Is it possible for research paper to have a similarity of 2 out of 100 using iThenticate? I'm involved in TPC (technical program committee) task for some international conference. In one paper I'm reviewing, I noticed that the similarity index is just 2% using iThenticate which seems impractical (for me).
Though the type/context of the paper is an essay paper, discussing current status and challenges of some phenomenon/technology/topic, there like no graphs and discussion of numerical/simulation results. I'm suspecting whether the authors  are trying to cheat somehow?
Any tips how to proceed since this is my first TPC task?
I don't think I've ever seen an iThenticate paper with 2% similarity. Less than 10% is rare enough.

However: so what? Low similarity isn't a problem, only high similarity is. The latter implies plagiarism, but the former ... I can't think of any way the authors can cheat by having low similarity. If it's a fake paper generated by SciGen then perhaps it would have abnormally low similarity, but you've already ruled that out since you understood the paper. It's also presumably possible to force a paper to have low similarity as well, simply by continuously rewriting the parts that iThenticate flags.

I'd assess the paper on its content and not worry about the similarity.