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Cohort profile: design and first results of the Dutch IBD Biobank: a prospective, nationwide biobank of patients with inflammatory bowel disease
  1. Lieke M Spekhorst1,2,
  2. Floris Imhann1,2,
  3. Eleonora AM Festen1,2,
  4. Ad A van Bodegraven3,
  5. Nanne KH de Boer3,
  6. Gerd Bouma3,
  7. Herma H Fidder4,
  8. Geert D’Haens5,
  9. Frank Hoentjen6,
  10. Daan W Hommes7,
  11. Dirk J de Jong6,
  12. Mark Löwenberg5,
  13. PW Jeroen Maljaars8,
  14. Andrea E van der Meulen-de Jong8,
  15. Bas Oldenburg4,
  16. Marieke J Pierik9,
  17. Cyriel Y Ponsioen5,
  18. Pieter C Stokkers10,
  19. Hein W Verspaget8,
  20. Marijn C Visschedijk1,2,
  21. C Janneke van der Woude11,
  22. Gerard Dijkstra1,
  23. Rinse K Weersma1
  24. on behalf of the Parelsnoer Institute (PSI) and the Dutch Initiative on Crohn and Colitis (ICC)
  1. 1Department of Gastroenterology and Hepatology, University of Groningen and Medical Center Groningen, Groningen, The Netherlands
  2. 2Department of Genetics, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands
  3. 3Department of Gastroenterology and Hepatology, VU University Medical Centre, Amsterdam, The Netherlands
  4. 4Department of Gastroenterology and Hepatology, University Medical Centre Utrecht, Utrecht, The Netherlands
  5. 5Department of Gastroenterology and Hepatology, Amsterdam Medical Centre, Amsterdam, The Netherlands
  6. 6Department of Gastroenterology and Hepatology, University Medical Centre St. Radboud, Nijmegen, The Netherlands
  7. 7UCLA Center for Inflammatory Bowel Diseases, Division of Digestive Diseases, David Geffen School of Medicine, University of California, California, Los Angeles, USA
  8. 8Department of Gastroenterology and Hepatology, Leiden University Medical Centre, Leiden, The Netherlands
  9. 9Department of Gastroenterology and Hepatology, University Medical Centre Maastricht, Maastricht, The Netherlands
  10. 10Department of Gastroenterology and Hepatology, St Lucas Andreas Ziekenhuis, Amsterdam, The Netherlands
  11. 11Department of Gastroenterology and Hepatology, Erasmus Medical Centre, Rotterdam, The Netherlands
  1. Correspondence to Dr Rinse K Weersma; r.k.weersma{at}


Purpose The Dutch IBD Biobank aims to facilitate the discovery of predictors for individual disease course and treatment response in patients with inflammatory bowel disease (IBD). In this paper, we aim to describe the establishment of the Dutch IBD Biobank, including the facilitators and barriers to establishment. Moreover, we aim to provide a complete overview of the content of the Dutch IBD Biobank.

Participants Since 2007, every patient with IBD treated in one of the eight Dutch university medical centres is asked to participate in the Dutch IBD Biobank in which 225 standardised IBD-related data items and biomaterials, such as serum, DNA, biopsies and a stool sample, are collected.

Findings to date As of June 2014, the Dutch IBD Biobank had enrolled 3388 patients with IBD: 2118 Crohn’s disease (62.5%), 1190 ulcerative colitis (35.1%), 74 IBD-unclassified (2.2%) and 6 IBD-indeterminate (0.2%). The inclusion of patients with IBD is ongoing. The quality of the biomaterials is good and serum, DNA and biopsies have been used in newly published studies.

Future plans The genotyping (750 000 genetic variants) of all participants of the Dutch IBD Biobank is currently ongoing, enabling more genetic research. In addition, all participants will start reporting disease activity and outcome measures using an online platform and mobile app.

  • gastroenterology
  • inflammatory bowel disease
  • ulcerative colitis
  • Crohn’s disease
  • biobank

This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:

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Strengths and limitations of this study

  • A major strength of the Dutch IBD Biobank is its prospective design.

  • Another strength is the participation of all eight university medical centres in the Netherlands.

