Table 1

Information collection

Identification of the studyTitle, first author’s last name, year of publication, journal, volume, number and pages
Study characteristicsParticipant recruitment period, country, region, study design, study site, study setting, sampling process, data collection time, sample size.
Participant characteristicsInformation on study inclusion and exclusion criteria, mean/median age, ethnicity, proportion of participants with any therapy.
Diagnosis and classification of the conditionMeasurement or diagnostic criteria used to define the condition (micronutrient deficiency), micronutrient evaluated, unit of measurement, cut-off point adopted.
Prevalence and incidenceNo of participants, total person follow-up time, no of cases of the condition, reported aetiologies, prevalence, incidence rate and their respective CIs and/or p value.