Background
The World Health Organization (WHO) Department of Nutrition and Food Safety is updating guidance on indicators for assessing iodine status. The programme managers guide on the Assessment of iodine deficiency disorders and monitoring (3rd edition) was published in 2007 jointly by WHO, UNICEF, and the International Council for the Control of Iodine Deficiency Disorders (now the Iodine Global Network)1. Urinary iodine is a priority indicator for the assessment of iodine intake and status in populations and is assessed from spot or 24-hour urine samples in field studies and surveys. WHO aims to update recommendations for the assessment of iodine status in populations, including the use of urinary iodine concentrations (UIC) as an indicator of recent iodine intake and status. WHO has identified questions about the use of urinary iodine and its interpretation, and new data may be available to inform the revision of current guidance.
Scope
WHO is seeking authors to develop a systematic review on the relationship between UIC and health outcomes associated with iodine intake. Intake will be considered on a continuum. At deficient and toxic intakes, overt clinical manifestations are detectable, and/or distinct changes in thyroid hormones are measurable. At intakes above overt deficiency yet below optimal intakes, and above requirements but below toxicity, the picture is less clear. Obvious clinical manifestations of sub-optimal or above-requirement iodine intakes are absent, but changes in thyroid volume may start to be detectable by ultrasound.
WHO is seeking support from individuals or groups with relevant expertise and experience to systematically review and assess all available evidence for addressing the following key question:
- What are the UIC thresholds that indicate a population risk of (i) iodine deficiency, (ii) iodine insufficiency, (iii) excessive intakes, and (iv) toxicity
- Population: All population groups by age and physiological status
- Index factor: urinary iodine measured by 24-hour urinary iodine excretion or spot urinary iodine concentrations
- Outcomes related to health (specific to target population): may include but not be limited to hypothyroidism, hyperthyroidism, thyrotoxicosis, goitre, stillbirth or miscarriage, congenital abnormalities, and cognitive development.
These thresholds are used to inform policy decision-making and actions. It is proposed that both a prognostic/risk factor review and data mapping are used in the update. Evidence will be gathered on all population groups, after which a decision will be made for which population groups sufficient evidence exists for the update or development of thresholds.
How to apply for a call for an expression of interest
Interest in conducting this review must be expressed through the submission of a proposal that covers the proposed key question.
The proposal should demonstrate a team with appropriate experience and expertise in both the topic of the review and the required systematic review methods. Applications are encouraged from teams that include expertise in biochemistry, endocrinology, programme implementation, statistics, and review methods.
Authors must be willing to work with an expert in prognostic/risk factor systematic reviews if sufficient experience is not available within the team. All named authors should meet the ICMJE criteria for authorship of a publication (ICMJE, 2024). Authors are advised to give due consideration to the resources needed to undertake a prognostic/risk factor systematic review, of which the most important resource is time.
It is expected that authors will work closely with the WHO technical team to define and refine the protocol, as well as report results according to best practice reporting guidelines and WHO templates and requirements. Prospective registration of the title in PROSPERO will be required.
Kindly send your proposals to the following e-mail address: NFS@who.int with the email subject "Proposal urinary iodine review".
Required information
- Contact information for the main focal point only (i.e. Lead Investigator)
- Cover letter/statement of motivation, including a maximum of 600 words detailing why your team is submitting this Expression of Interest, and why you believe your team is the most suitable to undertake this work. The letter must highlight the interested author’s/team’s relevant experience with conducting complex reviews, including the most relevant references of reviews that they have published in peer-reviewed journals. Please only apply if you and your team have this experience and expertise;
- Proposed fee for undertaking the work (in USD);
- Ideal start date and completion dates to undertake the work;
- ONE document (ideally in PDF format) that includes all Curriculum Vitae (CV) of the proposed research team, highlighting key references to relevant reviews;
- ONE document (ideally in PDF format) that includes a brief biography of each research team member (max 150 words per person);
- The proposal should outline the background and justification for the review, search strategy, and databases to be searched, inclusion/exclusion criteria, specific data they will extract from each study (ie. individual-level data), the process of data extraction, and analytical approach. This description should reflect the scope of work described above. Author(s) teams should demonstrate capacity to conduct the review(s) within the timeline indicated below, and accessibility to required publications. Successful authors will be required to submit a protocol prior to performing the review.
- The review should be completed by end of August 2024.
- Send your proposals to the following e-mail address nfs@who.int with the email subject "Proposal urinary iodine review".
Only candidates under serious consideration will be contacted. Respondents to this call may also be considered for future calls for authors regarding additional iodine indicators. Deadline for submissions: 15 March 2024, 16:00 (CET)
1 WHO, UNICEF, ICCIDD. Assessment of iodine deficiency disorders and monitoring their elimination. A guide for programme managers, 3rd Ed. Geneva: World Health Organization; 2007