Measuring the observer (Hawthorne) effect on adenoma detection rates

Background and study aims An independent observer can improve procedural quality. We evaluated the impact of the observer (Hawthorne effect) on important quality metrics during colonoscopies. Patients and Methods In a single-center comparative study, consecutive patients undergoing routine screening or diagnostic colonoscopy were prospectively enrolled. In the index group, all procedural steps and quality metrics were observed and documented, and the procedure was video recorded by an independent research assistant. In the reference group, colonoscopies were performed without independent observation. Colonoscopy quality metrics such as polyp, adenoma, serrated lesions, and advanced adenoma detection rates (PDR, ADR, SLDR, AADR) were compared. The probabilities of increased quality metrics were evaluated through regression analyses weighted by the inversed probability of observation during the procedure. Results We included 327 index individuals and 360 referents in the final analyses. The index group had significantly higher PDRs (62.4% vs. 53.1%, P =0.02) and ADRs (39.4% vs. 28.3%, P =0.002) compared with the reference group. The SLDR and AADR were not significantly increased. After adjusting for potential confounders, the ADR and SLDR were 50% (relative risk [RR] 1.51; 95%, CI 1.05-2.17) and more than twofold (RR 2.17; 95%, CI 1.05-4.47) more likely to be higher in the index group than in the reference group. Conclusions The presence of an independent observer documenting colonoscopy quality metrics and video recording the colonoscopy resulted in a significant increase in ADR and other quality metrics. The Hawthorne effect should be considered an alternative strategy to advanced devices to improve colonoscopy quality in practice.

A25 MEASURING THE OBSERVER (HAWTHORNE) EFFECT ON ADENOMA DETECTION RATES: A CASE-CONTROL RETROSPECTIVE STUDY

Background

The effectiveness of colonoscopy screening to prevent colorectal cancer (CRC) is directly linked to its procedural quality. An independent observer (Hawthorne effect) can improve colonoscopy procedural quality metrics, including adenoma detection rate (ADR). However, the results of studies are limited or controversial.

Purpose

We aimed to evaluate the colonoscopy quality metrics in a group of patients undergoing screening or diagnostic colonoscopies under stringent observer conditions.

Method

In a single-center, case–control study, consecutive patients undergoing routine screening or diagnostic colonoscopy were prospectively enrolled. In the case group, all procedural steps and quality metrics were observed and documented, and the procedure was video recorded by an independent research assistant. In the control group, colonoscopies were performed without independent observation. Colonoscopy quality metrics such as polyp, adenoma, serrated lesions, and advanced adenoma detection rates (PDR, ADR, SLDR, AADR), the mean number of adenomas detected per patient (MAP), and the mean number of adenomas and serrated lesions detected per patient (MASP) were compared. The probabilities of increased quality metrics were evaluated through regression analyses weighted by the inversed probability of observation during the procedure.

Result(s)

We included a total of 687 patients (327 cases and 360 controls) in the final analyses. The case group had significantly higher PDRs (62.4% vs. 53.1%) and ADRs (39.4% vs. 28.3%) compared with the control group. The SLDR was also higher in the case group than in the control group, but the difference was not significant (7.3% vs. 4.4%; P = 0.14). The AADR was not significantly increased. After adjusting for potential confounders, the ADR and SLDR were 50% (odds ratio [OR] 1.51; 95%CI 1.05–2.17) and more than twofold (OR 2.17; 95%CI 1.05–4.47) more likely to be higher in the case group than in the control group. The MAP and MASP were significantly increased in the case group compared with the control group (P < 0.001). The regression analyses for both metrics demonstrated the direct and significant association between the Hawthorne effect and elevated MAP/MASP.

Conclusion(s)

The presence of an independent observer documenting colonoscopy quality metrics and video recording the colonoscopy resulted in a significant increase in ADR and other quality metrics. The Hawthorne effect should be considered an alternative strategy to advanced devices to improve colonoscopy quality in routine practice.

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None

Disclosure of Interest

M. Taghiakbari: None Declared, D. Coman: None Declared, M. Takla: None Declared, A. N. Barkun: None Declared, M. Frija-Gruman: None Declared, M. Bouin: None Declared, S. Bouchard: None Declared, E. Deslandres: None Declared, S. Sidani: None Declared, D. von Renteln Grant / Research support from: ERBE, Ventage, Pendopharm, and Pentax, Consultant of: Boston Scientific and Pendopharm

A82 PREVALENCE AND NON-INVASIVE SCREENING FOR CYSTIC FIBROSIS RELATED LIVER DISEASE IN A COHORT FOLLOWED AT A CYSTIC FIBROSIS REFERENCE CENTER

Background

The reported prevalence of cystic fibrosis (CF) related liver disease (CFLD) varies widely based on diagnostic criteria but reaches up to 40% in some cohorts. Furthermore, its clinical impact is significant as hepatic involvement is the 3^rd leading cause of mortality in CF patients and is associated with a lower life expectancy. Due to the heterogeneous clinical presentation of CFLD, clear diagnostic criteria and non-invasive assessment methods are lacking.

Purpose

This study aimed to measure the prevalence of CFLD in a cohort of patients followed at a tertiary CF center.

Method

The files of all patients followed at the CF clinic of the Centre hospitalier de l’Université de Montréal in 2021 were retrospectively reviewed. Imaging reports, histopathology, laboratory values and transient elastography results were assessed. The NIH criteria were used to define CFLD through either presence of one major criteria (abnormal imaging) or two minor criteria (persistently abnormal lab values, hepatosplenomegaly, or transient elastography ≥ 7 kPa).

Result(s)

358 patients were included in our study, 56% male with a median age of 36 years. While mean liver tests were within normal limits (ALT 24 U/L, AST 26 U/L, ALP 96 U/L, GGT 29 U/L), 182 patients (51%) had at least one episode of abnormal liver function tests (LFTs), and 85 patients (24%) had persistently abnormal LFTs. CFLD was present in 42 patients (12%), with 39 patients presenting major criteria and 3 patients presenting minor criteria. In addition, 67 patients (19%) had solely hepatic steatosis. Furthermore, clinically significant portal hypertension and esophageal varices were detected in 50% of patients with CFLD who underwent upper endoscopy (n=20). Median transient elastography value was 5.4 kPa (interquartile range 4.25 kPa) in the 51 patients with exam results, and 32% had values ≥ 7 kPa. Fibroscan values correlated well with the presence of major criteria, with an area under the curve (AUROC) of 0.80 (0.68-0.92, p=0.0007), while non-invasive serological markers did not perform as well (Fib4: AUROC 0.70 (0.59-0.81) and APRI: AUROC 0.69 (0.59-0.80)).

Conclusion(s)

The overall prevalence of CFLD, including hepatic steatosis, was 31% in this cohort. Prompt recognition is important in clinical care in order to prevent hepatic complications from cirrhosis and portal hypertension. The use of Fibroscan seems promising for detecting CFLD.

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None

Disclosure of Interest

None Declared