  • The data records are complete and the biomaterials have successfully been used in several experiments.

  • A weakness is the selection bias, because all university medical centres in the Dutch IBD Biobank are tertiary referral centres.

  • A major challenge was the establishment of the local and central information technology infrastructure.


Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gut comprising Crohn’s disease (CD) and ulcerative colitis (UC). Of the 17 million inhabitants in the Netherlands, 39 000 individuals have been diagnosed with CD and 48 000 individuals with UC.1 Approximately 39 new individuals per 100 000 are newly diagnosed with IBD every year. This incidence rate continues to rise, posing an increasing burden on society.2 The clinical symptoms of IBD consist of diarrhoea, abdominal discomfort, weight loss, fatigue and rectal bleeding. However, these symptoms vary greatly both between individuals and in time. Some patients with IBD have a relatively mild disease course, requiring only limited therapeutic intervention, while others have a severe disease course with frequent flares requiring expensive medical and surgical interventions.

In recent years, many case–control studies have been performed to identify factors that can explain the onset of IBD. Genome-wide association studies (GWAS) have identified 200 genomic loci that are involved in the onset of IBD.3 Epidemiological studies have identified environmental risk factors including smoking, appendectomy, infections, antibiotics, diet and lifestyle (stress, lack of sleep and/or exercise) that could trigger the onset of IBD.4 Studies on the bacterial composition of the gut (the gut microbiota) have identified distinct microbial compositions associated with IBD.5 6 Unfortunately, these studies provide little insight into reasons for the heterogeneous clinical presentation and disease course of patients with IBD. As a consequence, limited progress has been made in translating basic science into personalised treatment. Predicting individual disease outcome and tailoring IBD treatment requires prospective patient data on disease activity, complications and treatment, as well as biomaterials and -omics data (genome, transcriptome and gut microbiome), in order to link biomarkers to disease. To this aim, the prospective Dutch IBD Biobank was created. A new national institute to facilitate the biobank and other national biobanks was founded by the Dutch Federation of University Medical Centres (NFU) in 2007 and called the Parelsnoer Institute (PSI).7 Gastroenterologists who specialised in treating patients with IBD in all eight Dutch university medical centres (UMC), together with a team of information architects and laboratory experts, built up the Dutch IBD Biobank.

The main objective of the biobank is to facilitate the discovery of predictors (both epidemiological risk factors and biomarkers) for individual disease course and treatment response, by:

  1. providing full clinical records of patients describing their individual disease course over a prolonged period of time;

  2. providing high-quality biomaterials;

  3. standardising patient data collection and questionnaires during outpatient clinic visits and thereby improving clinical care.

The aim of this paper is to inform the IBD research community about the existence of the Dutch IBD Biobank and to give an elaborate overview of the establishment process as well as the content.

Cohort description

Design, participating centres and the Dutch healthcare setting

The Dutch IBD Biobank is a prospective, nationwide biobank in which both data and biomaterials are collected. In the Netherlands, there are approximately 80 hospitals and 8 UMCs (tertiary referral centres), where patients with complex IBD are referred to. All eight Dutch UMCs participate in the Dutch IBD Biobank. The Dutch UMCs are: the Amsterdam Medical Centre in Amsterdam, the Erasmus Medical Centre in Rotterdam, the Leiden University Medical Centre in Leiden (LUMC), the Maastricht University Medical Centre in Maastricht (MUMC), the Radboud University Nijmegen Medical Centre in Nijmegen, the University Medical Center Groningen in Groningen (UMCG), the University Medical Centre Utrecht in Utrecht and the VU (Vrije Universiteit) University Medical Centre in Amsterdam. PSI and the Dutch IBD Biobank are part of the Biobanking and Biomolecular Resources Research Infrastructure of the Netherlands (BBMRI-NL). This is the Dutch national node of BBMRI-ERIC, the largest research infrastructure project in Europe.8

