Veilig gebruik van contrastmiddelen

Initiatief: NVvR Aantal modules: 48

Veilig gebruik van contrastmiddelen bij patiënten met Mastocytose

Uitgangsvraag

Welke strategieën zijn effectief om hypersensitiviteitsreacties en anafylactische shock te voorkomen bij patiënten met systemische mastocytose na contrastmiddel(CM)-toediening?

Aanbeveling

Onthoud patiënten met systemische mastocytose niet van beeldvorming met een jodiumhoudend of gadoliniumhoudend CM.

 

Aanbevelingen bij toedienen van contrastmiddelen bij patiënten met systemische mastocytose:

  • Continueer antiallergische onderhoudsmedicatie (v.b. H1/H2-antihistamine)
  • Wees alert om te reageren op een mogelijke hypersensitiviteitsreactie
  • Observeer de patiënt ≥ 30 min met behoud van intraveneuze toegang
  • Na een allergische reactie, verwijs indien nodig naar een allergoloog

Overwegingen

Pros and cons of the intervention and quality of the evidence

Clonal mast cell disorders are characterized by the uncontrolled expansion and accumulation of mast cells in one or multiple organs. The term cutaneous mastocytosis is reserved for patients with aberrant mast cell infiltration limited to the skin. Involvement of bone marrow with or without other affected organs (including skin, gastrointestinal tract) leads to the diagnosis of systemic mastocytosis (SM). Mast cells are proinflammatory innate immune cells that can be activated by various stimuli, including allergens, microbes, viruses, and toxins. Upon activation, mast cells degranulate and thereby release various proinflammatory substances and lipid mediators, including tryptase and histamine. These mast cell-derived mediators lead to allergic symptoms and, in case of severe mast cell degranulation, may induce anaphylactic shock. Since patients with mastocytosis have increased numbers of mast cells and the activation threshold for these mast cells is lower due to mutations in their constitutively expressed KIT receptor, patients with systemic mastocytosis are at increased risk of anaphylaxis.

 

Besides the previously mentioned stimuli, there are several drugs and substances with an (theoretically) increased risk for mast cell degranulation. Potential elicitors are NSAIDs, general anaesthesia, and iodine-based contrast media (ICM); gadolinium-based contrast agents (GBCA) do not impose an increased (theoretical) risk. Hence, they were avoided as much as possible in systemic mastocytosis, although this practice is gradually changing. If given, these drugs and substances are administered cautiously and mostly with concomitant use of anti-allergic premedication, consisting of antihistamines and corticosteroids. However, since the actual clinical risk has seldom been studied systematically under real world conditions due to practical and ethical concerns, it is to date unclear how often and relevant drug-induced mast cell degranulation are for this patient category. Moreover, recent studies suggested that the risk of drug-induced anaphylaxis has been overestimated. For example, a double-blind placebo-controlled challenge with acetylsalicylic acid in patients with mastocytosis (n=50) elicited a mild hypersensitivity reaction in only one subject (Hermans, 2018).

 

One narrative review reported on the management of invasive procedures in mastocytosis including administration of contrast media (Hermans, 2017). The review did not represent a systematic literature search and did not describe the search methodology and could therefore not be included in the literature analysis. However, Hermans (2017) provided an overview of the risk of adverse reactions including anaphylaxis in patients with mastocytosis after contrast media administration. In addition, the review reported on premedication.

 

Hermans (2017) reported on four cohort studies among 457 adults with systemic mastocytosis who received contrast media (Brockow, 2008; González de Olano, 2007; Gülen, 2016; Hermans, 2016). Serious radiocontrast-related hypersensitivity was reported in 3/457 patients (0.65%), including development of anaphylaxis in one patient (0.22%) (Hermans, 2017). The number of cases in which premedication was used was not described. The number of serious adverse reactions in the general population to intravenous contrast administration was reported 0.5 to 3% for mild immediate reactions and 0.01 to 0.04% for serious adverse events (Andreucci, 2014; Thong, 2011). Hermans (2017) concludes there is no rationale for avoidance of contrast media in patients with mastocytosis, although some patients can be at increased risk for developing anaphylaxis. This applies particularly to patients with previous mast cell mediator-related symptoms during procedure, previous history of anaphylaxis (regardless of trigger), atopic background, use of b-blockers, ACE inhibitors or NSAIDs or severe mastocyte infiltration of the skin. Not only drugs, but also physical stimuli (temperature change, exercise, strong odours, pressure, friction) and emotional stress could potentially evoke non-IgE-mediated mechanisms that might cause mast cell degranulation. It is recommended to consider a patient-tailored risk assessment to assess which patients are indicated for premedication (Hermans, 2017).

