Well, without a good deal information about the study, i can’t say much. I suspect it has serious methodological and inferential errors.
oF course, that is not to say that if you did take a proper sample of the same population, you would not find people agreeing that ‘online education is less effective’ but then, in a proper sample the number of people who have actually participated in online education tends to approach a very small number, so most of the story is the outsider’s story.
The best evidence that we have of the students in distance learning courses is that overall outcomes have no significant difference, but any professor will say that the highly motivated students usually do better and the unmotivated students tend to drop out.
So… where does that leave distance educators? who knows, but we do know that some students do much better in it. We also know that some professors don’t do particularly well at distance ed, people that want to ‘deliver lectures’ for instance.
As for extra work, properly designed, it isn’t. As for more challenging, some people find shoes with laces more challenging than shoes with velcro, who am i to judge which is better for them.
and really, who doesn’t want more pay, and the inference is supposed to be… if i use technology i get paid more. The truth is that… no, you don’t, you only get paid more if you take on more duties, not if the duties merely get updated to be contemporary.