Standardised data collection: the information model

Gastroenterologists from each of the eight UMCs convened to design the information model based on literature review and clinical standards. A working group of gastroenterologists made a longlist of data items including a definition for each data item. This longlist was subsequently discussed during a meeting in 2006, where one or more representatives from each Dutch UMC were present. Data items and definitions were accepted, modified if deemed necessary, or rejected if deemed not part of the core data set. This process was repeated until consensus was reached. The Dutch IBD Biobank prospectively collects 225 standardised data items on various topics, including patient demographics, family history, diagnosis, disease activity, disease localisation, results of physical examinations, radiographic imaging results, laboratory and endoscopy results, previous and current treatment, as well as a wide array of disease and treatment complications. Validated questionnaires and scores, such as the Harvey-Bradshaw Index (HBI), the Simple Clinical Colitis Activity Index (SCCAI) and the Montreal classification are incorporated in the information model. This model contains both the IBD-related items as well as instructions on how to score these items. It has been shown that clinicians score subphenotypes of IBD similarly, with a good to excellent interobserver agreement.9 The information model is provided in English in online supplementary table 1 and can be downloaded in Dutch on the PSI website: The Dutch IBD Biobank information model is regularly updated. The latest version is based on the coding system called Detailed Clinical Models ( and is called PRISMA (Parelsnoer Repository for Information Specification, Modelling, and Architecture).

Supplementary table 1

Local databases and infrastructure

Each UMC has implemented the information model and collects and stores their patient information locally. As stated by the NFU, research data should be collected and registered directly at the source, that is, during the patient visit. Therefore, the data collection process should be incorporated into the clinical care structure.10 This approach has been gradually implemented in each UMC depending on the capacities of their electronic health record (EHR) system. At the moment, each UMC has a procedure to extract, transform and upload pseudonymised information of participants to the PSI central database (figure 1). The UMCs are in different stages of having implemented the ‘at the source’ approach. In some UMCs it is already fully implemented, whereas in other UMCs this process has not yet begun. The first visit is prepared by a trained research nurse and since most of the 225 data items do not change during every visit, for example, family history, medical doctors usually only need to register a subset of items during visits.

Figure 1

Overview of the data and biomaterial infrastructure of the Dutch IBD Biobank, built by the Parelsnoer Institute in collaboration with all eight university medical centres (UMC) in the Netherlands. IBD, inflammatory bowel disease; ID, identifier.

Central Database and Central Data Infrastructure

Pseudonymised information about study participants is stored in the Central Database, managed by the Advanced Data Management (ADM) section of the Department of Medical Statistics and BioInformatics of the LUMC.

The software ProMISe, a web-based relational database management system for the design, maintenance and use of clinical data management, is used to store the Central Database. ( Researchers can access data in the Central Database following approval of their research proposal in secure web-based environment. Together, the Central Database and the web application form the Central Data Infrastructure (figure 1).7

Data upload and pseudonymisation

In each UMC, data are automatically uploaded from the Local Database to the Central Database at least once a month. During the upload process, pseudoanymisation is performed by a trusted third party (TTP). Only the TTP has access to key containing both the local identifiers and the Dutch IBD Biobank identifier. Prior to the upload, data validation is performed locally on a set of essential data items. If necessary, corrections are made locally and subsequently included in the next upload. A full audit trail is in place for the entire process.

Privacy and information security audits

ADM, the Central Database and the Central Data Infrastructure software are audited according to Dutch NEN751011 international ISO 27.00112 information security guidelines. ADM is audited twice per year while its software is periodically audited by Lloyds Register Quality Assurance, a certified independent auditor.

Biomaterial collection

In addition to the data items, biomaterials are collected from all patients with IBD: including DNA, serum, faeces, mucosal biopsies and resection specimens when surgical procedures were required. Laboratory experts of all eight university hospitals convened to create uniform biomaterial collection and processing protocols. The biomaterials are stored in one of the eight local biobanks (figure 1). The biomaterial identifiers are uploaded to the Central Database and linked to the clinical data. Neither the local biomaterial identifiers nor the stickers on the biomaterial vials contain identifiable patient information. During the upload process, a unique additional biomaterial identifier is added to the local biomaterial identifier in case multiple UMCs have a biomaterial with the same identifier. When a research project is approved, all eight local biobanks will send the required biomaterials to the researcher while the biomaterial identifiers linked to the clinical data can be downloaded using the secure web portal of the Central Infrastructure. If a biomaterial sample does not meet the required standards, the sample will be disposed. A brief summary of the biomaterial protocol is provided in table 1.7 The entire biomaterial protocols can be downloaded from, but are only available in Dutch.

