What are the main confounding variables you ask about and monitor in patients with depression and anxiety?

It is critical to rule out bipolarity, which is often missed.

The other major issue is to investigate the possibility of medical comorbidities, which may be causing or contributing to the mood disorder and anxiety.

Check labs and other issues, including imaging.

Review all past records you can find....

I might also screen for ADHD. While often over-diagnosed, if concentration and focus are chief complaints, I’d probe this differential. I use this as a screen but carefully review positives vs. just a score (Adult ADHD Self-Report Scale).