Are bootable anti-virus/malware scans as good as the "normal" ones?

I recently started using the various bootable anti-virus/malware scanners, like the Kaspersky's Rescue Disk.

However i am really interested in how do these bootable scans compare to the "normal" Windows run scans.

For example, would a maximum scan from Kaspersky Rescue Disk find as many malware/viruses as a max scan from Kaspersky Total Security?

Assuming both anti-virus/malware scanners are up to date (latest versions and databases), which is expected to reliably find and clean more viruses/malware?

Thank you for helping out

These should be using the same databases and the same engines (especially if the bootable scan does an online update to get the latest), so the results should be similar. A bootable scan should also catch some viruses that may be detectable, but can hook into the system and prevent detection. A runtime scan may catch viruses that can only be detected while running (not sure if those exist).