Maybe, but because of outliers you can't then claim EU elective surgery is cheap when it obviously doesn't apply across the entire block. I'm sure it's cheap in some countries yes.
Would you like me to investigate the propensity of this EU wide, or are you being glib about knowing only a single country and that technically is 100% of your knowledge?
I could probably speak a little to the surrounding nordic countries to be honest, it is fair to assume they have similar systems because they are very similar in many areas.
I think making any broad EU statement even if it applies to many/most is fine.
There will always be some outliers in the data.
There is a similar argument about generalisations on behaviour, ie: statistically average behaviours of people.
You have to be able to talk in broad strokes with the knowledge that it doesn't apply to everyone.