Could your pilot hole be too small?
What kind of screw is that?
The screws are #8 - 3" phosphate power interior wood screws. Their diameter is 3.0mm ignoring threads. But that does not matter, with my little experience in present and past, and after reading internet, have concluded that it's not convenient screwing mdf into the edges, only on its surface (picture below).
In the past I had the same problem, I thought it was because of the 1/4 screws I was using, which were to big, I pre drilled also, but the same thing happened, so I ended drilling with 1/4 bit, and put glue in the hole and on screw, and inserted it as if it was a dowel, I liked this idea, but found more convenient machine screws because their threads are less aggressive and play better with the glue we add. There I used titebond III, don't know how convenient is using regular glue, because we need to consider that are using glue as a filler (very little gap between wood and the screw), titebond did a great job, has good viscosity and strong as hell, even harder than the whole wood.
I will never screw a MDF on its edge, only loosen dowels or box joints and a good wood glue. I was so frustrated to see the thing being splitted.
I see a person recommend this technique (picture above), surely it works, but I still feel like we finish with a fragile structure that will eventually rip, just because the screw is not part of the structure, that's why I recommend gluing the screw or using dowels. When I use a screw as a dowel or a segment of threaded rod, I prepare the rod segment by brushing it with a metal brush, that way the glue will hold with more force, now having three holding factors, the threads of the rod, that they are clean and treated with the brush and a good wood glue.