Understand the goal line
Each over/under line asks a different question. O1.5 needs at least two goals, O2.5 needs at least three and O3.5 needs at least four.
Research should match the line being reviewed instead of treating all goal lines as the same scoring question.
Review both teams together
Goal-total research should combine both teams scoring and conceding profiles.
A team that scores often may still be part of lower-total matches if the opponent controls tempo or defends well.
Check scoreline distribution
Average goals can be distorted by one 5-0 or 4-3 result. Scoreline distribution helps show whether a pattern is repeated.
Compare how often matches finish around 1-0, 1-1, 2-1, 2-2 and higher totals before drawing conclusions from averages.
Use xG and xG conceded
xG can show whether recent goal totals were supported by chance creation. xG conceded can show whether defensive numbers are repeatable.
When xG and scorelines disagree, the match needs closer context rather than a quick conclusion.
Consider venue and league environment
Home/away splits matter because teams often produce different scoring profiles by venue.
League environment helps anchor the research because some competitions naturally sit higher or lower for goal totals.