Prospective Comparison of Patient Experience with Colon Imaging Tests

Article Outline

• Abstract
• Subjects and methods
  • Patients
  • Procedure Testing
  • Demographics
  • Experience Questionnaire
  • Statistical Analyses
• Results
• Discussion
• Acknowledgments
• References
• Copyright

Abstract 

Purpose

Patient experience varies with the currently available colon imaging tests, including air contrast barium enema, computed tomographic colonography, and colonoscopy. We examined differences in patient experience with colon imaging tests and whether they varied with gender, age, and race.

Subjects and methods

Patients with fecal occult blood, hematochezia, iron-deficiency anemia, or a family history of colon cancer underwent air contrast barium enema followed 7 to 14 days later by computed tomographic colonography and colonoscopy. Validated patient experience questionnaires that measured the experience for each test and a separate questionnaire that obtained an overall summary measure were administered after testing. Eleven patient experiences including pain, embarrassment, difficulty with bowel preparation, and satisfaction with tests were examined.

Results

A total of 614 subjects completed all 3 imaging tests. The test most patients were willing to repeat was colonoscopy; it also was reported to be the least painful procedure. Patients were least satisfied with air contrast barium enema, and fewer would undergo air contrast barium enema compared with computed tomographic colonography or colonoscopy. There were limited racial and gender differences in perceptions of the tests. Younger adults perceived air contrast barium enema to be more painful than older adults.

Conclusion

Taking into account a wide variety of patient experience measures, patients preferred colonoscopy to air contrast barium enema and computed tomographic colonography. This finding has important implications for physicians considering different colon imaging tests.

Keywords: Air contrast barium enema, Virtual colonoscopy, Computed tomography, Computed tomographic colonography, Colonoscopy, Cancer screening, Patient preference, Colon cancer, Satisfaction

Air contrast barium enema and colonoscopy are commonly used to image the colon to detect polyps and cancers. Computed tomographic colonography (also known as virtual colonoscopy) was introduced recently as an alternative to these more traditional imaging tests. Although several studies have examined the accuracy of these colon imaging studies,¹, ², ³, ⁴, ⁵, ⁶, ⁷, ⁸ quantitative analysis of patient experience with them has been met with conflicting results.¹, ², ³, ⁴, ⁵, ⁶, ⁷, ⁸ Each modality may be associated with some degree of physical discomfort, but physical discomfort alone does not entirely reflect the complete patient experience. In addition, other aspects of patients’ experiences include preprocedure anxiety, use of conscious (moderate) sedation, difficulty with bowel preparation, feelings of embarrassment, or loss of dignity during the test, all of which may affect patients’ well-being, overall satisfaction, and willingness to have repeated tests. Ultimately, such patient-specific factors will impact compliance with recommendations for future testing. In addition, knowledge of patients’ reactions is important when choosing among different examination procedures and when discussing specific testing options with patients.

Previous studies have begun to help understand how patients perceive colonic imaging tests, in particular, air contrast barium enema and colonoscopy.⁹, ¹⁰ For example, it was shown that air contrast barium enema is less painful than colonoscopy.⁹ In another study, although air contrast barium enema was found to be less painful than colonoscopy, patients were more likely to agree to repeat colonoscopy.¹⁰ Recent data reporting on the patient experience with computed tomographic colonography have been mixed.⁵, ⁸, ¹¹, ¹², ¹³, ¹⁴ To the extent that patient preferences with colon imaging tests play an important role in determining future compliance, we examined patients’ experiences undergoing the three currently available colon imaging tests. This study, in which each subject underwent air contrast barium enema, computed tomographic colonography, and colonoscopy, provided a unique opportunity to compare individual patient experiences between tests.

