Generalizing From Segments to Sessions: Should It Be Done?

This article addresses two methodological questions that are crucial for research on the natural language in the counseling process: (a) What fraction, or segment, of an interview best represents the entire interview? (b) Do different starting points yield different results? Using a variety of data sets and process measures, we tested segment generalizability in different formats of counseling (individual and family) and with different coding systems (of client and counselor behavior). Results from three studies suggested that, whereas starting points made little difference, generalizing from any size segment to a whole session should not be done when interviews are examined individually. On the other hand, when interviews are aggregated, even fairly small segments can be sampled reliably. In making their own sampling decisions, investigators should consider theoretical and clinical significance and conduct subsample generalizability tests.