George, Alexander
2009 (excerpt from 1959, same title)
Quantitative and Qualitative Approaches to Content Analysis

145
“Inferences from content to non-content variables, however, need not always be based on the frequency values of content features. The content term in an inferential hypothesis or statement of relationship may consist of the mere presence or absence of a given content characteristic or a content syndrome within a designated body of communication, It is the latter type of communication analysis, which makes use of “non-frequency” content indicators for purposed of inference, that is regarded here as the non-quantitative or non-statistical variant of content analysis.”

154
There always is a risk in non-frequency research “that a hypothesis formulated early in the course of [the researcher’s] content description will determine what he [sic] subsequently “sees” and regards as significant in the communication.”