Table 1

Sample collection7


The Dutch IBD Biobank has two national coordinators and an assistant coordinator, who manage updates of the information model and the delivery of data and biomaterial to researchers (figure 1).

Informed consent

All patients with IBD who are treated in the Dutch UMCs are asked to participate in the Dutch IBD Biobank by their gastroenterologist during a visit to the outpatient department of their UMC. If they are willing to participate, they are asked to sign an informed consent form (English translation in online supplementary document 1). Patients who choose to participate may revoke their consent at any point, after which their data and biomaterials will be removed from the Dutch IBD Biobank. Data and biomaterials that have already been sent to a researcher cannot be revoked, which is clearly stated in the patient informed consent form.

Patient enrolment

Patient enrolment started in January 2007 and is ongoing (table 2).

Table 2

Demographic characteristics of patients with IBD after the first data download on 17 July 2014, per university medical centre

Not all patients were asked to join at once, but they were asked in batches so gastroenterologist and research nurses could manage the initial data registration.

Every patient with IBD enrolled has a proven IBD diagnosis according to the Lennard-Jones criteria.13 Diagnosis is confirmed by endoscopy, radiology and/or histology.


To create an overview of the content of the biobank, the characteristics of the patients were assessed. The following clinical and demographic items reported in this study are registered at the time of inclusion in the Dutch IBD Biobank and are referred to as baseline: first diagnosis, disease localisation, smoking status, employment status, gender, ethnicity, presence of a stoma or pouch, disease activity (modified HBI and modified SCCAI score) and date of birth. Disease localisation is scored according to the Montreal classification, which describes the maximum disease extent during entire disease course, and is registered at baseline. Disease localisation has to be confirmed by radiology, endoscopy or histology assessment. The items dysplasia, bowel cancer, family history of IBD, current diagnosis and medication use described in this study were registered during the last follow-up visit before the data download in July 2014. Items describing disease behaviour, surgery, appendectomy, extraintestinal manifestations (EIM) and complications were registered over the entire disease course up to baseline. The definitions baseline, last follow-up visit before the data download and over the entire disease course up to baseline are graphically explained in online supplementary figure 1.

Statistical analyses

All descriptive statistics and statistical analyses are performed using Stata software V.13.1 ( Continuous variables are expressed as medians and IQRs 25 and 75. Qualitative variables are presented as counts and frequencies. We compared outcomes between patients with CD and UC. Qualitative variables were analysed using the Pearson’s Χ2 test. Quantitative variables were analysed using the Mann-Whitney U test. We performed a multivariate analysis of the effect of smoking on different outcomes in all patients with IBD. We corrected for covariates with p<0.20 in the univariate analyses (age, gender, diagnosis, disease duration and prior anti-tumour necrosis factor use). The statistical models were built using backward selection: covariates that were not statistically significantly influencing the outcome variable (p>0.05) were removed from the model. We then applied the same strategy to patients with CD and UC separately to correct for disease activity. A p Value <0.05 was considered statistically significant.


Clinical and demographical follow-up data are collected at every visit to an outpatient department. Usually, patients with IBD in the Netherlands are seen by a gastroenterologist twice a year. This is standard clinical care following treatment protocols used in every UMC. The disease course is heterogeneous, as a consequence, data available on follow-up can be extensive for one patient but more limited for another. If requested by the gastroenterologist, a blood sample is taken. Furthermore, if required, intestinal mucosal biopsies are collected during endoscopy and resection specimens are obtained during surgery.

