Industry payments and auditability of financial conflicts of interest in US gastroenterology and hepatology clinical practice guidelines: a cross-sectional analysis

Abstract

Objective

To assess industry payments to guideline authors, disclosure concordance with actual payments, and the auditability of conflict-of-interest governance in contemporary US gastroenterology and hepatology guidelines.

Methods

Cross-sectional analysis of adult gastroenterology and hepatology guidelines published between 1 January 2019 and 31 December 2024, by the American Gastroenterological Association, American College of Gastroenterology, and American Association for the Study of Liver Diseases. Author disclosures were compared with manufacturer payments recorded in the Centers for Medicare and Medicaid Services Open Payments database during the 36 months preceding guideline acceptance or publication. Payments were considered relevant when originating from manufacturers of therapies recommended in the guideline.

Results

13 guidelines, including 125 author appearances and 102 unique authors, met the inclusion criteria. 61 authors (48.8%) received at least one relevant manufacturer payment, with payments totalling US$1 733 865.58. Median payment among paid authors was US$9644.96. Disclosure discordance ranged from 0% to 85.7% across guidelines. Leadership roles were designated in 2 guidelines, and 4 of 13 met Institute of Medicine transparency standards.

Conclusion

Financial relationships between guideline authors and manufacturers of recommended therapies were common, and many guidelines lacked governance structures permitting external audit. Standardised leadership designation and transparent author-level disclosure may strengthen credibility of future guidelines.

WHAT IS ALREADY KNOWN ON THIS TOPIC

• Financial conflicts of interest among guideline authors are common, but contemporary specialty-specific data in gastroenterology and hepatology are limited.

WHAT THIS STUDY ADDS

• Nearly half of author appearances on recent US gastroenterology and hepatology guidelines received relevant manufacturer payments, disclosure discordance was frequent, and only 4 of 13 guidelines met assessed transparency standards.

HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY

• Guideline developers should adopt standardised, author-level, externally verifiable conflict-of-interest reporting and clearly designate leadership roles.

Introduction

Clinical practice guidelines play a central role in shaping diagnostic and therapeutic standards, quality metrics, and reimbursement in healthcare. Their credibility derives not only from evidentiary rigour, but also from established processes for assessing, managing, and disclosing conflicts of interest (COI) among guideline authors.^1–3 In 2011, the Institute of Medicine (IOM) proposed standards to safeguard guideline credibility through transparent disclosure, COI management, and majority COI-free panel composition.¹ Yet, subsequent evaluations across specialties have demonstrated that adherence to these principles remains variable and often incomplete.^4–10

For subspecialties like gastroenterology and hepatology—characterised by substantial pharmacological innovation and commercial investment—ensuring transparent COI disclosure and management is critical.^{1 2} Prior studies have found that industry payments to gastroenterology guideline authors are common and disclosure is poor.^11–13 However, many of these studies were conducted over a decade ago prior to the approval of several newer therapies that now shape guideline-directed care, including Janus kinase inhibitors and interleukin-23 inhibitors for inflammatory bowel disease (IBD), sphingosine-1-phosphate receptor modulators for ulcerative colitis (UC), and emerging therapies for metabolic-dysfunction associated steatotic liver disease. Additionally, no prior study, to our knowledge, has specifically assessed industry payments originating from manufacturers of gastroenterology therapies recommended within the guideline itself, which is an important distinction with implications for COI severity. Lastly, whether the governance architecture of gastroenterology and hepatology guidelines are sufficiently structured to permit external auditability of financial relationships is poorly understood.^1–9

Gastroenterology practice guidelines provide an informative ecosystem to examine these important unknowns because they span clinical domains with markedly different therapies, ranging from markets dominated by newer branded drugs to those consisting primarily of older multisource generic drugs, while operating under heterogeneous governance frameworks across overlapping societies. In this study, we examined contemporary US adult gastroenterology and hepatology guidelines to assess relevant industry payments to guideline authors, disclosure concordance with actual payments, repeat authorship concentration, and adherence to IOM transparency standards.

