The Importance of Quality-Assurance Methods for Competent Execution, Handling and Structuring of Colon Cancer Screening Programs - the Case of Programs Based on Stool Tests

Screening for colorectal cancer aims at the early detection of early cancer stages in individuals in a defined, otherwise healthy population. In randomized controlled trials it was possible to achieve a clinically and statistically significant reduction of colorectal cancer mortality for those citizens who participated in a quality assured screening program. It is one of the most pertinent goals of quality assurance measures to attain this success in routine settings. As Sir Muir Gray pointed out: All screening programs do harm, some do good as well [1]. Since screening of colorectal cancer is not just the test such as a test for occult blood, quality assurance has to cover all relevant steps of the program (”screening chain”).

Firstly, in order to achieve high participation rates the information offered for all those interested to take part in the program should be of high quality and presented in an understandable way to the lay audience. Secondly, the test chosen for routine screening should be evidence-based and points of test delivery should be clearly defined. Thirdly, the interpretation of the test result has to be ensured in order to detect abnormal test results. The follow up in case of a positive test result has to be organized in a way that timely and accurate verification is possible by specialists. Finally, in order to ensure the benefits of early detection, therapy also has to be in accordance with current treatment patterns ensured by quality indicators. [Table 1] describes frequent hurdles of CRC screening programs.

Table 1 Neuralgic steps of CRC screening programs communication of - relevant steps of the program (such as conductance of the fecal occult blood test) - the program as a whole - the effectiveness for all those participating in the program cooperation/coordination of GP, specialists, hospitals evaluation of the program follow up of patients

Over the years, an evolution of screening efforts can be observed, relevant steps can be depicted from [Fig. 1]. In particular, the introduction of invitation systems in order to raise participation rates, the central coordination and evaluation of these programs and finally the public disclosure of key data are relevant markers of an elaborated screening program. The introduction of those measures should be undertaken together with all relevant stakeholders, namely consumers, patients, health care providers and payers. The final step is the installation of a CRC program which comprises all relevant aspects from screening up to palliative care in case of a fatal disease outcome.

Fig. 1 Evolutionary steps of (many) CRC-sreening programs.

The failure of a colorectal screening program is not confined to a lack of effectiveness. It may also cause more harm than good. While the benefits of the program are confined to a fraction of all participants, all may experience unwanted effects of screening in varying degrees of severity. Potential failures of screening programs are manifold: false positive cases and detection of cases which never would have affected the life of the patient (”overdiagnosis”) are one side of the coin, false negatives the other. While some factors are inherent to screening programs, quality assurance can ascertain the positive effects of screening. In essence all steps of quality assurance should be incorporated into a learning system which gathers information on each step of the program for analysis and further development. It has to be kept in mind that otherwise healthy citizens have a right to expect a screening program which balances benefits and risks in an adequate, transparent way. While these recommendations apply to almost all screening programs, specific considerations have to be kept in mind in the case of screening of occult blood for colorectal cancer.

Prerequisites of a colon cancer screening program are therefore well defined structures of screening test delivery, organization of an adequate follow up combined with constant measurements of both quality of service provision and outcomes ([Table 2]).

Table 2 Best practices for the quality assurance of colorectal cancer screening programs national multidisciplinary guidelines on colorectal cancer screening central coordination introduction of quality indicators central evaluation publication of results/feedback to providers/feedback to clients

The adequate communication of the screening program as a whole as well as of test details are in the centre of attention for quality assurance measures. Etzioni and collegues published in 2006 the results of thorough analysis of routine data of the veterans health administration on CRC Screening. 41 % of patients with positive fecal occult blood testing failed to receive follow up testing, a result which can be expected also in other settings [2]. Critical factors are therefore test interpretation and in particular the organisation of standardized follow up processes in case of positive test results. In order to monitor these processes, the instalment of quality indicators is of highest relevance. The American RAND Corporation and other groups have issued quality indicators for CRC screening. Of particular interest is the combination of quality goals and remuneration of health care providers. Armour and his colleagues were able to demonstrate the positive effect of bonuses to raise participation rates for CRC screening [3]. The extension of this approach to other indicators deserves future attention.

It is beyond doubt that the development of common standards on the quality assurance of screening programs is for the benefit of consumers, patients and providers. It remains to be seen which impact the development of quality assurance guidelines, funded by the European Commission, will have on the further development of colorectal cancer screening programs in Europe. A similar approach has been chosen for mammography screening and has proven to be a significant success. Since such guidelines have not been developed so far by other professional organisations, this step will foster the quality assurance of CRC screening programs.

References

• 1 Gray M. Evidence based health care. Edinburgh, London, New York, Philadelphia; Churchill Livingstone 2001 Second edition
• 2 Etzioni D A, Yano E, Rubenstein L. et al . Measuring the quality of colorectal cancer screening: The importance of follow up.  Dis Colon Rectum. 2006;  49 1002-1010
• 3 Armour B S, Friedman C, Pitts M. et al . The influence of year-end bonuses on colorectal cancer screening.  Am J Man Care. 2004;  10 617-624