Doctype in index.php or header.php?

I’m looking at a theme that puts the doctype and all the profile and “head” information in the index.php and then calls in the header.php.

In other themes, like Kubrick, this information is in the header.php and not the index.php, so the index just features a call to the header and then continues with only the post info.

I like the first set, so the most critical info is in the index.php and the header and modular parts are “cleaner” of code, but is there a difference? Is one better than the other?