The distinction (from how I'm reading the GP's comment) is that Group 4 presupposes that data collection is necessary, and seeks to minimize unethical means of collecting that data, while Group 5 presupposes that ethics are paramount, and seeks to establish whether or not data collection can actually be ethical at all.

That is: Group 4 would be more willing to compromise ethics if absolutely necessary to get the data said group needs, while Group 5 would be more willing to compromise data collection if there's no ethical way to collect that data.