Methods

Study design and guideline selection

We performed a cross-sectional analysis of adult gastroenterology and hepatology clinical practice guidelines published between 1 January 2019 and 31 December 2024. Two investigators abstracted data using a prespecified framework, and a third investigator independently verified all extracted data prior to analysis. Discrepancies were resolved by consensus review of original source documents.

We included guidelines issued or formally endorsed by the American Gastroenterological Association, the American College of Gastroenterology, and the American Association for the Study of Liver Diseases that made a recommendation for at least one pharmacological agent. These societies were selected because they produce most pharmacological clinical practice guidelines in US gastroenterology and hepatology. We excluded documents limited to screening, diagnosis, lifestyle modification, or procedural guidance only. Data collection was conducted between January and March 2025. This study was completed in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline (online supplemental file S1).

Data extraction and COI classification

For each guideline, we extracted author-reported financial COI disclosures verbatim from the guideline manuscript and associated appendices or supplementary materials. We classified financial COI status as (a) reporting at least one financial relationship, (b) explicitly reporting no financial relationships, or (c) not specified when a disclosure section was present but individual author-level COI were not itemised. We recorded leadership roles only when explicitly designated in the published guideline and were not inferred. We extracted all drugs mentioned in the text or treatment algorithms (online supplemental table S1).

Manufacturer attribution and Open Payments linkage

We mapped each recommended drug to its manufacturer using the Food and Drug Administration Orange Book and Purple Book databases during the COI window. This window was defined as the 36 months before the guideline acceptance date when available or, if not reported, the publication or online date, consistent with International Committee of Medical Journal Editors disclosure standards.¹⁴ For multicomponent regimens, each branded component was evaluated separately. When no single branded manufacturer could be attributed to a therapy because the product was available from multiple generic manufacturers, the marketing entity was categorised as ‘multiple’. When clear parent–subsidiary relationships existed based on publicly available manufacturer and corporate ownership information, we treated manufacturer names as equivalent for disclosure matching.

Next, we searched the Centers for Medicare and Medicaid Services Open Payments database for general and research payments from manufacturers of guideline recommended drugs to guideline authors during the COI window, which we defined as relevant manufacturer payments. Payments were defined at the manufacturer level rather than the product level because product-specific reporting fields in Open Payments are inconsistently populated. Some payments were marked as having a related product, but the corresponding product name or therapeutic area fields were blank or only partially completed. Authors not captured in the Open Payments database, including non-US-based physicians, were classified as non-evaluable for author-level concordance analyses but retained in guideline-level summaries. Author identity was confirmed using full name, institutional affiliation, state of practice, and National Provider Identifier when available for US-based health professionals. Some guideline authors were non-US physicians or non-physician contributors and therefore were not identifiable within Open Payments. We also identified associated research payments reported in the Open Payments database for which guideline authors were listed as principal investigators during the same COI window. These payments were used to assess institutional industry-funded research exposure, defined as manufacturer-funded research payments directed to institutions (eg, universities, hospitals, or affiliated research centres) where guideline authors served as listed principal investigators.

Disclosure concordance definitions

We assessed disclosure concordance by comparing disclosures and payments. We considered a disclosure to be concordant if a guideline author with a relevant payment explicitly disclosed that manufacturer relationship in the guideline or the absence of both a relevant payment and corresponding disclosure. We considered a disclosure to be under-reported if an author received a relevant manufacturer payment without explicit disclosure of that manufacturer relationship in the guideline. Over-reporting was defined as disclosure of a relevant manufacturer relationship without a corresponding relevant manufacturer payment during the COI window. Institutional research payments were not incorporated into author-level concordance determinations.

Transparency standard assessment

We then assessed guideline-level compliance with IOM Standards 1 and 2 using prespecified binary criteria based exclusively on published material in the guidelines.¹ Standard 1 was coded as met when a disclosure statement was present. Standard 2a, requiring chair or co-chair COI-free status, was evaluated only when leadership roles were explicitly designated and was coded as met only if all designated chairs or co-chairs were reported as having no COI. Standard 2b, requiring a majority of the panel to be COI-free, was coded as met only when author-level disclosures permitted determination that a majority of panel members reported no COI. When compliance could not be definitively determined from published materials, the standard was coded as not met. Overall compliance required fulfilment of all applicable standards.

