There is much current interest in automation of manual elicitation techniques, but little is known about whether automated versions of a technique produce similar results to the manual versions. This paper describes a formal comparison between an item sort, a card sort and a computerized label sort in the same domain. No significant differences were found between the types of knowledge elicited by different types of sort. These findings suggest that computerized implementations of sorting procedures will elicit the same knowledge as manual sorts. This result also emphasizes the need for advice about knowledge elicitation to be based on formal experimental results rather than on assumptions, a-priori reasoning or case studies.