Despite the influence of the Brazelton scale, it has some drawbacks. The biggest is that no norms are available. Therefore, as examiners and researchers say that one infant scored higher than another one, there is no standard sample with which to compare. Further, the scores are not completely understood; further testing is required. As for validity, it has "poorly documented predictive and construct validity." It also does not do a good job at predicting later intelligence, although the scale is supposed to assess the "infant's role in the mother-infant social relationship" from which high scores are supposed to presume "high levels of intelligence.".
