The Item Count for a Data-Field is the number of data 'points' corresponding to it in the central database. For example, if 100 participants had their height measured 3 times by identical procedures, then the Item Count for that field would be 300.

For compound items, such as curves and blobs, a single item actually contains a large number of individual data values, however in general each of these values can only be interpreted sensibly in the context of the container item.