One way to resolve this problem is to contrast data known to have been coded reliably with the data that have not. This tells the analyst whether errors are concentrated in a few categories or cut across all categories. If the latter, the analyst should seriously reconsider the entire design, including the decision to use content analysis. If only a few areas are causing problems, then revising these categories (or the instructions) may solve the problem. (Fox, 1969, pp. 670-72)