My source is unfortunately unverifiable as it's confidential data - I'm not making it up, but maybe it'll be reassuring to confirm my processes to show if there isn't KS2 data on record, that's because there isn't any and not because I'm a bit crap and lazy? 😀
Summer term - export results from the Primary Assessment Gateway. Have already obtained UPNs at this point, so easy to do.
Summer term - CAT4s. Export from Testwise and do a quick analysis, map to the correct results sets and import onto the MIS once admitted (necessary for timetabling in Nova and the Parentpay preadmission sync/etc).
Summer - Holiday - September - importing CTFs from feeders. If I'm lucky, they've remembered to tick the box meaning they actually hold the KS2 data. But it's so patchy, I've never relied upon that. Oh, and because secondaries can't access the youngest of the cohort's data until they've reached 11 years old in GIAP, giving the UPN, still checking the PAG for the very late summerborns.
September onwards - catching up on late starters, in year admissions and missed CATs, exporting NPD KS2 data from GIAP once I get the update on Slack that it's been added. Occasional reassuring of SLT that I've got baseline data on every student, I've already created a series in 4Matrix and it's all been there since the end of the first week of term.
I've already created a marksheet template ready for the data with assorted pupil information columns to include previous school and a column to calculate average KS2 Reading and Maths score to then use two separate nested IF THEN ELSE formulae to place them into the appropriate High, Middle and Lower categories for KS2 and CAT4s (conveniently, the Mean SAS is already on the CAT4 data, which saves me about 90 seconds).
If I then click Calculate and Save, I can export unformatted to Excel and it's easy as anything to see who has KS2 data, who doesn't and whether there are any discrepancies between KS2 and CAT4 bands/the schools where this happens.
It's about 1 in 5 without KS2 data (excluding the in year admissions, where it's more of a 60:40 split of not having data to having it, the rate of absence of data increasing the higher up the year groups you go). It's not a selective area and it's not any more or less diverse than any other state school in the area.