I would like to get a grammatical break-down of the following sentence:

"For the whole of 2003?04 did you and all of your dependants
(including your spouse)?if you had any?have private patient hospital
cover?"

Essentially I would like to know whether grammatically, the sentence
in its current form implies ?a dependant spouse? or whether in means
?all your dependants and your spouse?. How does the term in brackets
relate to the rest of the sentence?

Thanks

In my reading of it, it does refer to a dependant spouse. A person
with a spouse who was not a dependant could answer the question
differently than a person with a dependant spouse.

Someone familiar with the way the military refers to dependants would
have one slant on this wording and Brittany Spears would have another.

Furthermore, the question leaves another situation open to
interpretation, namely how to answer if the dependants had coverage
but "you" didn't, or vice versa. The use of "and" should require all
to have coverage but the questioner may want to address what happens
if some of the interviewees have a mixed bag of coverage.

A Researcher will have an excellent suggeswtion for clarifying the
question, I am sure.

I don't think grammar gives any clear answer in this case.  A
parenthetical expression can be syntactically independent of the rest
of the sentence.  In my opinion, the most likely interpretation is
that the questioner wants the answerer to consider his or her spouse
as a dependent for the purposes of this question, whether the spouse
actually is dependent or not.  In other words, the question is
equivalent to

"For the whole of 2003?04 did you and all of your dependents, where
'your dependents' should be understood to include your spouse, whether
your spouse is actually dependent or not,?if you had any?have private
patient hospital
cover?"

The less likely interpretation would be equivalent to

"For the whole of 2003?04 did you and all of your dependents, where
'your dependents' should be understood to include your spouse only if
your spouse is actually dependent,?if you had any?have private patient
hospital
cover?"

I agree with Efn-ga's first interpretation, grammatically and also
after a search on the the term "non-dependent spouse".  This appears
in relation to insurance coverage, as in the question.  The concept of
"non-dependent spouse" relates to IRS taxation (maybe also state
taxation), in which one has a choice of declaring family members as
dependents.

This site defines the term in this way (3rd paragraph under "dependent
care spending account":
http://www.brynmawr.edu/humanresources/Benefits/flex7.shtml

Here is another site that gives a definition that is rather
equivalent.  The  "non-dependent partner" does not have to be
financial dependent (or even married), but must live with the
principal person and be declared as a partner:
http://www.emeritihealth.org/emeritihealth/participant/1101881004773.htm

I believe this reinforces Efn's interpretation.