A comparative study of profoundly multiply handicapped children's scores on the Bayley and the Griffiths developmental scales.

Twenty-five profoundly multiply handicapped children were tested using both the Bayley and the Griffiths scales by the same psychologist, who did not have prior knowledge of their medical and social histories. Scores obtained from the Griffiths scales were consistently higher than those obtained from the Bayley scales. The intercorrelation between the two tests was high. These results suggest that although the two tests may be used interchangeably, their numerical scores are not equivalent when administered to this population.