Statistical analysis

The unit of analysis was the guideline. Authors appearing on multiple guidelines were treated as separate observations because COI windows and recommended manufacturer sets differed across guidelines. Authors with non-itemised disclosures were excluded from author-level concordance analyses but retained in guideline-level summaries. Analyses were descriptive. Categorical variables were reported as counts and percentages. Continuous payment data were summarised using medians and IQRs because of right-skewed distributions. No clustering adjustments were applied because the analysis was descriptive and not inferential. Analyses were performed using Microsoft Excel V.16.0.

Results

13 adult gastroenterology and hepatology guidelines published between 2019 and 2024 met inclusion criteria (table 1). Nearly half were published in 2023–2024 (6 of 13, 46.2%). Sponsoring societies included the American Gastroenterological Association (5 of 13), the American College of Gastroenterology (3 of 13), the American Association for the Study of Liver Diseases (2 of 13), and jointly sponsored documents (3 of 13) (table 1). Disease domains comprised IBD (4 of 13), irritable bowel syndrome (IBS) (3 of 13), hepatitis C virus infection (2 of 13), steatotic liver disease (2 of 13), chronic idiopathic constipation (1 of 13), and Helicobacter pylori infection (1 of 13) (table 1). Across all guidelines, there were 125 author appearances representing 102 unique authors, of whom 23 (22.5%) contributed to two or more guidelines. The median number of authors per guideline was 7 (IQR 6–8) (table 1).

Table 1. Key characteristics of included guidelines and authors.

Characteristic	Value
Total guidelines, n	13
Publication years, n (%)
2019–2020	4 (30.8)
2021–2022	3 (23.1)
2023–2024	6 (46.2)
Sponsoring society, n (%)
AGA	5 (38.5)
ACG	3 (23.1)
AASLD	2 (15.4)
Joint society guidelines	3 (23.1)
AGA–ACG joint guideline	1
AASLD–IDSA joint guideline	2
Guideline type, n (%)
Clinical practice guideline	8 (61.5)
Practice guidance	2 (15.4)
Living guideline	2 (15.4)
Focused pharmacological update	1 (7.7)
Disease domain, n (%)
IBD	4 (30.8)
IBS	3 (23.1)
HCV	2 (15.4)
Steatotic liver disease (NAFLD/MASLD)	2 (15.4)
Chronic idiopathic constipation	1 (7.7)
Helicobacter pylori infection	1 (7.7)
Author characteristics
Total guideline authors, n	125
Total unique guideline authors, n	102
Median authors per guideline (IQR)	7 (6–8)
Authors appearing on ≥2 guidelines, n (%)*	23 (22.5)

^*Percentage calculated among unique guideline authors.

AASLD, American Association for the Study of Liver Diseases; ACG, American College of Gastroenterology; AGA, American Gastroenterological Association; HCV, hepatitis C virus; IBD, inflammatory bowel disease; IBS, irritable bowel syndrome; IDSA, Infectious Diseases Society of America; MASLD, metabolic dysfunction-associated steatotic liver disease; NAFLD, non-alcoholic fatty liver disease.

Across 125 author appearances, 61 (48.8%) received at least one relevant manufacturer payment, with payments totalling US$1 733 865.58 (table 2). Among authors receiving relevant payments, the median relevant payment was US$9644.96 (IQR US$1308.62–US$32 384.63) (table 2). Most payments were general payments, with consulting and honoraria accounting for 79.9% of total relevant payments (table 2). Four of seven chair or co-chairs (57.1%) received relevant manufacturer payments (table 2). At the guideline level, the proportion of author appearances receiving relevant manufacturer payments ranged from 0% (G10) to 100% (G11). Total relevant payments across all authors within a guideline ranged from US$0 to US$597 635.07 (G3) (table 3). Median relevant payment among paid authors within guidelines ranged from US$444.67 to US$96 707.58 (table 3).

