Budget-impact model for colonoscopy cost calculation and comparison between 2 litre PEG+ASC and sodium picosulphate with magnesium citrate or sodium phosphate oral bowel cleansing agents

Abstract

Objective:

With the availability of several bowel cleansing agents, physicians and hospitals performing colonoscopies will often base their choice of cleansing agent purely on acquisition cost. Therefore, an easy to use budget impact model has been developed and established as a tool to compare total colon preparation costs between different established bowel cleansing agents.

Methods:

The model was programmed in Excel and designed as a questionnaire evaluating information on treatment costs for a range of established bowel cleansing products. The sum of costs is based on National Health Service reference costs for bowel cleansing products. Estimations are made for savings achievable when using a 2-litre polyethylene glycol with ascorbate components solution (PEG?+?ASC) in place of other bowel cleansing solutions. Test data were entered into the model to confirm validity and sensitivity. The model was then applied to a set of audit cost data from a major hospital colonoscopy unit in the UK.

Results:

Descriptive analysis of the test data showed that the main cost drivers in the colonoscopy process are the procedure costs and costs for bed days rather than drug acquisition costs, irrespective of the cleansing agent. Audit data from a colonoscopy unit in the UK confirmed the finding with a saving of £107,000 per year in favour of PEG?+?ASC when compared to sodium picosulphate with magnesium citrate solution (NaPic?+?MgCit). For every patient group the model calculated overall cost savings. This was irrespective of the higher drug expenditure associated with the use of PEG?+?ASC for bowel preparation. Savings were mainly realized through reduced costs for repeat colonoscopy procedures and associated costs, such as inpatient length of stay.

Conclusions:

The budget impact model demonstrated that the primary cost driver was the procedure cost for colonoscopy. Savings can be realized through the use of PEG?+?ASC despite higher drug acquisition costs relative to the comparator products. From a global hospital funding perspective, the acquisition costs of bowel preparations should not be used as the primary reason to select the preferred treatment agent, but should be part of the consideration, with an emphasis on the clinical outcome.