Item banks store questions which can then be selected into a quiz. Within a course Canvas reports the statistics for each question when they are used, but these are not linked back to the item bank.
Could we have this developed so that each time a question gets used its statistics are stored with that question in the item bank.
Statistics is all about power and providing confidence. Power increases with increased sample size and over time the "legacy" statistics for a question that is repeatedly used for different student cohorts would enable the construction of repeatable and valid quizzes. When a group of student perform poorly in a quiz - the legacy statistics can confirm that this group of students are poor and not the questions.
You create a question that has poor statistics and you modify that question, repeat comparisons would show if that change has improved the question.