Table 2. Pooled Open Payments to guideline authors from manufacturers of guideline-recommended therapies across 13 guidelines.

Authors receiving relevant manufacturer payments, N (%)*†	61/125 (48.8)
Chairs/co-chairs receiving relevant manufacturer payments, N (%)*†	4/7 (57.1)
Total relevant manufacturer payment, US$†	1 733 865.58
Median relevant payment per paid author (across all guidelines), US$ (IQR)†‡	9644.96 (1308.62–32 384.63)
Payment composition, % of total relevant payments dollar value
Research	3.7
General – consulting	48.4
General – food and beverage	2.8
General – honoraria	31.5
General – other	13.6

^*Authors contributing to multiple guidelines were treated as separate observations.

^†Relevant payments were defined as payments from manufacturers of products specifically recommended within each respective guideline.

^‡Median and IQR were calculated among authors receiving non-zero relevant payments.

Table 3. Author-level total and relevant Open Payments from manufacturers of products recommended within each guideline.

Guideline ID	Authors receiving relevant manufacturer payments, n (%)	Chairs/co-chairs receiving relevant manufacturer payments, n (%)*	Total relevant manufacturer payment, US$†	Median relevant payment per paid author, US$ (IQR)‡	Relevant manufacturers with payments to authors, n	Authors with under-reporting, n (%)§	Authors with over-reporting, n (%)¶
G1	6 (40.0)	N/A	117 773.99	20 094.24 (18 068.00–26 373.09)	3	4 (26.7)	0 (0)
G2	4 (57.1)	N/A	219 978.06	22 534.59 (11 607.43–65 921.67)	2	0 (0)	0 (0)
G3	6 (85.7)	N/A	597 635.07	96 707.58 (81 361.63–121 112.21)	4	6 (85.7)	0 (0)
G4	2 (33.3)	N/A	54 523.14	27 261.57 (19 449.25–35 073.90)	3	2 (33.3)	0 (0)
G5	2 (33.3)	N/A	9016.70	4508.35 (2266.68–6750.03)	2	2 (33.3)	0 (0)
G6	9 (56.3)	3/3 (100.0)	26 054.32	2731.60 (236.10–4013.57)	3	5 (31.3)	0 (0)
G7	9 (32.1)	1/4 (25.0)	99 070.12	8411.35 (3683.37–9346.43)	3	7 (25.0)	4 (14.3)
G8	2 (28.6)	N/A	26 340.62	13 170.31 (6591.76–19 748.86)	3	1 (14.3)	0 (0)
G9	5 (62.5)	N/A	223 643.74	15 580.51 (9886.50–98 751.15)	2	1 (12.5)	0 (0)
G10	0 (0)	N/A	0.00	N/A	0	0 (0)	0 (0)
G11	7 (100)	N/A	134 731.50	1308.62 (36.77–14 415.45)	6	6 (85.7)	0 (0)
G12	4 (80.0)	N/A	219 988.99	43 650.82 (40 714.14–57 933.93)	4	1 (20.0)	0 (0)
G13	5 (71.4)	N/A	5109.33	444.67 (35.39–773.44)	4	3 (42.9)	0 (0)

Note: For G10, the guideline included a disclosure statement but did not itemise author-level disclosures. Although some authors had Open Payments entries during the COI window, none involved manufacturers of therapies recommended in the guideline.

^*Chair/co-chair designation based strictly on explicit labelling within the published guideline.

^†Relevant manufacturer payment defined as ≥1 transfer of value from a manufacturer of a pharmacological therapy explicitly recommended in the corresponding guideline during the prespecified 36-month COI window.

^‡Median and IQR calculated among authors receiving ≥1 relevant manufacturer payment.

^§Under-reporting defined as receipt of a relevant manufacturer payment without disclosure of the corresponding manufacturer relationship in the guideline.

^¶Over-reporting defined as disclosure of a relevant manufacturer relationship without a corresponding relevant manufacturer payment during the prespecified COI window.

