Is "I don't know" the same as no?

[pingu777]

Just that really. In various situations, does I don't know/ I'm not sure constitute a no?

I use it as a dismissive term.

I tend to find that "I don't know" tends to mean "I know but you / I won't like the answer"

In my job anything that’s not ‘yes’ is no

Eg me -‘are you flossing?’
Typical patient ‘I think so’. Or ‘I hope so’ ‘ummm’ ‘not as much as you want me to ‘ etc. Or sometimes the question is ignored totally

All those responses usually are a cover because the answer is no but they don’t want to admit it

Sometimes it means “ I do know but I don’t feel comfortable or brave enough to say No”