Findings to date

Consent rate and differences between participants and non-participants

We first assessed possible differences between patients with IBD willing to participate in the Dutch IBD Biobank and patients with IBD who did not want to participate. To do so, a subset at one UMC (UMCG) was downloaded and analysed. This subset was used because privacy guidelines do not allow data of participants not wishing to take part to be uploaded to the PSI central database. On 17 July 2014, after the first data download, 786 patients were asked to participate in the UMCG. Of these, 742 patients with IBD gave their informed consent while 44 patients with IBD declined to participate. The consent rate was 93.4%. Table 3 provides an overview of the characteristics of those who consented to participate and those who did not. Of the 742 patients who consented, 625 were used in the analysis of the 2014 data because they met the selection criteria (clear IBD diagnosis, known date of birth and gender, informed consent and isolated DNA available including a biomaterial identifier). The characteristics of the consenting and non-consenting patients were similar. Only disease location according to the Montreal classification was statistically significantly different between these two groups (p=0.037, Χ2 test).

Table 3

Baseline characteristics of the responders and non-responders recruited through the University Medical Center Groningen on 17 July 2014

The characteristics of the Dutch patients with IBD in UMCs

A download of data on 17 July 2014 was analysed to explore the demographic and clinical characteristics of the cohort recruited to that date. It included 3388 patients with IBD: 2118 CD (62.5%), 1190 UC (35.1%), 74 IBD-unclassified (2.2%) and 6 IBD-indeterminate (0.2%). The median age of patients with IBD at inclusion was 42 years old (IQR 32–54 years) (tables 4-6). In all, 93% of patients are of Central European Caucasian descent and the other 7% are of African, Hindustani, Moroccan, Turkish, Asian, Jewish, other western, other non-western or mixed descent. Smoking status at the time of first IBD diagnosis was registered for 3021 patients with IBD (89%), and more patients with CD smoked compared with patients with UC (44% CD, 18% UC, p<0.001). Patients with UC were more likely to have quit smoking in the 6 months prior to the first IBD diagnosis (1.0% CD, 4% UC, p<0.001). Ileocolonic disease in patients with CD (46%) (figure 2) and extensive colitis (E3) in patients with UC (56%) (figure 3) are more common in our cohort than in other studies (figures 4 and 5).14–18  The high number of patients with extensive disease in our cohort can be explained by a selection bias (tertiary referral centres). The disease locations in CD were similar in men and women (figure 6).

Table 4

Demographic characteristics of patients with inflammatory bowel disease in the Dutch IBD Biobank cohort on 17 July 2014

Table 5

Clinical characteristics, extraintestinal manifestations and complications in patients with inflammatory bowel disease in the Parelsnoer Institute cohort

Table 6

Malignancies, surgery and medication use of patients with inflammatory bowel disease in the Parelsnoer Institute cohort

Figure 2

Disease localisation in patients with Crohn’s disease in the Dutch IBD Biobank according to the Montreal classification. GI, gastrointestinal.

Figure 3

Disease localisation in patients with ulcerative colitis in the Dutch IBD Biobank according to the Montreal classification.

Figure 4

Date of Crohn’s disease diagnosis and of disease location (L) according to the Montreal classification. L1, ileal; L2, colonic; L3, ileocolonic.

Figure 5

Date of ulcerative colitis diagnosis and of disease extent (E) according to the Montreal classification. E1, proctitis; E2, left-sided colitis; E3, pancolitis.

Figure 6

Disease location (L) according to the Montreal classification stratified by sex in patients with Crohn’s disease (CD). L1, ileal; L2, colonic; L3, ileocolonic.

Moreover, the most extensive disease during the entire disease duration (Montreal L (disease location) in patients with CD and Montreal E (disease extent) in patients with UC) is well documented in the Dutch IBD Biobank, while other studies often only report disease extent at the time of diagnosis (median disease duration in the Dutch IBD Biobank is 12 years). EIMs are more common in patients with CD than in patients with UC, which we corroborated in the Dutch IBD Biobank data (figure 7).19–21 We found that patients with UC who smoked more often suffered from ocular manifestations and arthropathy than those who did not smoke, matching previous findings.22 23 An increased risk of EIM in patients with CD who smoked has previously been reported,24 but we could not confirm this result in our cohort.

Figure 7

Extraintestinal manifestations and complications of patients with inflammatory bowel disease (IBD) in the Dutch IBD Biobank.