COI, conflict of interest.

Among authors contributing to multiple guidelines, 17 of 23 (73.9%) received relevant manufacturer payments, compared with 44 of 79 (55.7%) authors appearing on only one guideline (table 1; online supplemental table S2). Because leadership roles were explicitly designated in only two guidelines (table 4), evaluation of leadership-associated COI patterns and repeat authorship within formal leadership structures was limited.

Table 4. Guideline-reported conflict of interest disclosure characteristics.

Guideline ID	Year	Sponsoring society ID/title	Disease domain	Total authors, N	Authors with reported COI, n (%)*	Chairs/co-chairs identified (yes/no)	Chairs/co-chairs reporting COI, n/N (%)*†	Disclosure statement (yes/no)
G1	2023	AGA; ACG	Chronic idiopathic constipation	15	7 (46.7)	No	N/A	Yes
G2	2024	ACG	Helicobacter pylori	7	5 (71.4)	No	N/A	Yes
G3	2020	ACG	Irritable bowel syndrome	7	Not specified	No	N/A	Yes
G4	2022	AGA	Irritable bowel syndrome	6	Not specified	No	N/A	Yes
G5	2022	AGA	Irritable bowel syndrome	6	2 (33.3)	No	N/A	Yes
G6	2023	AASLD; IDSA	Hepatitis C	16	15 (93.8)	Yes	3/3 (100.0)	Yes
G7	2019	AASLD; IDSA	Hepatitis C	28	14 (50.0)	Yes	3/4 (75.0)	Yes
G8	2024	AASLD	MASLD	7	3 (42.9)	No	N/A	Yes
G9	2023	AASLD	NAFLD	8	6 (75.0)	No	N/A	Yes
G10	2019	AGA	Ulcerative colitis	6	Not specified	No	N/A	Yes
G11	2024	AGA	Ulcerative colitis	7	4 (57.1)	No	N/A	Yes
G12	2019	ACG	Ulcerative colitis	5	4 (80.0)	No	N/A	Yes
G13	2021	AGA	Crohn’s disease	7	3 (42.9)	No	N/A	Yes

^*COI status based solely on disclosures reported within the guideline manuscript, appendix, or supplementary materials. ‘Not specified’ indicates that a disclosure section was present but individual author-level conflicts were not itemised within the published materials.

^†'N/A’ indicates that no chair or co-chair role was explicitly designated in the guideline.

COI, conflict of interest; AGA, American Gastroenterological Association; ACG, American College of Gastroenterology; AASLD, American Association for the Study of Liver Diseases; IDSA, Infectious Diseases Society of America; MASLD, metabolic dysfunction–associated steatotic liver disease; NAFLD, non-alcoholic fatty liver disease.

All guidelines included a disclosure statement; however, 3 of 13 (23.1%) guidelines did not itemise individual author disclosures, limiting author-level concordance assessment for those guidelines (table 4). Among guidelines with itemised disclosures, the proportion of authors reporting at least one financial relationship ranged from 33.3% to 93.8% (table 4). Chairs or co-chairs were explicitly designated in only 2 of 13 guidelines (table 4). IOM Standard 1 (COI disclosure statement present) was met in all guidelines (table 5). IOM Standard 2a (chair or co-chair reporting no financial COI in the guideline disclosure statement, regardless of relevance to the guideline topic) applied to the two guidelines that explicitly designated chair or co-chair roles and was not met in either (table 5). IOM Standard 2b (majority of panel COI-free) was met in only 4 of 13 guidelines (30.8%) (table 5). Overall compliance with all IOM standards was observed in 4 of 13 guidelines (30.8%) (table 5).

Table 5. IOM conflict of interest compliance assessment by guideline.