 

A similar systematic literature search on the safety of contrast media was conducted in the soon to be published Dutch FMS guideline on mastocytosis 2022, which also did not yield any comparative studies on this subject. In that guideline it is cautiously suggested that iodinated contrast media can be safely applied in the majority of mastocytosis patients (Quality of evidence N/A; Hermans 2017). As a result, it is recommended to develop a personalized management plan for each mastocytosis patient after the diagnosis is made (FMS richtlijn Mastocytose, 2022).

 

Finally, Schwaab, et al. (2022) recently reported a retrospective analysis of 162 patients with indolent or advanced mastocytosis. Four of them (2.5%) reported a previous hypersensitivity reaction to iodinated contrast media. Hundred forty-eight (91%) of those patients underwent additional imaging, including 80 CT in 56 patients and 252 MRI in 127 patients. In 35 (24%) patients both types of scans were performed. Imaging without application of contrast media was obtained in 14 (9%) patients (CT, n=7; MRI, n=17). Daily anti-mediator therapy, including H1/H2 antihistamines and/or low dose prednisolone was continued. Additional prophylactic premedication (H1- and H2 antihistamine and 50mg methylprednisolone 30-60 minutes prior to the scan) was applied prior to 6 scans; 326/332 (98%) of the scans were performed without additional premedication. No contrast-mediated hypersensitivity reactions occurred. The authors conclude that in the absence of a previous contrast mediated hypersensitivity reaction, use of premedication prior to contrast enhanced imaging may be dispensable. Systemic mastocytosis patients represent a heterogeneous group of patients and as a result, values and preferences of both patients and physicians may vary widely. Whether or not to use premedication may cause anxiety or medicalization depending on the patient’s perspective.

For patients that have been diagnosed with systemic mastocytosis for a long time and have had uneventful iodinated contrast media administration under premedication (without premedication-related side effects), the adaptation of this protocol may cause unwarranted anxiety. In contrast, a newly diagnosed mastocytosis patient with no history of anaphylaxis may experience premedication as unnecessary medicalization, particularly if the patient has experienced side effects with these drugs in the past.

 

Costs

The direct costs of applying anti-allergic premedication with prednisolone and/or antihistamines are negligible, as the price of these drugs is very low. Therefore, one should consider the potential indirect costs of additional logistic procedures, as well as the potential adverse effects. These are low for antihistamines (mostly drowsiness) but occur for prednisolone, particularly in weakened patients and upon repetitive exposure.

Side effects include:

  • Risk of glucose dysregulation, particularly in patients with diabetes.
  • Risk of osteoporosis, particularly upon repetitive exposure.
  • Risk of immune suppression, particularly upon repetitive exposure.
  • Risk of temporary cognitive effects such as delirium, particularly in weakened patients. In severe cases, these side-effects may lead to hospitalization.

On the other hand, omitting premedication may potentially increase the risk of anaphylaxis, which will probably result in hospitalization with the associated costs. Therefore, premedication should be recommended in high-risk patients, i.e., patients with previous mast cell mediator-related symptoms during medical procedures, history of anaphylaxis (regardless of trigger), atopic background, use of b-blockers, ACE inhibitors or NSAIDs or severe mastocyte infiltration of the skin.

 

Acceptability, feasibility, and implementation

Based on the abovementioned arguments, it is not feasible to make one standard recommendation for the entire group of systemic mastocytosis patients. Recommending premedication in all patients is not indicated as it would lead to unnecessary anxiety, medicalization, side effects and associated costs in a selection of patients. Complete discourage of premedication however may lead to increased risk of anaphylaxis in a selection of patients. The treating physician should perform this risk assessment.