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Subjects and methods 

Patients 

This multicenter prospective cohort study has been described in detail.¹ In brief, the study was designed to compare air contrast barium enema, computed tomographic colonography, and colonoscopy. Inclusion and exclusion criteria have been published.¹

Procedure Testing 

After written informed consent was obtained, air contrast barium enema was performed in the usual fashion¹⁵, ¹⁶ using standard preparation as described.¹ Seven to 14 days after air contrast barium enema, subjects underwent computed tomographic colonography as described.¹ Colonoscopy was performed after computed tomographic colonography as described.¹

Demographics 

Patient preference by demographics was examined. Race/ethnicity was defined as African-American and white because there were too few additional minorities to examine. Age was categorized because individuals screened after 50 years of age represent those at above average risk for colon cancer,¹⁷, ¹⁸ individuals aged 50 to 64 years represent those at average risk or who have already been screened, and individuals aged more than 65 years have access to colon screening through Medicare.

Experience Questionnaire 

A questionnaire was specifically designed with the intent of capturing patients’ experience with each procedure. The questionnaire was generated and validated as follows: Qualitative analysis from 20 patients who had undergone the 3 procedures identified 11 attributes that characterized their perception of their respective procedure. Questions were developed on the basis of these analyses and a prior measure developed by our research group.¹⁰ Cognitive interviews with an additional 20 patients were then conducted to provide a better understanding of patients’ understanding of the questions, the format of the questions, and the feasibility of administering the survey. In addition, four providers also assessed the face and content validity of the survey. Each questionnaire contained 11 items that assessed patients’ perception of pain, worry, difficulty following directions, difficulties with preparations, anxiety of obtaining tests, comfort with procedures, level of embarrassment, willingness to have the test again, level of respect, tiredness from the procedure, level of inconvenience attributed to the procedure, and overall satisfaction with the procedure. Questionnaires were designed such that lower numeric responses (on a scale of 1 to 5; where 1 = totally agree, 2 = agree, 3 = neutral, 4 = disagree, and 5 = totally disagree) were associated with a greater degree of agreement (see supplemental Web material). The final summary patient experience questionnaire asked patients to choose only the single best or worst test but not rate or rank order them.

A research assistant provided questionnaires after completion of each test and after the subject was fully clothed. The questionnaire dealing with colonoscopy was administered only after the subject had fully recovered from conscious (moderate) sedation. The Cronbach alphas for each individual questionnaire associated with a specific screening test ranged from 0.70 to 0.75. In addition, we developed a separate summary questionnaire that specifically asked patients to compare their experience with the three tests, relative to each other. This final questionnaire was given to each subject to take home and fill out between 24 and 72 hours after colonoscopy and was mailed back to study investigators in a self-addressed, stamped envelope. The final questionnaire (“Summary Measure”) was filled out 72 hours after colonoscopy and mailed back.

Statistical Analyses 

To examine overall differences between individuals across the 3 procedures, Friedman’s nonparametric analysis of variance test was used for two reasons. First, all comparisons were paired within subjects where comparisons between the three examinations were assessed. Second, distributions were skewed in the positive direction, thus violating a principal parametric assumption. Post hoc tests were conducted using Wilcoxon pair-wise comparison. Chi-square tests were used to report patients’ experience with the summary measure. Chi-square tests were used to examine racial, gender, and age differences with patients’ experience on the summary measure. To account for the increased risk of capitalizing on chance afforded by the large sample size and number of tests performed, only findings significant at P less than .001 were considered meaningful.

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Results 

A total of 614 patients completed all 3 colon imaging procedures. Indications for inclusion and reasons that subjects did not complete all procedures have been reported.¹ The cohort was typical of one undergoing colon examination for high-risk indications. The mean age of the population was 57 years. Seventy percent of subjects were men. This male predominance was expected, because 2 Veterans Affairs Medical Centers participated in the study. The races of study participants were white (70%), black (24%), and other (6%). Of all 614 subjects who completed all three studies, 581 subjects (95%) returned all 4 of the postprocedure experience questionnaires.

There were significant differences among patients across 8 of the 11 experiences measured (Table 1). For experiences related to discomfort, air contrast barium enema was perceived as the most uncomfortable test. In addition, patients undergoing air contrast barium enema reported a greater level of being worried/anxious, perceived the procedure to be more embarrassing, and perceived the procedure as being more inconvenient compared with computed tomographic colonography and colonoscopy. When questions about satisfaction and willingness to repeat tests were considered, subjects were less willing to undergo repeat air contrast barium enema and less satisfied with air contrast barium enema compared with computed tomographic colonography and colonoscopy.

