[gwern]

It might mean something like the test predicts better than a randomly-selected interview whether a candidate will eventually be hired. The real question is whether the interview here is an unstructured interview or a structured interview. Industrial psychologists have been pointing out for decades that unstructured interviews are awful, even though everyone keeps doing them, so it wouldn't be surprising if they can be outperformed by even a simple checklist or test. (There are similar, somewhat infamous, results for things like judges and parole - where simple linear models can outpredict the experts.)