How useful are anti-ribosomal P antibodies in the evaluation for SLE psychosis?

I do not think they are very useful at all. This may be a controversial opinion, but I think they should be largely retired from clinical practice.

Though somewhat dated, an excellent meta analysis (Karassa et al., PMID 16385548) on this question concluded the following: "This meta-analysis demonstrated with large-scale evidence that the value of anti-P antibody testing for the diagnosis of NPSLE overall or for particular disease phenotypes is negligible."

How could that be? In their evaluation, they found a weighted sensitivity of 26% and 80%, respectively. You may be inclined to say, that's an 80% sensitivity! Not bad! This perspective is common, but belies a misunderstanding of clinical reasoning. To highlight this fundamental misundersta...