Table 1. Comparison of Patient Experience for Three Colon Imaging Procedures

	Air Contrast Barium Enema	Colonoscopy	Computed Tomographic Colonography	P Value
Painful	2.90(3)	3.7(4)⁎	3.02(3)	.0001
Worried about the procedure	3.06(3)†	3.22(3)⁎	3.45(4)	.0001
Difficult to follow directions	4.22(4)	4.22(4)	4.25(4)	.94
Preparations unpleasant	2.77(3)	2.67(2)	2.69(2)	.07
Procedure uncomfortable	2.26(2)†	3.46(4)⁎	2.62(2)	.0001
Embarrassed	3.74(4)†	4.06(4)	3.95(4)	.0001
Respect	1.59(1)	1.61(1)	1.54(1)	.53
Willingness to have test again	2.08(2)†	1.78(2)⁎	1.90(2)	.0001
Worn out from procedure	3.22(3)†	3.03(3)⁎	3.57(4)	.0001
Procedure inconvenient	3.08(3)†	3.30(3)	3.33(3)	.0001
Satisfied	2.11(2)†	1.81(2)⁎	1.94(2)	.0001

Median numbers are given in parentheses. Because of the design of the questionnaire, the lower the number, the greater the agreement(see supplemental Web material for the questionnaire).

Patients reported being more worn out from colonoscopy; however, patients reported less pain, being less uncomfortable, and being less embarrassed with having a colonoscopy. They were more willing to have the procedure again and reported more overall satisfaction with having a colonoscopy than with any other procedure.

After patients completed all 3 procedures, another questionnaire (termed the summary questionnaire) that focused on comparison of the 3 tests in aggregate was administered. In this questionnaire, subjects were asked to rate which procedure was most associated with specific patient experiences (Table 2). Air contrast barium enema was perceived as being the most painful test and the least comfortable procedure. Issues related to global satisfaction were notable in that subjects were least satisfied with air contrast barium enema, and moreover the fewest proportion of participants would be willing to undergo air contrast barium enema again. On the summary questionnaire, patients reported less worry and anxiety after computed tomographic colonography than any other procedure (Table 2).

Table 2. Comparison of Patient Experience on Summary Measure

We examined whether there were differences in experience relative to race, gender, and age. There were limited differences between race and gender (Table 3, Table 4). Whites perceived computed tomographic colonography as being more inconvenient than did African-Americans; males were more embarrassed with air contrast barium enema than females. Younger adults (<64 years) reported greater pain associated with air contrast barium enema than older adults; however, older adults were more likely to report no differences across the 3 procedures in terms of pain compared with younger adults (Table 5). Younger adults reported that they were more embarrassed with air contrast barium enema than older adults.

Table 3. Racial Differences in Patient Experience

Procedure Most…	Air Contrast Barium Enema (%)	Colonoscopy (%)	Computed Tomographic Colonography (%)	No Difference (%)	P Value
Painful
White	55.0	11.6	20.4	13.3	.28
African-American	52.7	6.9	22.9	17.6
Worried about the procedure
White	31.5	31.1	3.4	34.0	.02
African-American	19.8	29.4	7.1	43.7
Difficult to follow directions
White	14.4	3.7	1.7	80.2	.22
African-American	9.0	3.0	3.8	84.2
Preparations unpleasant
White	39.0	21.2	5.4	34.4	.72
African-American	38.6	17.5	7.1	37.0
Comfortable
White	10.9	53.3	28.9	6.9	.03
African-American	14.5	50.4	21.4	13.7
Embarrassed
White	35.2	1.5	3.9	59.4	.19
African-American	36.2	4.6	3.1	56.2
Related to increased respect
White	9.6	11.9	7.0	71.6	.50
African-American	9.6	16.8	8.0	65.6
Willingness to have test again
White	3.0	50.9	27.6	18.5	.07
African-American	3.1	58.5	16.2	22.3
Worn out from procedure
White	40.3	29.6	5.7	24.4	.21
African-American	45.2	23.7	9.67	21.5
Procedure inconvenience
White	9.9	19.8	42.0	28.4	.001
African-American	16.2	22.8	23.5	37.5
Least satisfied
White	4.10	5.8	7.8	45.5	.009
African-American	27.9	5.2	15.4	51.5

Chi-square analyses were used to examine racial differences with patients’ experience on the summary measure.