Genetic predictor of a fibrostenotic or inflammatory disease course in CD

The availability of genomic data and detailed clinical data in the Dutch IBD Biobank enabled a GWAS that aimed to find genetic predictors for recurrent fibrostenotic disease in patients with CD, by comparing the extremes of the clinical spectrum: (1) patients with CD with a mild disease course defined by inflammation without any signs of stricturing or penetrating disease during the last 5 years, versus (2) patients with CD who underwent ileocaecal resection due to confirmed intestinal strictures at least twice. We identified a genetic variant in the WWOX gene that regulates fibrosis through the SMAD pathway. The WWOX gene could therefore be an important signalling modulator involved in fibrostenotic CD (Resubmitted to the Journal of Crohn’s and Colitis).

Previously published finding: Rare variants in MUC2 are associated with UC in the Dutch population. A subsequent study aimed to identify rare genetic variants with a large effect on UC susceptibility. Pooled resequencing of 122 genes in UC susceptibility loci in 1021 Dutch UC cases and 1166 Dutch controls revealed that rare variants in the MUC2 gene were associated with increased UC susceptibility (gene-based analysis with SKAT-O, nine variants in the MUC2 gene: p value of 9.2×10−5; threshold p=0.0011 after Bonferroni correction). Interestingly, this association appeared to be population specific for the Netherlands.25 Using the same approach and samples, a protein truncating variant in RNF186 that protects against UC was also identified.26

Associations between genetic variants and subphenotypes of IBD

The Dutch IBD Biobank participated in a large study where the clinical characteristics of patients with IBD were associated to genetic variants. The discovery of genetic variants associated with specific disease location and disease behaviour was published in the Lancet.27

GWAS and sequencing studies investigating the IBD diagnosis using DNA collections that were integrated in the Dutch IBD Biobank

For 1904 participants of the Dutch IBD Biobank genotype data are available consisting of ~200 000 single nucleotide polymorphisms (SNP) obtained using the Immunochip, an Illumina genotyping array focused on immune-mediated diseases. These genotype data were used in landmark genetic studies published in Nature and Nature Genetics investigating IBD pathogenesis.3 28–30 These studies led to the discovery of 200 genetic loci associated with IBD, explaining 21.3% of the onset of IBD.

Discussion: strengths and weaknesses of the Dutch IBD Biobank


A major strength of the Dutch IBD Biobank is its prospective design and extensive uniform information model comprising 225 data items, and the participation of all eight UMCs in the Netherlands. In addition, the biomaterials such as serum, DNA and a stool sample are collected at baseline, and, if available, biopsies from endoscopy and resection tissue are collected during follow-up, allowing the integration of subphenotypes enabling biomarker discovery research.

Since IBD is a chronic disease that requires lifelong treatment, patients treated in tertiary centres are rarely referred back to a general or local hospital and therefore loss to follow-up is uncommon.

Barriers to establishment and limitations

Setting up the Dutch IBD Biobank required a tremendous effort and there were many barriers to establishment. While some of these barriers were overcome, some limitations of the Dutch IBD Biobank remain. After a large initial grant provided by the Dutch government to the Netherlands Federation of University Medical Centres facilitating the establishment of the Dutch IBD Biobank and seven similar biobanks ended in 2011, the Dutch UMCs had to fund the continuation of the Dutch IBD Biobank themselves, meaning a reduction of staff that assisted in patient inclusion in some centres. As a consequence, the enrolment of patients has slowed down in these centres.

A major challenge was the establishment of the information technology (IT) infrastructure. In all UMCs, the local EHRs needed to be adapted so that the necessary information could be extracted. The gradual process of implementing data collection ‘at the source’ during the patient visit, and the renewal of EHRs in several hospitals means that adaptations to the local IT infrastructure continue to be necessary. Similar projects should be aware that the investments in the IT infrastructure will be ongoing after the establishment, and make sure they anticipate that continuous funding is required.