 

Recommendations 

It is important not to withhold iodinated contrast media from patients with systemic mastocytosis in case administration is necessary for optimal imaging. Despite the probably slightly increased risk of anaphylaxis (0.22% in mastocytosis versus the reported 0.01 to 0.04% for serious adverse events in the general population), the benefits of the imaging procedure should outweigh this small risk.

 

Do not withhold iodine-based contrast media or gadolinium-based contrast agents in patients with systemic mastocytosis.

 

Since there is no convincing evidence that use of anti-allergic premedication is beneficial for systemic mastocytosis patients prior to iodinated contrast administration, there is in general no need to apply this. However, systemic mastocytosis remains a heterogeneous disease with varying clinical symptoms and patients may suffer from comorbidities that should be considered. As a result, it is recommended that their treating physician with knowledge of both the disease and this specific patient should assess whether premedication should be employed. Patient with previous anaphylaxis, extensive skin involvement, use of ß-blockers, ACE inhibitors or NSAIDs may be at increased risk of developing anaphylaxis and additional premedication could be considered. Many mastocytosis patients already use H1- antihistamines (up to 4x the recommended daily dose) as part of their regular medication and these drugs should be continued. Preferably, the decision is shared by the patient and the physician and made timely before the patient needs iodine-based contrast media. The recommendation should be clearly reported in the electronic patient records. Comparable to other patient populations, it is possible that systemic mastocytosis patients develop an IgE-mediated allergy for a specific type of contrast. Therefore, in case a hypersensitivity reaction occurs, patients should be referred to a drug allergy specialist for further analysis.

 

Recommendation for administration of contrast media in patients with systemic mastocytosis:

  • Continue maintenance anti- allergic medication (e.g., H1-/H2-antihistamines).
  • Be vigilant to react to a possible hypersensitivity reaction.
  • Observe the patient ≥ 30 min with IV in place.
  • In case of an allergic reaction, refer to a drug allergy specialist.

 

Onderbouwing

It is unclear whether iodinated contrast media can cause hypersensitivity reactions in patients with systemic mastocytosis and whether prevention strategies should be employed.

No studies could be included in the literature analysis. Therefore, no systematic literature analysis could be performed.

A systematic review of the literature was performed to answer the following question: what is the efficacy of a preventive strategy with prednisone and/or antihistamines next to contrast administration compared to contrast administration without additional preventive strategy on the risk of developing anaphylactic shock, (drug) hypersensitivity reaction, anaphylactic allergic reaction in patients with systemic mastocytosis?

 

P (Patients): Patients with systemic mastocytosis and indication for examination with iodine-based contrast media.

I (Intervention): Contrast media administration with prednisone and/or antihistamine premedication.

C (Comparison): Contrast media administration without additional premedication or other preventive strategies.

O (Outcomes): Anaphylactic shock, (drug) hypersensitivity reaction, anaphylaxis, allergic reaction.

 

Relevant outcome measures

 

The guideline development group considered anaphylactic shock and anaphylaxis as critical outcome measures for decision making; and (drug) hypersensitivity reaction and allergic reaction as an important outcome measure for decision making. A priori, the working group did not define the outcome measures listed above but used the definitions used in the studies.

 

Search and select (Methods)

The databases Medline (via OVID) and Embase (via Embase.com) were searched with relevant search terms until March 5th, 2021. The detailed search strategy is depicted under the tab Methods. The systematic literature search resulted in twenty-one hits. Studies were selected based on the following criteria: (1) patients with systemic mastocytosis and an indication for examination with iodinated contrast media (2) comparing the adverse effects of contrast administration with prednisone and/or antihistamines administration with contrast administration without additional preventive strategy and (3) investigating one of the previously described outcomes. Five studies were initially selected based on title and abstract screening. After reading the full text, no studies could be included.