Table 4. Gender Differences in Patient Experience

Procedure Most…	Air Contrast Barium Enema %	Colonoscopy %	Computed Tomographic Colonography %	No Difference %	P Value
Painful
Male	55.1	10.2	21.6	13.2	.96
Female	54.2	10.5	20.5	14.8
Worried about the procedure
Male	28.6	35.7	4.2	31.6	.31
Female	28.9	28.3	4.4	38.4
Difficult to follow directions
Male	14.3	2.4	2.4	81.0	.76
Female	12.6	4.0	2.1	81.3
Preparations unpleasant
Male	43.6	19.9	5.8	30.8	.49
Female	36.9	20.4	5.9	36.9
Comfortable
Male	12.6	50.9	28.1	8.4	.94
Female	11.4	53.4	26.6	8.7
Embarrassed
Male	43.5	1.2	7.1	48.0	.001
female	31.8	2.7	2.2	63.4
Related to increased respect
Male	17.0	10.7	6.9	65.4	.002
Female	6.2	14.2	7.4	72.2
Willingness to have test again
Male	3.7	50.6	31.5	14.2	.04
Female	2.8	53.7	21.8	21.8
Worn out from procedure
Male	40.2	30.5	6.7	22.6	.88
Female	42.1	27.1	6.7	24.1
Procedure inconvenience
Male	13.2	16.2	38.3	32.3	.37
Female	10.7	22.5	36.9	30.0
Least satisfied
Male	39.5	7.8	10.2	42.5	.34
Female	36.8	4.6	9.5	49.1

Chi-square analyses were used to examine gender differences with patients’ experience on the summary measure.

Table 5. Age Differences in Patient Experience

Procedure Most…	Air Contrast Barium Enema (%)	Colonoscopy (%)	Computed Tomographic Colonography (%)	No Difference (%)	P Value
Painful					.0001
<50 y	58.5	13.4	18.3	9.9
51-64 y	57.7	7.8	23.5	11.0
>65 y	42.1	14.3	13.5	30.2
Worried about the procedure					.07
<50 y	32.9	36.4	3.6	27.1
51-64 y	30.2	28.6	4.4	36.8
>65 y	21.8	28.2	4.8	45.2
Difficult to follow directions					.11
<50 y	19.2	2.8	.7	77.3
51-64 y	11.8	4.6	1.9	81.7
>65 y	9.5	3.9	3.9	82.7
Preparations unpleasant					.12
<50 y	47.0	18.9	6.8	27.3
51-64 y	37.6	21.9	5.2	35.3
>65 y	30.8	19.2	6.7	43.3
Comfortable					.007
<50 y	16.2	52.1	26.1	5.6
51-64 y	8.8	55.2	28.4	7.6
>65 y	14.4	42.4	27.2	16.0
Embarrassed					.0001
<50 y	48.9	2.1	7.1	41.8
51-64 y	34.1	1.6	2.2	62.2
>65 y	21.4	3.2	3.2	72.2
Related to increased respect					.09
<50 y	11.4	15.2	10.6	62.9
51-64 y	9.2	10.9	4.6	75.3
>65 y	7.4	13.9	9.8	68.9
Willingness to have test again					.02
<50 y	2.9	50.0	10.6	14.0
51-64 y	2.2	54.3	4.6	18.9
>65 y	5.7	48.4	9.8	27.1
Worn out from procedure					.05
<50 y	42.1	34.3	6.4	17.1
51-64 y	43.1	28.8	5.9	22.2
>65 y	36.5	22.2	8.7	32.5
Procedure inconvenience					.02
<50 y	17.7	14.9	42.6	24.8
51-64 y	10.5	21.5	37.5	30.5
>65 y	9.7	21.8	29.0	39.5
Least satisfied					.02
<50 y	42.8	8.7	8.0	40.6
51-64 y	37.4	4.4	11.5	46.7
>65 y	28.5	7.3	5.7	58.5

Chi-square analyses were used to examine age differences with patients’ experience on the summary measure.