Guideline ID	IOM standard 1: disclosure met (yes/no)*	IOM standard 2a: chair/co-chair COI-free (yes/no)†	IOM standard 2b: majority of panel COI-free (yes/no)*	Overall IOM compliance (yes/no)‡
G1	Yes	N/A	Yes	Yes
G2	Yes	N/A	No	No
G3	Yes	N/A	No	No
G4	Yes	N/A	No	No
G5	Yes	N/A	Yes	Yes
G6	Yes	No	No	No
G7	Yes	No	No	No
G8	Yes	N/A	Yes	Yes
G9	Yes	N/A	No	No
G10	Yes	N/A	No	No
G11	Yes	N/A	No	No
G12	Yes	N/A	No	No
G13	Yes	N/A	Yes	Yes

^*IOM compliance was assessed strictly using information explicitly reported within the guideline manuscript, appendix, or supplementary materials. When author-level disclosures were not itemised or when compliance with a specific IOM standard could not be definitively determined from published materials, the standard was coded as not met to avoid assumptions beyond the reported data.

^†'N/A’ indicates the standard was not applicable because a chair or co-chair role was not explicitly designated.

^‡Overall compliance required fulfilment of all applicable IOM standards.

COI, conflict of interest; IOM, Institute of Medicine.

Disclosure discordance between guideline-reported COI and relevant manufacturer payments varied substantially across guidelines (table 3; online supplemental tables S2 and S31). The highest discordance was observed in the 2020 American College of Gastroenterology IBS guideline (G3) and the 2024 American Gastroenterological Association UC guideline (G11), each with 85.7% of authors demonstrating discordant disclosures. These guidelines also had the highest prevalence of relevant manufacturer payments among authors. Across these two guidelines, 13 of 14 author appearances (92.9%) received relevant manufacturer payments. By contrast, among guidelines in which half or fewer authors had disclosure discordance, 48 of 110 author appearances (43.6%) received relevant manufacturer payments. In the 2024 living UC guideline (G11), all authors received relevant manufacturer payments despite relatively modest median payment amounts (US$1308.62), whereas the 2020 IBS guideline (G3) demonstrated both a high proportion of authors receiving relevant manufacturer payments (85.7%) and the highest median relevant payments (US$96 707.58).

Relevant manufacturer payments and disclosure discordance also varied by disease domain (table 3). Guidelines addressing IBD and IBS demonstrated higher exposure and discordance (author payment exposure 50%–100%; discordance 31.3%–85.7%), whereas guidelines addressing steatotic liver disease and Helicobacter pylori infection demonstrated lower exposure and discordance (author payment exposure 25%–33.3%; discordance 0%–16.7%) (table 3).

Institutional industry-funded research exposure was identified in all 13 guidelines during the COI window (online supplemental table S4), including guidelines with no author-level relevant manufacturer payments. A visual summary of the principal study findings is provided in online supplemental figure S1.

Discussion

In this cross-sectional analysis of 13 contemporary US gastroenterology and hepatology clinical practice guidelines published between 2019 and 2024, industry payments from manufacturers of guideline-recommended therapies to guideline authors were common and governance structures permitting transparent external evaluation of these relationships were inconsistent. Although all guidelines included some form of disclosure statement, author-level itemisation, leadership designation, and adherence to established IOM transparency standards varied substantially.^{1 4–6}

Nearly half of all authors (46% of unique authors) received payments relevant to guideline recommendations, including over half of authors in leadership roles. Most were general payments, particularly consulting and honoraria, and many exceed amounts (median payment of ~ US$9000 per author) that would be considered financially meaningful. Our findings are consistent with prior studies that have shown a high prevalence of financial COI among guideline authors,^10–13 but extend the existing literature by specifically evaluating payment from manufacturers whose products were directly recommended within the guideline itself. Under-reporting of relevant manufacturer relationships was identified across multiple guidelines, including among authors occupying formal leadership positions. Because guideline chairs exert a disproportionate influence over recommendation framing and evidence interpretation, transparent disclosure and externally auditable governance structures remain vital to maintaining public and professional trust in clinical practice guidelines. Although the presence of financial relationships alone does not establish inappropriate influence or biased recommendations, our findings suggest that current COI management policies fail to mitigate the risk of bias and more work is needed.

