Not really. see if you read the study, the sample group is quite small:
The study fails to mention how many of these participants are Muslim (which is a huge oversight on their behalf since they then later claim in the summary that their study indicates something about Muslims). This not only highlights that the peer reviewing on this particular journal may not have been up to the expected standards (possibly due to shared biases) but also means the best way to estimate the size is to take the estimated percentage of the population (6%) and apply it to the overall pool.
That tells us that the results in the study were probably for 125.1 people, and we have no way of knowing how many of them may have been influenced by other factors shown in the study (being male for example) and that makes up about 0.00000781875% of the global Muslim population. So using this as a measure of Muslims as a whole is slightly less accurate than using myself and Watson as measures for what all Australians are like.
But, the issues with the study do not stop there. The study was conducted over a survey which asked very transparent questions:
Which relies upon an assumption of equal honesty by all participants, and not say it being a matter where some groups know that they’re not supposed to say certain things that they believe in on an official record. They may be raving homophobic lunatics at home or when at a political rally, but know that publicly they need to present an image of being above having biases etc. (Also known as the Shy Tory Factor)
So this could be simply be the adolescent Muslims in Belgium are more honest than the others.
This is why you should always share your sources, they may not be as reliable as you think.