  1. Andreucci M, Solomon R, Tasanarong A. Side effects of radiographic contrast media: pathogenesis, risk factors, and prevention. Biomed Res Int. 2014; 2014: 741018.
  2. Brockow K, Jofer C, Behrendt H, Ring J. Anaphylaxis in patients with mastocytosis: a study on history, clinical features and risk factors in 120 patients. Allergy. 2008; 63(2): 226-232.
  3. FMS guideline Mastocytosis, 2022. The Dutch Society of Allergology and Clinical Immunology/ Nederlandse Vereniging voor Allergologie en Klinische Immunologie. Available at: [URL]. Accessed: 24. June, 2022.
  4. González de Olano D, de la Hoz Caballer B, Núñez López R, Sánchez Muñoz L, Cuevas Agustín M, Diéguez MC, et al. Prevalence of allergy and anaphylactic symptoms in 210 adult and paediatric patients with mastocytosis in Spain: a study of the Spanish network on mastocytosis (REMA). Clin Exp Allergy. 2007; 37(10): 1547-1555.
  5. Gülen T, Hägglund H, Dahlén B, Nilsson G. High prevalence of anaphylaxis in patients with systemic mastocytosis - a single-centre experience. Clin Exp Allergy. 2014; 44(1): 121- 129.
  6. Hermans MAW, Arends NJT, Gerth van Wijk R, van Hagen PM, Kluin-Nelemans HC, Oude Elberink HNG, et al. Management around invasive procedures in mastocytosis: An update. Ann Allergy Asthma Immunol. 2017; 119(4): 304-309.
  7. Hermans MAW, Rietveld MJA, van Laar JAM, Dalm VASH, Verburg M, Pasmans SGMA, et al. Systemic mastocytosis: A cohort study on clinical characteristics of 136 patients in a large tertiary centre. Eur J Intern Med. 2016; 30: 25-30.
  8. Hermans MAW, van der Vet SQA, van Hagen PM, van Wijk RG, van Daele PLA. Low frequency of acetylsalicylic acid hypersensitivity in mastocytosis: The results of a double-blind, placebo-controlled challenge study. Allergy. 2018; 73(10): 2055-2062.
  9. Schwaab J, Brockow K, Riffel P, Lübke J, Naumann N, Jawhar M, et al. Low risk of contrast media-induced hypersensitivity reactions in all subtypes of systemic mastocytosis. Ann Allergy Asthma Immunol. 2022; 128(3): 314-318.
  10. Thong BY, Tan TC. Epidemiology and risk factors for drug allergy. Br J Clin Pharmacol. 2011; 71(5): 684-700.

Autorisatiedatum en geldigheid

Laatst beoordeeld  : 28-11-2022

Laatst geautoriseerd  : 28-11-2022

Geplande herbeoordeling  :

Validity

The Radiological Society of the Netherlands (NVvR) will determine around 2027 if this guideline (per module) is still valid and applicable. If necessary, the scientific societies will form a new guideline group to revise the guideline. The validity of a guideline can be shorter than 5 years, if new scientific or healthcare structure developments arise, that could be a reason to commence revisions. The Radiological Society of the Netherlands is the owner of this guideline and thus primarily responsible for the actuality of the guideline. Other scientific societies that have participated in the guideline development share the responsibility to inform the primarily responsible scientific society about relevant developments in their field.

Initiatief en autorisatie

Initiatief:
  • Nederlandse Vereniging voor Radiologie
Geautoriseerd door:
  • Nederlandse Internisten Vereniging
  • Nederlandse Vereniging van Maag-Darm-Leverartsen
  • Nederlandse Vereniging voor Cardiologie
  • Nederlandse Vereniging voor Heelkunde
  • Nederlandse Vereniging voor Neurologie
  • Nederlandse Vereniging voor Obstetrie en Gynaecologie
  • Nederlandse Vereniging voor Radiologie
  • Nederlandse Vereniging voor Klinische Chemie en Laboratoriumgeneeskunde
  • Patiëntenfederatie Nederland
  • Nederlandse Vereniging voor Allergologie en Klinische Immunologie
  • Nederlandse Vereniging voor Endocrinologie
  • Nederlandse Vereniging voor Vaatchirurgie

Algemene gegevens

General Information

The Kennisinstituut van de Federatie Medisch Specialisten (www.kennisinstituut.nl) assisted the guideline development group. The guideline was financed by Stichting Kwaliteitsgelden Medisch Specialisten (SKMS) which is a quality fund for medical specialists in The Netherlands.