Data completeness, data similarity, data validation, quality control and feedback

A large majority of the data items were completely scored as can be seen in tables 3-6. However, the different collection approaches by different UMCs sometimes lead to small differences in the clinical data, as some items were scored differently. Prior to completing this study, the authors reviewed all data and reported all inconsistencies to the national coordinators and to all UMCs. Several gastroenterologists, research nurses and IT departments improved the local data and a new upload to the Central Database was performed. Initially, very strict data validation steps were included in the Central Database software. However, these validation steps were too strict, and, because clinical patient records are often imperfect, very few patient records could be uploaded to the Central Database. After being aware of this problem, all data validation steps were removed from the Central Database software. Unfortunately, the lack of data validation steps led to errors in the data. Now, a small set of data validation protocols is in place. We recommend similar initiatives to start with simple data validation protocols and gradually expand these as the data quality and collection protocols improve.

Selection bias

Because all tertiary referral centres in the Netherlands participate in the Dutch IBD Biobank, the cohort will contain a large fraction of patients with IBD with a more severe disease course. This IBD cohort is not therefore suitable for studies that require a population-based cohort, for example, studies on the incidence and prevalence of IBD manifestations.


IBD researchers of the Dutch UMCs can access the Dutch IBD Biobank data and biomaterials after their research proposal has been approved by the Scientific Committee of the Dutch IBD Biobank. Other researchers can use the data and biomaterials of the Dutch IBD Biobank, but have to establish a cooperation with one or more Dutch UMCs.

Research proposal and application process

Research proposals can be submitted to the Scientific Committee and the Institutional Review Board. Proposals are judged against the following criteria:

  1. It is reasonably plausible that the proposed research could lead to new insights.

  2. The aims in the research proposal can be met using the proposed research methodology.

  3. The proposed research is in concordance with the patient informed consent.

  4. The proposed research will be conducted by people in institutes and facilities that are skilled and able to conduct the research.

  5. The research proposal does not request more data and biomaterials than necessary.

  6. The research proposal meets reasonable standards.

  7. The proposed research does not unacceptably conflict or overlap with other research proposals.

After the Scientific Committee has approved a research proposal, the data manager will provide the pseudonymised research data in the web-based environment, and will facilitate the biomaterial delivery to the researcher. Applicants do not have to pay a fee.

The Dutch IBD Biobank can be contacted via email: More information can also be found on the PSI website: The Dutch IBD Biobank aims to cooperate with international IBD research groups. The information model and the list of biomaterials are publicly available and can be downloaded from the PSI website. The Dutch IBD Biobank encourages other biobanks to use the same information model and biomaterial collection standards to enable larger international studies on IBD and we encourage similar initiatives to contact us in an early stage.

Future developments

Genotyping the entire Dutch IBD Biobank

All DNA samples are in the process of being genotyped with a newly developed genome-wide genotyping array from Illumina, containing 750 000 SNPs. These data will be leveraged by imputation against whole genome sequence data of 700 Dutch individuals studied in the Genome of the Netherlands project.31 The availability of the genotype data will enable more genetic studies.

Web-based data access for researchers

The Dutch IBD Biobank is working on a multiomics data sharing portal called the Molgenis Research IBD Portal, based on Molgenis software.32 This portal will make summary level statistics publicly available.

Mobile app for patients

The web-based follow-up of Patient-Reported Outcome Measurements including clinical disease activity scores is another project that the Dutch IBD Biobank is implementing. Patients will regularly fill in online questionnaires on disease activity, treatment response, quality of life and quality of care. Several UMCs are using the app My IBD Coach: The use of this app for IBD eHealth was extensively tested in a trial led by the MUMC, the Netherlands, where it was proven effective in reducing the number of hospital admissions.33


The Dutch UMCs have together created a biobank containing data and biomaterials of more than 3000 patients with IBD. The creation of the Dutch IBD Biobank took a very large multicentre multiyear effort, and new projects continue to improve the infrastructure and data collection. The main objective of the biobank is to facilitate the biomarker discovery. By now, studies using the Dutch IBD Biobank have led to the discovery a genetic predictor of a more severe disease course in patients with CD, showing that combining -omics data with prospectively collected clinical records can lead to useful results. Whether the standardising of patient data collection and during the patient visits and questionnaires online improves the clinical care of patients with IBD in the Netherlands is not yet known, but studies investigating the use of online disease activity scores and early detection of IBD exacerbations in the Netherlands are showing a reduction in hospitalisations.33 We encourage researchers who want to establish similar biobanks to contact us, and to take our important recommendations, including the continuous IT funding, and the step-by-step implementation of data quality measures described in the discussion, into account.

supplementary document 1

supplementary figure 1


We would like to thank all the patients who participate in the Dutch IBD Biobank; all the nurses who have participated in data entry; all the gastroenterologists who have aided in patient enrolment; Florien Toxopeus, Judith Manniën; Tessa Ledderhof; the Board of the Parelsnoer Institute; and Promise/ADM.


