Distinction "prüfen" vs. "überprüfen"

Question

I just read a technical spec in which I found the following sentence:

Weiterhin kann zum Überprüfen der geparsten Dateien ein XML-Schema verwendet werden.

which translates into

"An XML scheme can be used to check the parsed file."

I wondered why "überprüfen" was used instead of "prüfen", as "prüfen" already means to check and "überprüfen" sounds like checking twice. According to the Duden it means to check again or rethink, while "prüfen" means to test or to check. Confusingly the Duden also gives "prüfen" as a synonym for "überprüfen".

So, when to use "prüfen" and when to use "überprüfen"?
Where is the difference?

Answer 1

There's almost no difference, both verbs can be replaced by each other without a significant difference in meaning in most cases. So usually it isn't a mistake to use prüfen instead of überprüfen and vice versa.

To narrow down the slight difference: I would prefer überprüfen to prüfen if it's about verifying or double-checking a certain fact. However, if there's no fact to verify but still to detect/find out, I would use prüfen. But in many cases, the presence of a certain fact may be disputable or depending on other information, so both variants may be possible.

For example, in your example, if the XML file is expected or assumed to be valid, you have a fact to verify, so überprüfen would be the better choice. However, if you don't have any information about that file, I would use prüfen.

Answer 2

Pretty much agree with tohu for daily usage. The different usage & connotation is imo mainly evident in science & industry. Would explain the weird ngrams chart imo.

blue=prüfung, red=überprüfung

On the google trends graph you can see clearly the peak when Fukushima happened around march 2011. Überprüfung has the connotation of a independent 3rd person/institution checking a system while a Prüfung is e.g. a school or phd test inside a institution. The blue google trends line oscillates pretty periodically, at the end of every year there are no Prüfungen, mostly in the middle.

The rise of überprüfen in ngrams is imo linked to the continuous arising of technological systems in the last century and more & more Überprüfungen in our technological society. Here the connotation and meaning of Überprüfung is imo known and clear, esp. in industry/science.

In science you also say gegenprüfen, when several scientist/groups independently check the same hypothesis/theory. Ich prüfe meine Daten/Behauptung vs. Ich überprüfe eine fremde Conclusio/Messdaten. The prefixes gegen/über dont say anything about quality or number of tests, but what it refers to. über simply implies/connotes someone over or outside of the hierarchy of the proved institution/system is checking. In English this distinction doesnt seem to exist according to ger/eng dictionaries.

Your XML-Parser is basically an exterior softare checking your code, so you would say überprüfen. If you "parse" your source code yourself by looking over it and check spelling, prüfen would imo be more correct. But here its really überhairsplitting :)