Samenstelling werkgroep

Guideline development group (GDG)

A multidisciplinary guideline development group (GDG) was formed for the development of the guideline in 2020. The GDG consisted of representatives from all relevant medical specialization fields which were using intravascular contrast administration in their field.

 

All GDG members have been officially delegated for participation in the GDG by their scientific societies. The GDG has developed a guideline in the period from June 2020 until November 2022. The GDG is responsible for the complete text of this guideline.

 

Guideline development group

  • Dekkers I.A. (Ilona), clinical epidemiologist and radiologist, Leiden University Medical Center, Leiden
  • Geenen R.W.F. (Remy), radiologist, Noordwest Ziekenhuisgroep, Alkmaar
  • Kerstens M.N. (Michiel), internist-endocrinologist, University Medical Centre Groningen
  • Krabbe J.G. (Hans), clinical chemist-endocrinologist, Medisch Spectrum Twente, Enschede
  • Rossius M.J.P. (Mariska), radiologist, Erasmus Medical Centre, Rotterdam
  • Uyttenboogaart M. (Maarten), neurologist and neuro-interventionalist, University Medical Centre Groningen
  • van de Luijtgaarden K.M. (Koen), vascular surgeon, Maasstad Ziekenhuis, Rotterdam
  • van der Molen A.J. (Aart), chair guideline development group, radiologist, Leiden University Medical Center, Leiden
  • van der Wolk S.L. (Sabine), gynaecologist-obstetrician, Haga Ziekenhuis, Den Haag
  • van de Ven A.A.J.M. (Annick), internist-allergologist-immunologist, University Medical Centre Groningen (until 1.7.2022)
  • van der Houwen, T.B. (Tim), internist-allergologist-immunologist, Amsterdam University Medical Center (from 1.7.2022)

Invited experts

  • van Maaren M.S. (Maurits), internist-allergologist-immunologist, Erasmus MC, Rotterdam

Belangenverklaringen

Conflicts of interest

The GDG members have provided written statements about (financially supported) relations with commercial companies, organisations or institutions that were related to the subject matter of the guideline. Furthermore, inquiries have been made regarding personal financial interests, interests due to personal relationships, interests related to reputation management, interest related to externally financed research and interests related to knowledge valorisation. The statements on conflict of interest can be requested from the administrative office of Kennisinstituut van de Federatie Medisch Specialisten (secretariaat@kennisinstituut.nl) and were summarised below.

 

Last name

Function

Other positions

Personal financial

interests

Personal relations

Reputation management

Externally financed

research

Knowledge valorisation

Other interests

Signed

Actions

Dekkers IA

Radiologist, LUMC

Clinical Epidemiologist

 

Member of contrast media safety committee, European Society of Urogenital Radiology (no payment)

 

Member, Gadolinium Research and Education Committee, European Society of Magnetic Resonance in Medicine, and Biology (no

payment)

No

No

No

No

No

Received consultancy fees from Guerbet, 2019-

2022

July 24th, 2020, Reaffirmed October 12th, 2022

No restrictions: received in part 3 of the guideline speaker fees, but this guideline does not mention specific medication, not of working mechanism, nor of side effects.

Geenen RWF

Radiologist, Noordwest ziekenhuisgroep

/Medisch specialisten

Noordwest

Member of contrast media safety

committee, European

Society of Urogenital

Radiology (no payment)

No

No

No

No

No

No

April 11th, 2020, Reaffirmed October 12th,

2022

No restrictions

Houwen T, van der

Internist - Immunologist - Allergologist, Amsterdam UMC, also seconded allergologist in Huid Medisch

Centrum

None

None

None

None

None

None

None

July 11th, 2022 Reaffirmed October 12th, 2022

No restrictions

Kerstens MN

Internist- endocrinologist, UMCG

Chairman Bijniernet (no payment)

