Susan Adlis

Initial validation of a diagnostic questionnaire for gastroesophageal reflux disease

OBJECTIVES:Brief, reliable, and valid self-administered questionnaires could facilitate the diagnosis of gastroesophageal reflux disease in primary care. We report the development and validation of such an instrument.METHODS:Content validity was informed by literature review, expert opinion, and cognitive interviewing of 50 patients resulting in a 22-item survey. For psychometric analyses, primary care patients completed the new questionnaire at enrollment and at intervals ranging from 3 days to 3 wk. Multitrait scaling, test–retest reliability, and responsiveness were assessed. Predictive validity analyses of all scales and items used specialty physician diagnosis as the “gold standard.”RESULTS:Iterative factor analyses yielded three scales of four items each including heartburn, acid regurgitation, and dyspepsia. Multitrait scaling criteria including internal consistency, item interval consistency, and item discrimination were 100% satisfied. Test–retest reliability was high in those reporting stable symptoms. Scale scores significantly changed in those reporting a global change. Regressing specialty physician diagnosis on the three scales revealed significant effects for two scales (heartburn and regurgitation). Combining the two significant scales enhanced the strength of the model. Symptom response to self-directed treatment with nonprescription antisecretory medications was highly predictive of the diagnosis also, although the item demonstrated poor validity and reliability.CONCLUSIONS:A brief, simple 12-item questionnaire demonstrated validity and reliability and seemed to be responsive to change for reflux and dyspeptic symptoms.

Development of a digestive health status instrument: tests of scaling assumptions, structure and reliability in a primary care population.

The absence of valid and reliable health status measures for functional gastrointestinal illness has limited research and patient care for this common group of disorders. A self‐report survey has been developed.

Self-reported effectiveness and physician consultation rate in users of over-the-counter histamine-2 receptor antagonists

OBJECTIVE:Decreased physician visits for dyspepsia were predicted with the histamine-2 receptor antagonists (H2RA) release to over-the-counter (OTC) status. The aim of this study was to examine the presentation frequency for dyspeptic complaints before and after the OTC release of the H2RA and the self-reported effectiveness of OTC H2RA.METHODS:Two cross-sectional surveys were used in a community sample. The patients comprised a random age- and sex-stratified sample of 1600 ambulatory adults in 1993 and 1800 in 1997. Self-report, valid mail surveys gathered information on healthcare seeking and gastrointestinal symptoms in 1993 and 1997 and antisecretory use in 1997.RESULTS:Presentation frequency for dyspepsia was 22% in 1993 versus 23.5% in 1997. Only 16% of chronic users of the OTC H2RA obtained complete relief of symptomatic episodes. Use of an OTC H2RA was highly associated with presentation to a physician in the past year.CONCLUSIONS:OTC H2RA infrequently provided the complete relief desired by patients. Presentation frequency to physicians for dyspeptic complaints did not change with availability of H2RA OTC.

Reliability and validity of the digestive health status instrument in samples of community, primary care, and gastroenterology patients

We evaluated a previously reported digestive health status instrument in community, primary care, and gastroenterology practice populations. Multiple types of reliability, validity and responsiveness were assessed to determine the performance of the questionnaire.

A randomized controlled trial comparing a low-residue diet versus clear liquids for colonoscopy preparation: impact on tolerance, procedure time, and adenoma detection rate.

Objective: To achieve an excellent bowel preparation, it is routine to require a clear liquid diet on the day before the procedure. Unfortunately, this dietary modification may be poorly tolerated. We examine whether a change in precolonoscopy dietary restriction can lead to better patient tolerance without compromising examination quality. Methods: This is a prospective, blinded, randomized controlled trial of patients undergoing screening or surveillance colonoscopy. The primary objective measures the effect of dietary modification on bowel prep quality. Secondary endpoints include polyp detection, patient tolerance, withdrawal time, and patient acceptance. A total of 200 patients were randomized to either (a) a low-residue diet for breakfast and lunch the day before the procedure or (b) clear liquids all day before the procedure. All patients underwent an identical low-volume sodium sulfate split prep. Bowel prep quality was scored using the Boston Bowel Preparation Scale (BBPS). A t test with TOST was used for noninferiority. Secondary endpoints were compared using &khgr;2 analysis. Results: Overall, 96.5% of patients had a good or excellent bowel prep (BBPS=6, 7, 8, or 9). LRD prep quality was noninferior to CLD prep quality (LRD 7.8 vs. CLD 8.1). Polyp detection rates were similar (68% vs. 65.4%, P=0.6899). Patient tolerance and acceptance did not differ. Withdrawal times were equivalent between both groups (16.2 vs. 16.5 min, P=NS). Conclusions: Patients allowed to have a limited low-residue diet before colonoscopy achieve a bowel prep quality that is noninferior to patients on a strict clear liquid diet limitation. Furthermore, polyp detection rates, patient tolerance, and patient acceptance were similar between the 2 groups.

1024 Randomized Controlled Trial Comparing a Low Residue Diet vs. Clear Liquids in Patients Receiving a Reduced-Volume Oral Sulfate Solution for Colonoscopy Preparation

Background: For many patients, the bowel preparation prior to colonoscopy is the most difficult part of the procedure. Physical symptoms are significant, and many patients struggle to complete the preparation. Nonetheless, the importance of an optimal bowel clean-out cannot be overstated. Colon polyps, particularly if flat or right-sided, may be difficult to detect even under good conditions; they can be especially challenging to see if the prep quality is poor. To achieve an excellent bowel prep, many practices, including ours, require patients to follow a strict clear liquid diet on the day prior to the procedure. Unfortunately, this dietary modification is perhaps the most daunting part of the entire process. This study examines whether we can identify a bowel preparatory process that continues to provide excellent results and leads to better patient tolerance and acceptance. Aims and Methods: The study is a prospective, blinded, randomized controlled trial of patients undergoing screening or surveillance colonoscopy at our community-based GI practice. The primary objective of this study is to measure the effect of dietary modification on bowel prep quality. Secondary endpoints include polyp detection rates, patient tolerance, and patient acceptance. 200 patients were randomized to either a) low residue diet for breakfast and lunch the day before the procedure, or b) clear liquids all day prior to the procedure. All patients underwent an identical low volume sodium sulfate split prep ( Suprep ®, Braintree Labs.) Bowel prep quality was scored by blinded endoscopists using the Boston Bowel Prep Score (BBPS). A t-test with TOST analysis was used for equivalence. Comparison of secondary endpoints was done using Chi-square analysis. Results: Overall, 86.5 % of patients had a good or excellent bowel prep (BBPS = 7,8, or 9). The BBPS for patients who had a low residue breakfast and lunch on the day prior to the procedure was equivalent to the BBPS for patients on a clear liquid diet (mean BBPS 8.0 vs 8.2). Table 1. Polyp detection rates were similar between both groups (68% vs. 65.4%, p=0.6899). Patient tolerance and patient acceptance did not differ between the two groups, although more patients in the low residue diet group indicated a willingness to use the same preparation again (73.9% vs. 63.7%, p= 0.1013). Table 2. Conclusion: Patients allowed to have a low residue breakfast and lunch on the day prior to colonoscopy achieve an equivalent bowel preparation quality as patients on a strict clear liquid diet limitation. Furthermore, polyp detection rates (including adenomas, flat polyps, and right-sided lesions) were similar between the two groups. Interestingly, tolerance of the two diets was also similar, but there was a non-significant trend towards higher acceptance in the low residue diet group. Table 1. Bowel Preparation Testing for Equivalence