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  • Contributors AAvB, DWH, DJdJ, BO, MJP, PCS, CJvdW and GD founded and designed the Dutch IBD Biobank together with the Parelsnoer Institute (PSI) and the Initiative on Crohn and Colitis (ICC). The Parelsnoer Institute (PSI) provided the Information Technology (IT) infrastructure. The Initiative on Crohn and Colitis (ICC) provided the platform to discuss the updates and the progress of the Dutch IBD Biobank. EAMF, AAvB, NKHdB, GB, HHF, GdH, FH, DWH, DJdJ, ML, PWJM, AEvdMdJ, BO, MJP, CYP, PCS, HWV, CJvdW, GD, RKW and the PSI created, updated and extended the Dutch IBD Biobank information model. EAMF, AAvB, NKHdB, GB, HHF, GdH, FH, DWH, DJdJ, ML, PWJM, AEvdMdJ, BO, MJP, CYP, PCS, HWV, CJvdW, GD and RKW enrolled the patients with IBD, and gathered and entered the patient data that were uploaded in the Dutch IBD Biobank. FI, MCV, EAMF, GD and RKW applied for the first data download. FI, RKW and the PSI prepared the first data download. FI downloaded the data from the Central Database of the Dutch IBD Biobank. FI and LMS performed the data quality control. LMS prepared the data. LMS and EAMF performed the statistical analysis. FI and LMS wrote the manuscript. FI, LMS, MCV, EAMF, AAvB, NKHdB, GB, HHF, GdH, FH, DWH, DJdJ, ML, PWJM, AEvdMdJ, BO, MJP, CYP, PCS, HWV, CJvdW, GD, RKW, the PSI and the ICC critically assessed the manuscript and approved the final version.

  • Funding This nationwide PSI project is funded by the Netherlands Federation of University Medical Centres and it received initial funding from the Dutch government (from 2007 to 2011). PSI currently facilitates the uniform nationwide collection of information and biomaterials for 13 other diseases. This work is supported by the Netherlands Organisation for Scientific Research (NWO) (016.136.308 to RKW and 92.003.577 to MCV) and the Dutch Digestive Foundation (CDG 14-04 to EAMF).

  • Competing interests FI reports personal fees for speaking from AbbVie. AAvB reports personal fees for consultation or speaking from AbbVie, Ferring, MSD, Takeda, Tramedico and VIFOR, he is member of the Committee on Drugs of the Dutch Society for Gastroenterology (NVMDL). RKW reports unrestricted research grants from Ferring and Tramedico, and personal fees during the conduct of the study from Abbott but outside the submitted work. AEvdMdJ reports unrestricted research grants from Takeda and Abbott, and personal fees during the conduct of the study from Abbott, Takeda and Tramedico outside the submitted work. NKHdB reports unrestricted research grant from FALK outside the submitted work, personal fees for consultation or speaking from AbbVie and Teva Pharma, and he is a member of the Advisory Board of MSD.

  • Ethics approval Medisch ethische toetsingscommissie (METc) (IRB).

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data sharing statement Researchers can access the Dutch IBD Biobank data and biomaterials after their research proposal has been approved by an independent scientific committee. The data manager will then provide the pseudonymised research data in a secure, web-based environment, which is only accessible for the researcher. The Dutch IBD Biobank has two national coordinators and an assistant coordinator, who together manage the updates of the information model as well as data and biomaterial delivery to researchers (figure 1). The Dutch IBD Biobank can be contacted via email: More information can also be found on the PSI website: . The Dutch IBD Biobank aims to cooperate with international IBD research groups.