While ERP is effective for most OCD patients who receive
this treatment, about 25% to 30% of patients who begin ERP
drop out of therapy prematurely. Among those who remain in
treatment, about 80% respond well, yet 20% or more do not.
Therefore, about 50% of patients referred with OCD are not
significantly improved with ERP, and it is important to consider
this alongside the impressive data for ERP's effectiveness.
Substantial effort has recently gone into investigating
factors that might predict poor treatment response. Below, I
describe some of the recent research on predictors of ERP outcome
and consider the following variables: insight into OCD
symptoms, depression, and family expressed emotion.