If the interview is specifically designed to examine job-related competencies in an organised and methodical way then there is a better chance that it will predict future performance than if it is conducted in a haphazard fashion.
Campion, Palmer and Campion (1997) provided a more detailed analysis of the determinants of the predictive validity of interviews and concluded that predictive validity was improved by certain design characteristics.
Many are measures designed to improve the reliability of ratings and as we know reliability is a necessary condition for validity.
The issue of incremental validity is perhaps less important for selection interviews than it is for other methods of assessment.
However, most people are unclear about what validation studies are and why – or if – they’re really necessary.