I've taken at least 5 over the course of my life. Possibly a 6th that I didn't know about (possibly age 5 or 6?), but I know of taking multiple between ages 9

I've taken at least 5 over the course of my life. Possibly a 6th that I didn't know about (possibly age 5 or 6?), but I know of taking multiple between ages 9 through mid 30s. Regardless of the test, the percentile numbers didn't change. I've read people claim on and off for years that you can "study" for them and "improve" your scores, but that's not been my experience. Any variations you get might be slight, but you're extremely unlikely to get any statistical difference... unless.... I had a test at age 9 for a specific 'gifted' program starting in our school district. 2 months later, we moved districts, and I was given the exact same test again. I aced it, because I'd asked my parents some of the questions I didn't understand the first time. I 'confessed'(?) to the test giver in the second district that I'd already had these exact same questions 3 months earlier, which they noted. I'd already 'qualified' after the first test, so again, I don't think there was any significantly different outcome (I 'qualified' after the second test in the new district as well).