Each score is out of a total of 20. A lower brooding score and higher reflection score are considered more adaptive.
Brooding refers to a maladaptive form of rumination characterized by self-critical, and passive dwelling on negative emotions or situations. It's often linked to asking passive "why" questions e.g. "Why am I such a failure?", without moving toward solutions, thus amplifying distress and correlated with depression and anxiety. As the RRS-10 study notes, it leads to negative affect (emotions) in both the short and long term.
Reflection refers to a more neutral or adaptive form of rumination involving introspection and analysis aimed at understanding one's feelings or situation. It's less emotionally charged and more cognitive, often with a problem-solving focus, e.g. "Why did this happen - what can I learn?". As the RRS-10 study notes, it leads to negative affect (emotions) in the short term, but may reduce them in the long term.