Splitting spells in very large or daily datasets

We have written two Stata programs (do-files) dealing with spell data. The first program, splitspells, splits spell data in such a way that every split spell within the same case is either parallel or unique (in respect to the time period covered by the spells). This could be done by splitting each spell in single time-unit splits, a method that is not recommended—or even feasible—for large datasets or daily data, because it produces a maximum of additional records. In contrast, splitspells does the job by producing the least possible number of additional records and is a useful tool in the process of transforming multiple spell-type datasets into “unidimensional” sequence data. The second program, combispells, is used with episode data that are already split. Using existing spell-type variables and user-defined short labels, combispells produces a (labeled) numeric variable and a string variable that show the spell-type combinations occurring within parallel splits of a case. Thus it provides a user-friendly and easy-to-handle tool for the editing, revision, and exploration of spell data.