 The mean coefficient for a standardized test of g is 0.51.A review of 58 studies on biodata found coefficients that ranged from 0.32 to 0.46 with a mean validity of 0.35.The mean validity of interviews was found to be 0.19. research has indicated a validity coefficient of 0.29 for unstructured interviews and 0.31 for structured interviews but interview results can be affected by interviewer biases and have been challenged in a number of different court cases.