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Discussion 

We examined 3 different imaging tests, each of which was performed in individual patients. This study design was unique because it allowed comparison of the tests with each other by the same patients. Further, the study cohort was large and, therefore, allowed detection of significant differences among the tests. In general, patients preferred colonoscopy to air contrast barium enema and computed tomographic colonography. Satisfaction was greatest with colonoscopy, and more subjects were willing to have colonoscopy again if necessary compared with the other procedures. There were limited racial and gender differences in preferences; younger adults reported greater pain and more embarrassment with air contrast barium enema than did older adults.

Pain is an important side effect of many tests. We found that colonoscopy was perceived to be the least painful test (it had the lowest pain rating on postprocedure questionnaires and was believed to be the least painful of the three tests when they were compared with each other). Our results were consistent with a previous study in which it was reported that patients reported more pain and discomfort after virtual colonoscopy than colonoscopy.¹¹ However, our results regarding pain were different than in prior studies that compared air contrast barium enema and colonoscopy.⁹, ¹⁰, ¹⁹ For example, previous work suggested that there was no difference in pain between air contrast barium enema and colonoscopy¹⁰, ¹⁹ or that colonoscopy was more painful than air contrast barium enema.⁹ We speculate that colonoscopy was perceived to be less painful than the other tests because sedative-hypnotic and pain-relieving medications were routinely administered during colonoscopy. Indeed, it is likely that such medication contributed to some degree of amnesia of the procedure itself. It was noteworthy that with regard to computed tomographic colonography, when asked “I experienced pain while having this procedure,” subjects responded in a relatively neutral fashion (with a score of 3.02 on a scale of 1 to 5).

As far as computed tomographic colonography and colonoscopy are concerned, we observed that over all, patients preferred colonoscopy to computed tomographic colonography. Previous studies comparing computed tomographic colonography and colonoscopy demonstrated that subjects had no preference,⁸ or that computed tomographic colonography was preferable to colonoscopy.⁵, ¹², ¹³, ²⁰ We do not have an explanation for the discrepancy in findings between some of these previous reports and ours. We speculate that differences in questionnaires and method of administering them, variability in administration of conscious (moderate) sedation, and variability in questionnaire validation across various studies are factors for these discrepancies. In addition, although carbon dioxide was allowed in the computed tomographic colonography protocol, it was not used frequently enough to allow us to draw meaningful conclusions. It is possible that use of carbon dioxide would have led to less pain during computed tomographic colonography. Finally, it is important to emphasize that we went to great length to validate our questionnaire and methodology. To our knowledge, previous studies did not execute such effort in their study design.

An important issue in this study was that conscious (moderate) sedation was used routinely in patients during colonoscopy but was not used during either of the other colon imaging procedures. Colonoscopy is more invasive than either air contrast barium enema or computed tomographic colonography, and it could be argued that sedation is required because of the inherent discomfort associated with this procedure. One the other hand, because such sedation is designed to alleviate pain and induce some degree of amnesia, one might argue that it is not surprising than colonoscopy was found to be less painful and more preferred than the other tests. However, we went to the additional effort to ensure that tests were compared by patients after all testing was completed and after the effect of sedation would have worn off.

We designed our questionnaire with the intent of trying to understand why one test might be preferable to another. Colonoscopy was consistently rated less “painful” than either air contrast barium enema or computed tomographic colonography (Table 1, Table 2). A number of other variables (ie, “respect,” “embarrassed,” “worried about the procedure”) were not different for all of the tests. Thus, we postulate that pain and discomfort played a major role in determining ultimate acceptability of the various colon imaging tests.

