The Term "TTI Success Insight Personality Tests" (often known as TTI Survey or TTI SI) refers to most products TTI provides.
TTI is a company that develops assessment tools to show an in-depth image of the personality and behavior of the person who answers it in the context of the work organization environment. Each Personality Assessment TTI provides uses these models to analyze the information they gather about the candidates to predict your fit for the position.
Among the main psychological models the TTI SI assessment tools rely on, there are the DISC model, the 12 Driving Forces Model, and Emotional Intelligence (EQ), etc.
The assessment process results is a results paper of the full analysis of the candidate's personality traits, strengths, weak spots, driving forces, emotional intelligence skills, etc.
You can find an official example of the TTI Talent Insight Test results report HERE.
Here's an example of one of the figures presented in the report based on the DISC model: