I don ' t see the same thing with their conclusion . It ' s correlation , not causation . Think of it this way if I only look at the behavior of Hispanic transgender teenagers , there will be a lot of inherent commonality in their behaviors and attributes , but can I safely infer anything about them is representative of everyone ? Would all the things that hold true for them hold true for elderly white women ? What ' s your control group in that case ? Are you testing the effects of being Hispanic ? Transgender ? Young ? Each of those will have a number of variables within themselves as well subgroups like young teen vs . older teen , Mexican vs . Salvadorean , etc . . By selecting a very narrow group of already highly similar individuals and then looking for a very broad definition of success metrics , of course you ' re going to find things you can say that will hold true , but that doesn ' t mean your study uncovered a statistically significant result , or even that your conclusion is anything more than conjecture . 70 % of teenagers are sexually active by age 15 is much different than teenagers are more likely to be sexually active than seniors . Had this study taken the approach of players who play at least X matches with fellow clan members are shown to have Y % effect on their win rate , while players who play the same number of matches with friends but are not in a clan have Z % effect , that would be something concrete that shows the effect of clan affiliation , tested against a specific control . It would still be looking at a narrow sample , but at least it would be properly tested for the specific variable they were focused on . A lot of studies have reached more controversial conclusions based on less data , sure . But that ' s mainly because there ' s an audience for it , and scientific rigor has taken quite a nosedive in the noisy , messy world of I can ' t scroll through my Facebook feed fast enough that we live in today . Peer review is so key for scientific studies , but people just aren ' t going to take the time to dive any deeper than the CliffsNotes version of most things because of how much content is being pumped into the world every day . That ' s why listicles , image slideshows , and other quick , snackable content are the majority of the garbage today ' s internet thrives on . It doesn ' t help that the news media is participating in that , looking for ways to fill airtime . So the result ? It ' s the assholes I saw on a talk show yesterday discussing the new study that finds overeating is OK as long as you exercise . Welp , I guess I should go pound a whole cake and then go for a brisk 10 minute walk , then . Science said so !