Computer Programs for Interrupted Time Series Analysis: I. A Qualitative Evaluation.

Interrupted time series analysis is a method of analysis for longitudinal experiments involving a sequence of observations on a single dependent variable before and after an intervention. The presence of dependency in the data necessitates the use of computer programs for data analysis. Five recently developed programs are evaluated: BMDP (Dixon, 1985), GENTS (Velicer, Fraser, McDonald, & Harrop, 1980), ITSE (Williams & Gottman, 1982), SAS (SAS Institute, 1984), and TSX (Bower & Glass, 1974). Characteristics evaluated include computational features, quality of documentation, and CPU time required.