Evaluation of 12 colon-cleansing regimens with single-contrast barium enema.

In a study of patient preparation for barium enemas, 1,435 patients were examined at six different institutions with 12 different preparation protocols. There were 2,870 films evaluated a total of 7,839 times by seven different radiologists who were blind to both the institution and the preparations used. The statistical design, randomization, and analysis of the data obtained was performed by one of the authors, a statistician, and the following conclusions were made: Dulcolax (bisacodyl) plus 2 L tapwater enema is better than all the other protocols in all parts of the colon for both genders and all ages. Dulcolax or castor oil or X-Prep, each with 2 L water enema, are logically similar and better than the other protocols. Water enema only or castor oil only are the least effective protocols.