Assessing the costs associated with promoting colorectal cancer screening in average-risk populations is an integral component of developing and sustaining such programs.27
We conducted a cost-effectiveness analysis within the context of a randomized trial of tailored patient mailings to promote colorectal cancer screening among average-risk adults. This program yielded an absolute increase in screening rates of approximately 6% over a 15-month period, with an incremental cost per patient screened of $94, well within the range of acceptable costs associated with programs to increase the use of proven effective cancer screening services.30
The reasonable incremental costs associated with our intervention support the notion that colorectal cancer screening is a cost effective strategy,7-9
even when including the costs associated with engaging patients to participate in their health care through the use of tailored mailings.
Several prior studies have assessed the cost-effectiveness of interventions to promote colorectal cancer screening.30-34
The cost per additional patient screened for interventions that targeted average-risk, unscreened patients has ranged from approximately $115 to nearly $6,300 (). While these interventions varied in terms of the focus of the intervention and the materials used (e.g. generic mailings, tailored telephone calls, instructional DVDs, provider performance reports), it is important to note how our intervention differed from these prior studies. Most prior studies have generally focused on a single clinic or community health center. In contrast, our study was much larger in scale, involving over 20,000 patients treated by 110 primary care physicians across 11 community-based centers of an integrated private medical group. In addition, the baseline colorectal cancer screening rate in our intervention was over 60%, far higher than the baseline rates reported in prior cost-effectiveness studies.
Summary of Cost-Effectiveness Analyses for Comparable Interventions to Increase Colorectal Cancer Screening
It is crucial to understand how local interventions can be “scaled” to involve larger populations with higher screening rates that are more typical of current practice.35
Our results are encouraging in that we estimated a similar or lower cost per additional person screened compared to other settings with lower baseline screening rates. In addition, to our knowledge our study is the first one that utilized an advanced electronic health record to create an electronic data registry of patients overdue for colorectal cancer screening. This feature may result in significant cost savings compared with older programs that used manual chart reviews to identify patients overdue for screening.32
It is equally important to understand how the costs of our intervention compare with previous research on the overall cost-effectiveness of colorectal cancer screening programs. Frazier et al. used a Markov model to project treatment costs and life expectancy associated with various screening strategies for a cohort of patients starting at age 50 with a baseline screening rate of 60%, closely paralleling the characteristics of our study population.7
The authors estimated that 23.9 additional patients needed to be screened via annual fecal occult blood testing to gain one additional year in life expectancy. The incremental lifetime treatment costs were $672 (2008 dollars) per patient, for a total of $16,060 per additional life year gained. Our intervention would cost approximately $2,247 to increase screening by 23.9 additional patients, or only 14% of the costs estimated by Frazier et al. Based on this comparison, our intervention costs are unlikely to change the overall cost effectiveness of existing colorectal screening programs.
Although our study is strengthened by the randomized design and inclusion of a large patient population, it also has some potential limitations. First, our study was conducted in a more structured setting than many other health care organizations. In particular, integrated medical groups generally provide higher quality care for screening services,36
and so our findings may not readily extend to all other settings. Second, we did not conduct prospective time-motion studies that might have produced more accurate estimates of time costs associated with certain elements of our program such as scheduling colonoscopies. However, these costs were relatively minor in our cost estimates compared to the costs of assembling the data registry and distributing the patient mailings. While our intervention targeted performance of fecal occult blood testing, flexible sigmoidoscopy, and colonoscopy, the primary intervention effect was to increase rates of fecal occult blood testing. We are unable to comment on the cost of a program that would primarily promote performance of colonoscopy. However, it is important to note that despite the preference for colonoscopy among physicians nationally37
and in our study,28
patients often prefer fecal occult blood testing38
and this option is still supported by national guidelines.10
While a large population of patients overdue for colorectal cancer screening could be identified very efficiently with a well-established electronic health record, we did not include the broader costs of implementing such an advanced system, which can be substantial. Therefore, our analyses apply more directly to settings already using a similarly advanced electronic health record system. Finally, future work is needed to establish the cost-effectiveness of sustaining such interventions in the long term and how such estimates would vary as the baseline screening rate of the targeted patient population varies.
Our study findings highlight the potential for a structured quality improvement program involving tailored patient mailings to increase rates of colorectal cancer screening with acceptable incremental costs and cost effectiveness. Future research should assess how these findings can be applied to other health care settings and evaluate whether other interventions can achieve similar or better incremental costs per additional patient screened.