Complex sentence: They consist of extreme, maladaptive levels of various personality characteristics or traits, which can be grouped together along dimensions or underlying concepts (e.g. "openness" or "negative affectivity"), based on statistical or theoretical similarities.
Split into simpler sentences: They consist of extreme, maladaptive levels of various personality characteristics or traits. These characteristics can be grouped together along dimensions or underlying concepts (e.g. "openness" or "negative affectivity"), based on statistical or theoretical similarities.