A further constraint is that the coding procedure results in discrete categories rather than continuously distributed dimensions. Not only is this likely to provide boundary problems, but also it is not at all obvious that discrete categories best represent the concepts that are inherent in attachment security. It seems much more likely that infants vary in their degree of security and there is need for a measurement systems that can quantify individual variation".
A further constraint is that the coding procedure produces distinct categories rather than continuous dimensions, which can lead to boundary problems and raise doubts about whether these categories accurately reflect the underlying concepts of attachment security. A more suitable approach would be to develop a measurement system capable of quantifying individual variations in attachment security.