John Jerrim

Well, at least in the PISA study from my previous analysis, I put the difference at around 10 PISA test points.

So if you took into account the Welsh language issue, it might boost Wales' performance in literacy up to around the OECD average.

That's still well behind the rest of the United Kingdom, England in particular.

So I think it accounts for part of the difference, but not all of it.

Not exactly.

And it's likely to be a multitude of reasons, right?

So one of the things that you often see with these international studies is people go to their pet explanation as, aha, that's the thing that's driving it.

That's the reason why.

And, you know, in Wales, you can look at things like there being less emphasis on league tables, not measures like Progress 8 that there are in England or whatever.

And all these things could potentially be kind of explanations.

And it's very hard to kind of tease out the impact of one from another.

I mean, there's definitely some credibility to putting that argument forward.

How much of a difference it makes, we don't know.

And it would be surprising if it can explain the entire difference between, you know, Welsh children and English children all the way up to age 15.

So, again, it might be a contributing factor, but no one really knows how much of the difference that can explain between, say, England and Wales.

It's very hard to kind of tease it apart.