The BSID has undergone extensive standardization and validation processes. It includes normative data from a large, diverse sample, making it applicable to various populations. The scales have shown high reliability, meaning that they produce consistent results over repeated administrations. Moreover, the BSID has demonstrated strong validity, indicating that it accurately measures what it intends to measure—developmental functioning. These factors make the BSID a trusted tool for assessing infants with developmental concerns.
