To create a TOC of a selected group or multiple selected groups, in the Three Panes view document contained in the selection(s) will be listed. Select all of the documents and Control-click. Choose the contextual menu option to create a table of contents.
The History view of a database (Tools > History) is a table of contents of the database.
I’m somewhat familiar with qualitative analysis approaches. QDA is often used as a tool to analyze behavior in focus groups used, e.g., to evaluate marketing potentials of a product. I’ve seen it used in development of a legal case through analysis of responses by a forum group to various presentations considered for use in a trial.
Beyond such uses, QDA has been used in a variety of fields including psychology, sociology, philosophy, ethnic studies, literary analysis &c. There are a number of methodologies, some of which, as I studied under Karl Popper, seem non-falsifiable to me. I’m a bit intrigued by the emphasis on the researcher’s philosophy in approaching data, which reminds me of the observational problem of determining the fate of Schrödinger’s cat. Perhaps some form of QDA may be useful in the strange universe of quantum physics. 
I don’t do QDA. There’s a variety of QDA software which hard-codes the researcher’s philosophy of his relation to the data.
If I were to use DEVONthink for QDA, perhaps the annotation script approach by korm and Frederiko could be adapted as such a tool. See Export an index of annotations to a numbers spreadsheet