Searching Algorithm Help Needed

[Ralph Freshour]

I'm developing a database for a research firm which has data they want
to search for specific criteria against varying base line data - some
of the questions that have been asked to get the raw data (which I
will import into MySQL) are like this:

how often do you use mouthwash?
etc.
etc.

The responses for each question was structured with only 4 answers
from a large group of people:
no answer
low
medium
high

Using various baselines of people, I want to build a query that will
accurately find matches and to also allow me to find 'close' matches
- for example:

if base line #1 is for a consumer who uses mouthwash a 'medium' amount
of times per week, I want to find in the database how many 'hits'
there are for that question - but I also want to capture 'close' hits
like in this example, for this specific question, if the search finds
'low' instead of 'medium' I'd like to count that as a 'close' hit vs a
direct hit (match) - then when the query is over, I'd have say, 80%
matches with (for example) 60% of those direct hits and 20% close
hits - I'm using PHP so I can use that to keep track of direct hits
and 'close' hits.

Am I on the right track here or is there a better or easier way to be
doing this? I hope I've explained this clearly enough!

Thanks...