Let's say the IDF has positively confirmed 17% combatants. The negation of that set is not "Non combatants" but "Not positively identified by the IDF as combatants". which means that some may still be combatants, and most probably some are as the standard here is to confirm names, something hard to do when someone is under the rubble. Therefore the title here which says 83% civilians according to IDF data is simply false.
That's forgetting the other issues with this article (single IDF unit not tasked with research, multiple databases with different numbers, using Hams death data, forgetting about non-Hamas non-PIJ groups, low reputable source, etc) but I am sure that if you can see this misstep you can understand the general value of what you read there