Despite longstanding IOM recommendations regarding COI disclosure and management published more than a decade ago, most contemporary guidelines in our cohort (9 of 13 guidelines) did not meet IOM standards. Further, many guidelines lacked sufficient transparency structures to allow for reliable external evaluation of author-level financial relationships, including those involving chairs and co-chairs.¹ Leadership roles were infrequently designated, several guidelines lacked itemised author-level disclosures, and disclosure discordance was common across multiple disease domains. Importantly, the presence of a disclosure section alone does not necessarily allow meaningful external auditability using publicly available information. Although some organisations referenced additional internal COI review processes or supplementary disclosure information available on request, such approaches do not eliminate the need for standardised and independently auditable reporting within the guideline document itself. Guideline organisations should adopt consistent disclosure frameworks that include explicit leadership designation, itemised author-level reporting, and clearly defined COI management procedures that can be easily viewed by the public.

We also identified variation in relevant manufacturer payments across disease domains and by authorship characteristics. For example, relevant payments were high in the IBD and IBS guidelines and low in the Helicobacter pylori infection guideline. Branded drugs comprise a large proportion of recommended treatments in the IBD and IBS guidelines and are comparatively lower in the Helicobacter pylori guideline, suggesting that the commercial structure of a therapeutic market may influence manufacturer relationships among guideline authors. Relevant manufacturer payments also clustered more heavily among authors contributing to multiple guidelines. Repeat authors exert a disproportionate influence, underscoring the importance of transparent disclosure practices and strict COI management policies in order to mitigate the risk of bias from these relationships.

Institutional research payments from relevant manufacturers to guideline authors were prevalent (10 of 13 guidelines). Although associated research payments include payments that are not personally received by a principal investigator, non-financial COI can still influence behaviour, and governance models focused exclusively on disclosure of personal payments may fail to capture this type of COI. Further work is needed to understand the full scope of COI related to institutional industry-funded research and the risk of bias associated with these relationships.

Some non-US guideline organisations, including National Institute for Health and Care Excellence, have published formalised approaches to COI governance and disclosure management, including standardised declaration processes, leadership restrictions, and explicit recusal procedures for conflicted panel members.^15–17 These models provide useful frameworks for improving transparency and auditability within US gastroenterology and hepatology guideline development. Future studies should evaluate whether similar patterns are present across other gastroenterology subspecialties and international guideline organisations. More research is needed to assess whether financial relationships are associated with recommendation-level outcomes, such as recommendation strength, evidence grading, or therapeutic selection. Assessing internal society COI management processes may help clarify how disclosures are operationalised during guideline development. Lastly, longitudinal evaluation of living guidelines may further clarify how evolving author panels, therapies, and financial relationships influence COI governance over time.

This study has several limitations. Our analysis relied on publicly available guideline documents and Open Payments data and could not assess internal society processes for managing COI or unpublished disclosure review procedures. Financial relationships involving sponsoring societies or organisations themselves were also not assessed. Second, manufacturer attribution was defined at the company level rather than the product level, which may overestimate relevance for companies with broad therapeutic portfolios. Third, payments were analysed descriptively, and the temporal relationship between payments and specific recommendation development could not be determined within the 36-month disclosure window.¹⁴ Institutional research payments were evaluated at the guideline level and could not be linked to specific recommendations or therapeutic programmes. Living guidelines may present additional challenges because panel composition, financial relationships, and recommended therapies can evolve over time, and a single disclosure window may not fully capture these dynamic relationships. In addition, Open Payments includes only US-based physicians and does not capture non-financial or intellectual conflicts. Finally, this study also did not evaluate the evidentiary quality of guideline recommendations and cannot determine whether financial relationships influenced guideline content.

Conclusion

Relevant industry payments to contemporary gastroenterology and hepatology guideline authors are prevalent and leadership designation and COI disclosure practices are inconsistent. Established COI governance standards, including standardised author-level disclosure reporting and explicit leadership designation, should be implemented more consistently to improve the transparency, auditability, and credibility of future clinical practice guidelines.^1–3

Data availability statement

Data sharing not applicable as no datasets generated and/or analysed for this study.