No

No

No

No

No

No

July 1st, 2020, reaffirmed October 25th,

2022

No restrictions

Krabbe JG

Clinical chemist, Medisch Spectrum Twente

No

No

No

No

No

No

No

September 1st, 2020,

Reaffirmed October 13th, 2022

No restrictions

Luijtgaarden KM, van de

Vascular surgeon, Maasland Ziekenhuis

No

No

No

No

No

No

No

August 1st, 2020,

reaffirmed October 26th, 2022

No restrictions

Molen AJ, van der

Radiologist LUMC

Member of contrast media safety committee, European Society of Urogenital Radiology (no

payment)

 

Member, Gadolinium Research and Education Committee, European Society of Magnetic Resonance in Medicine, and Biology (no

payment)

No

No

No

No

No

Received consultancy fees from Guerbet, 2019-

2022

July, 24th, 2020 Reaffirmed October 12th, 2022

No restrictions: received in part 3 of the guideline speaker fees, but this guideline does not mention

Specific medication, not

of working mechanism, nor of side effects.

Rossius MJP

Radiologist Erasmus Medical Centre

Medical coordinator (no payment)

No

No

No

No

No

No

April 7th, 2020, Reaffirmed October 13th,

2022

No restrictions

Uyttenboogaart M

Neurologist and neuro- interventionalist UMCG

Advisor International Federation of Orthopaedic Manipulative Physical Therapist / Nederlandse Vereniging Manuele Therapie

No

No

Subsidy Hart Stichting for CONTRAST

(Consortium of New Treatments in Acute Stroke): WP8 Stroke logistics and Epidemiology: financing of 2 PhD students by the Hart Stichting / PPS

Allowance

Work package leader CONTRAST

(Consortium of New Treatments in Acute Stroke): WP8 Stroke logistics and Epidemiology

No

No

June 30th, 2020, reaffirmed October 26th, 2022

No restrictions: the CONTRAST

consortium wp8 is only about organisation and treatment of stroke.

Stroke is not in this guideline.

Ven AAJM, van de

Internist- allergologist- immunologist, UMCG

Education and research related to work as internist-

allergist

No

No

No

No

No

No

April 7th, 2020, Reaffirmed October 19th, 2022

No restrictions

Wolk S, van der

Gynaecologist- obstetrician, Haga Ziekenhuis

No

No

No

No

No

No

No

June 30th, 2021, reaffirmed October 25th,

2022

No restrictions

Inbreng patiëntenperspectief

Input of patient’s perspective

The guideline does not address a specific adult patient group, but a diverse set of diagnoses. Therefore, it was decided to invite a broad spectrum of patient organisations for the stakeholder consultation. The stakeholder consultation was performed at the beginning of the process for feedbacking on the framework of subjects and clinical questions addressed in the guideline, and during the commentary phase to provide feedback on the concept guideline. The list of organisations which were invited for the stakeholder consultation can be requested from the Kennisinstituut van de Federatie Medisch Specialisten (secretariaat@kennisinstituut.nl). In addition, patient information on safe use of contrast media in pregnancy and lactation was developed for Thuisarts.nl, a platform to inform patients about health and disease.

Implementatie

Implementation

During different phases of guideline development, implementation and practical enforceability of the guideline were considered. The factors that could facilitate or hinder the introduction of the guideline in clinical practice have been explicitly considered. The implementation plan can be found in the ‘Appendices to modules’. Furthermore, quality indicators were developed to enhance the implementation of the guideline. The indicators can also be found in the ‘Appendices to modules’.

Werkwijze

Methodology

AGREE

This guideline has been developed conforming to the requirements of the report of Guidelines for Medical Specialists 2.0 by the advisory committee of the Quality Counsel (www.kwaliteitskoepel.nl). This report is based on the AGREE II instrument (Appraisal of Guidelines for Research & Evaluation II) (www.agreetrust.org), a broadly accepted instrument in the international community and based on the national quality standards for guidelines: “Guidelines for guidelines” (www.zorginstituutnederland.nl).

 

Identification of subject matter

During the initial phase of the guideline development, the GDG identified the relevant subject matter for the guideline. The framework is consisted of both new matters, which were not yet addressed in part 1 and 2 of the guideline, and an update of matters that were subject to modification (for example in case of new published literature). Furthermore, a stakeholder consultation was performed, where input on the framework was requested.

