Quantitative and Qualitative Analysis of Fecal Incontinence

Abstract

Fecal incontinence (FI) is an anorectal disorder characterized by the impaired ability to control the release of gas and stool, and for this, there exists a variety of quantifying and qualifying scoring tools. Understanding the complexity of FI symptoms is crucial, and unfortunately, these scoring tools do not always accurately reflect the disease severity of patients nor completely quantify the effect that FI has on their quality of life. This chapter will review the different scoring tools that are used for the quantitative and qualitative assessment of FI. The assessment of quality of life will also be discussed.

Commentary by Ann C. Lowry, University of Minnesota, Department of Colon and Rectal Surgery, Minneapolis, MN, USA

Commentary

• Ann C. Lowry 

A scoring system for fecal incontinence (FI) that incorporates all the relevant factors is simple to complete and interpret which would benefit both clinicians and researchers. An instrument resulting in a single score reflecting both severity and quality of life would be ideal. Unfortunately, the perfect system does not exist. In their excellent chapter, Pang and colleagues provide a thorough summary of available instruments and address the important issue of measurement of severity and quality of life related to the disease. They point out that simplification to a visual analogue scale (VAS) scoring system was not adequate. Further complicating the effort, the surgical, gastroenterology, and gynecology literature all vary in their focus.

Like many functional disorders, it is well established that no objective measure accurately reflects the severity of fecal incontinence. Therefore, severity must be measured through recording of relevant symptoms. As the authors point out, most severity scoring systems include frequency and type of incontinence. It is unclear whether frequency alone is sufficient or if it needs to be addressed in the context of the patient’s bowel habits. Are two episodes of incontinence per week equivalent in patients who have three bowel movements a week and ones who have ten bowel movements a week? Rarely are the amount of incontinence, urgency, awareness, unpredictability, discomfort, and wiping issues included; all of these symptoms have been cited as important issues for patients [48]. Two scoring systems (FISI. and St. Mark) include urgency, and FISI. includes volume of stool loss. Studies show that unpredictability is very distressing to patients but is not included in any of the instruments. While amount seems intuitively to be important, one study showed that it was not a significant factor in distress related to FI in multivariate analysis [49]. Further post hoc analysis revealed that the lack of significance was related to very high correlation with other significant items. Thus, whether quantity of leakage is an important factor is unclear.

Some commonly included items may not reflect severity. An example is the use of pads. Patients may wear pads for the urinary incontinence, and successfully treated patients may wear pads from lack of confidence in their symptom resolution.

Another unresolved issue is whether to use weighting of items to establish a final score. As discussed in the chapter, patients and physicians weigh frequency and type differently. For example, patients rate leakage of liquid stool as more severe, while physicians label leakage of solid stool as more severe [50]. Patients tend to rate items on the impact on the quality of their life, while physicians are more likely to consider the relationship of a symptom to either the degree of anal sphincter weakness or to the difficulty of correcting it.

The collection of data for severity scoring may be through daily diaries, weekly questionnaires, or longer interval recall questionnaires. Many investigators believe that daily diaries are necessary to obtain accurate data, but Noelting and colleagues [51] found a strong correlation between daily diaries and weekly questionnaires. The concern about longer intervals such as the 1-year recall for FISS is that it may not reflect current status or be as responsive to changes related to treatment.

The work on thresholds and minimal important differences (MIDs) is critical to research and approval of new therapies particularly high cost ones. It is possible to have statistically significant outcomes that have little meaning in terms of the patient’s quality of life. In addition, it is important to the design of research studies on FI. These thresholds or MIDs are available for only a few scales.

The wish for the simplicity of a single score drives the combination of severity and quality-of-life items. While correlated, those concepts are independent. Clinicians are aware that incontinence of flatus may be very distressing to one patient but barely noticeable to another. Therefore, the severity items and quality-of-life items need to be scored separately. An option is an instrument such as the Modified Manchester Health Questionnaire which includes both types of items but only scores the quality-of-life items. Presumably the severity items could also be scored if they were validated. At present, it is uncertain if the length of the instrument reduces willingness to complete. The literature supports that condition-specific quality-of-life surveys are more responsive than general or specialized scale. Several studies correlated various severity scales with condition-specific quality-of-life scales . As noted in the chapter, the Cleveland Clinic Florida-Fecal Incontinence Score (CCF-FIS) has had the highest correlation. However, the significance of that is uncertain since the CCF-FIS includes a quality-of-life question.

Data collection is also an issue with quality-of-life instruments. Mail surveys are troubled by lack of response. Kwon and colleagues [52] studied telephone administration and found good correlation although the severity items were scored lower on the written form. Rockwood’s commentary on the article highlights some remaining challenges, however, in survey development and choice of mode of administration.

Clearly, there is still more work to be done to develop the ideal method of evaluating FI severity and the impact on quality of life. Collaboration of the various medical and surgical specialties with interest in pelvic floor disorders, patients, and psychometricians is the most likely to succeed in the development of “ideal” tools for the quantitative and qualitative analysis of FI. The authors’ effort to elucidate the issues is a helpful start to that effort.