I would generally say it is a positive relationship. Having a mental illness can, but does not always, affect a person's ability to work. I would expect severe or untreated mental illness would account for more sick days than not.
There are stats that could probably be accessed via the net. I know the financial cost of lost work days due to mental health is extremely high.
J
Sounds like you're writing a paper?
I would need more info before commenting luck jo
Can you be more specific? Like what is going on?
In general a person who is suffering with a mental illness that interferes with her ability to work or even get to work is in a position where she needs mental health treatment. Only a Psychiatrist can determine and diagnose what is going on.