One of the major obstacles to acceptance of currently available colon imaging studies is colon cleansing and preparation.²⁰, ²¹, ²² We found that preparations for air contrast barium enema and computed tomographic colonography/colonoscopy (the preparation for these tests was the same) seemed to be similarly “unpleasant” (Table 1); further, when compared with one another, preparation for air contrast barium enema may have been somewhat more unpleasant than for the other imaging tests (Table 2). A major advance in the area of colon imaging and screening would be performance of a colon imaging test without cathartic cleansing or with minimal preparation. In this regard, it seems that this may be possible with computed tomographic colonography.¹⁴

Comparison of subject preference for computed tomographic colonography and air contrast barium enema may prove useful as computed tomographic colonography emerges as a defined technology, with potential as a screening tool. Comparison of computed tomographic colonography and air contrast barium enema is not confounded by the use of conscious sedation because neither uses sedative-hypnotic drugs. Compared with computed tomographic colonography, subjects perceived air contrast barium enema to be more painful, uncomfortable, embarrassing, inconvenient, and less satisfying. Further, subjects were more willing to undergo repeat computed tomographic colonography than air contrast barium enema, consistent with previous investigation comparing air contrast barium enema and computed tomographic colonography alone.²⁰

Another factor that influences patient participation in all diagnostic tests is the loss of work time. Patients undergoing colonoscopy routinely receive conscious sedation, which prevents them from returning to work on the same day (and because of a hangover effect, often the following day). In addition, a second individual is usually required to drive the patient home, often requiring the second individual to miss work. We did not evaluate the length of time or the cost of lost time that the patient and the patients’ caregiver accrued in this study, but we speculate that it was likely greater for colonoscopy than other imaging tests.

There were many strengths of the current study, including the methodology used to analyze the patient experience, the high return rate of questionnaires, and the fact that all 3 major imaging modalities were compared within individual subjects. However, there were several limitations of this study. First, the study was performed at multiple sites, and it is possible that differences in patient populations may have been present at different sites. This could have led to local variance in responses and, thus, to bias in aggregate experiences. On the other hand, the contribution of data from multiple sites is likely to enhance the generalizability of our data. It is also important to emphasize that this study examined patients who agreed to participate in a clinical trial. Therefore it is possible that these subjects were biased in their responses. Although we do not believe this to be an important bias, we cannot exclude this possibility. Finally, a strength of the study was that a large number of subjects were examined; this allowed us to detect very small (but statistically significant) differences. Notably, we focused on findings that were significant at the P less than .0001 level, consistent with the notion that such findings were less likely to be spurious. However, whether small differences (eg, in convenience; Table 1) are clinically meaningful could be debated.

Although we did not specifically examine an asymptomatic population and, therefore, are unsure whether we can extend conclusions about patient experiences with colon imaging tests in the population we studied to a screening population, we believe that understanding patients’ experience in the context of the procedures as performed, including satisfaction, pain, and other unpleasant experiences, as well as willingness to undergo repeated procedures, will influence compliance with recommendations for further investigation. Given current suboptimal adherence to colorectal screening programs in the United States,²³ it is critical for health care providers to not only inform their patients about expected experiences during colonic imaging tests but also understand how patients perceive these tests.

In any discussion about choice of a specific test, the cost, sensitivity characteristics of the test, and patients’ perception and tolerance for the test must be considered. A number of prior studies have gone to great lengths to address the sensitivity of various colon imaging tests.²⁴ However, it is also important to consider patient-specific factors given that they are likely to influence the compliance with recommendations for future testing. To this end, we found that colonoscopy is the test most patients preferred and the test most would be willing to undergo again. Further, computed tomographic colonography was also acceptable to most patients. This finding and the others presented in this study have critical implications for practitioners who recommend colon imaging tests for their patients.

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Acknowledgments 

This study was coordinated by the Duke Clinical Research Institute, Durham, North Carolina. We thank all of the study coordinators, nurses, and technical staff, who were devoted to outstanding care for the patients involved in this study. In addition, we acknowledge Dr Steven C. Grambow’s statistical advice regarding the analyses presented in Table 1.

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