car lost its wheels.

You can also use possessive pronouns for abstract conceps as in "Justice will have its day".

Yes, ebrown, a possessive pronoun claims ownership, so to speak,
but how can data claim ownership to its own data? That doesn't make
sense, so it must be the practicioners who claim ownership to the data,
as it is theirs.

Calamity Jane is right. Their is a plural possessive and is used in reference to to animate beings, not necessarily people but being's, who are able to collect something "for their own sake"

If the sentence was referring to the data - the pronoun would be "its"- denoting the fact that it's inanimate. Data doesn't have the ability to collect at all, much less collect anything "for its own sake".

Aidan,

Data is correctly used as the plural form of the word "datum". The sentence "The data are being collected by the researchers" is perfectly correct English.

Data used to be exclusively plural and in earlier times using data as a singular would have been incorrect. For example, the sentence "The data is being collected by the researches" would have been considered to be incorrect.

I believe times have changed and that now it is proper to use the word "data" as either a singular or plural. In my opinion this is part of the decay of proper English.

Jane,

I am claiming that in the sentence in question, the object of the ownership is the "sake" and the verb is "to be".

You are making this argument for its own sake.

Just to clarify my position again. I think the original sentence is poorly constructed.

The fact that educated, intelligent people for whom English is their first language (I think this is the case for all of us) are having such a disagreement is evidence of this.

I am sorry, ebrown, that doesn't make sense.
You've written yourself "data for its own sake" and that's grammatically
correct. Data for their own sake, is in reference to the researcher or
practicioner.

(English is my second language though)

Can you give me another example where the pronoun "its" is used correctly with a plural noun?

Yes, ebrown!

Every agenda has its own advantages.

ebrown, I'm not disagreeing with you that the original sentence is poorly constructed and confusing. I'm also in agreement that data is the plural of datum.

And when I read it again, in light of that fact - I see your point- it isn't as definitive as I first thought. But I still read it as I first said- that the authors need to resist (instead of avoid) the temptation to collect data for their own personal use or gain. That just makes more sense.

But the sentence as written is pretty awful:
"Although the benefit of the critical care unit is related to the availability of these physiologic data, this should be totally reworded- to something like "For the optimum efficiency of the critical care unit"
practitioners must exercise clinical judgment and avoid this should be "resist"
the temptation to collect data for their own sake" and this should be "for their own personal use or gain".

*I'm still trying to think of a case of using its as a pronoun for a plural. You're probably right about that.

That sentence is actually just as ambiguous as the "data" sentence because "agenda," like "data," is a plural noun (plural of agendum) that has, through common (mis)usage, become a singular noun.

To see what it sounds like when we use "its" to refer to a plural noun, it would be better to use a noun that is incontrovertibly plural: "Snowflakes each have its own shape." You can hear that it's just wrong.

I agree that the "their" in the original sentence refers to data. It may be ambiguously constructed, but the sentence not only makes sense but also refers to an extremely frequent phenomenon in academia. I'm sure any academic would attest that collecting data simply for the sake of collecting data (<--perhaps it would have been better if the original sentence had been written like that) is endemic to all academic disciplines!

"Data for their sake" is basically like "art for art's sake": both phrases are describing a situation in which things are being valued in and of themselves rather than out of any utility. I agree that "data for their sake" is not the best way to render the phrase, but that semantic construct is common enough that I don't see how we could interpret it any other way.