 

Clinical questions and outcomes

The outcome of the stakeholder consultation was discussed with the GDG, after which definitive clinical questions were formulated. Subsequently, the GDG formulated relevant outcome measures (both beneficial and harmful effects). The GDG rated the outcome measures as critical, important and of limited importance (GRADE method). Furthermore, where applicable, the GDG defined relevant clinical differences.

 

Search and select

For clinical questions, specific search strategies were formulated, and scientific articles published in several electronic databases were searched. First, the studies that potentially had the highest quality of research were reviewed. The GDG selected literature in pairs (independently of each other) based on the title and abstract. A second selection was performed by the methodological advisor based on full text. The databases used, selection criteria and number of included articles can be found in the modules, the search strategy in the appendix.

 

Quality assessment of individual studies

Individual studies were systematically assessed, based on methodological quality criteria that were determined prior to the search. For systematic reviews, a combination of the AMSTAR checklist and PRISMA checklist was used. For RCTs the Cochrane risk of bias tool and suggestions by the CLARITY Group at McMaster University were used, and for cohort studies/observational studies the risk of bias tool by the CLARITY Group at McMaster University was used. The risk of bias tables can be found in the separate document Appendices to modules.

 

Summary of literature

The relevant research findings of all selected articles were shown in evidence tables. The evidence tables can be found in the separate document Appendices to modules. The most important findings in literature were described in literature summaries. When there were enough similarities between studies, the study data were pooled.

 

Grading quality of evidence and strength of recommendations

The strength of the conclusions of the included studies was determined using the GRADE- method. GRADE stands for Grading Recommendations Assessment, Development and Evaluation (see http://www.gradeworkinggroup.org) (Atkins, 2004). GRADE defines four levels for the quality of scientific evidence: high, moderate, low, or very low. These levels provide information about the certainty level of the literature conclusions (http://www.guidelinedevelopment.org/handbook).

 

The evidence was summarized in the literature analysis, followed by one or more conclusions, drawn from the body of evidence. The level of evidence for the conclusions can be found above the conclusions. Aspects such as expertise of GDG members, local expertise, patient preferences, costs, availability of facilities and organisation of healthcare aspects are important to consider when formulating a recommendation. These aspects are discussed in the paragraph justifications. The recommendations provide an answer to the clinical question or help to increase awareness and were based on the available scientific evidence and the most relevant justifications.

 

Appendices

Internal (meant for use by scientific society or its members) quality indicators were developed with the guideline and can be found in the separate document Appendices to modules. In most cases, indicators were not applicable. For most questions, additional scientific research on the subject is warranted. Therefore, the GDG formulated knowledge gaps to aid in future research, which can be found in the separate document Appendices to modules.

 

Commentary and authorisation phase

The concept guideline was subjected to commentaries by the involved scientific societies. The list of parties that participated in the commentary phase can be requested from the Kennisinstituut van de Federatie Medisch Specialisten (secretariaat@kennisinstituut.nl). The commentaries were collected and discussed with the GDG. The feedback was used to improve the guideline; afterwards the GDG made the guideline definitive. The final version of the guideline was offered to the involved scientific societies for authorization and was authorized.

 

Literature

Brouwers MC, Kho ME, Browman GP, et al. AGREE Next Steps Consortium. AGREE II: advancing guideline development, reporting and evaluation in health care. CMAJ. 2010; 182(18): E839-E842.

Medisch Specialistische Richtlijnen 2.0. Adviescommissie Richtlijnen van de Raad Kwaliteit, 2012. Available at: [URL].

Schünemann H, Brożek J, Guyatt G, et al. GRADE handbook for grading quality of evidence and strength of recommendations. Updated October 2013. The GRADE Working Group, 2013. Available at: [URL].

Schünemann HJ, Oxman AD, Brozek J, et al. Grading quality of evidence and strength of recommendations for diagnostic tests and strategies. BMJ. 2008;336(7653):1106- 1110. Erratum published in: BMJ 2008;336(7654).

Ontwikkeling van Medisch Specialistische Richtlijnen: stappenplan. Kennisinstituut van Medisch Specialisten, 2020.

Volgende:
Jodiumhoudend CM en Diabetes Mellitus (DM)