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Objective: To describe changes in the iodine status of Tasmanians following voluntary fortification of bread with iodine in October 2001. Design and setting: Post‐intervention, cross‐sectional urinary iodine surveys of Tasmanian schoolchildren aged 8–11 years were used to assess population iodine status. Participants were selected using a one‐stage cluster sampling method. The sampling frame comprised classes containing fourth‐grade children from all Tasmanian government, Catholic and independent schools. Results were compared with pre‐intervention survey results. Main outcome measures: Median urinary iodine concentration (UIC) and percentage of UIC < 50 μg/L ascertained from spot urine samples. Results: Median UIC was 75 μg/L in 1998, 72 μg/L in 2000, 105 μg/L in 2003, 109 μg/L in 2004 and 105 μg/L in 2005. Median UIC in post‐intervention years (2003–2005) was significantly higher than in pre‐intervention years. The percentage of UIC results < 50 μg/L was 16.9% in 1998, 18.7% in 2000, 10.1% in 2003, 10.0% in 2004 and 10.5% in 2005. Conclusion: Despite methodological differences between the pre‐ and post‐intervention surveys, switching to iodised salt in bread appears to have resulted in a significant improvement in iodine status in Tasmania. Given iodine deficiency has been identified in other parts of Australia and in New Zealand, mandatory iodine fortification of the food supply in both countries is worthy of consideration. As voluntary fortification relies on industry goodwill, mandating fortification could be expected to enhance population reach and give a greater guarantee of sustainability in Tasmania.

Objective: To document the population iodine nutritional status in Australian schoolchildren. Design and setting: Cross‐sectional survey of schoolchildren aged 8–10 years, based on a one‐stage random cluster sample drawn from all Year 4 school classes in government and non‐government schools in the five mainland Australian states of New South Wales, Victoria, South Australia, Western Australia and Queensland. The study was conducted between July 2003 and December 2004. Participants: 1709 students from 88 schools (881 boys and 828 girls), representing 85% of the estimated target number of students. The class participation rate was 65%. Main outcome measures: (i) Urinary iodine excretion (UIE) levels (compared with the criteria for the severity of iodine deficiency of the World Health Organization/International Council for the Control of Iodine Deficiency Disorders: iodine replete, UIE ≥ 100 μg/L; mild iodine deficiency, UIE 50–99 μg/L; moderate iodine deficiency, UIE 20–49 μg/L; severe iodine deficiency, UIE < 20 μg/L); (ii) Thyroid volumes measured by ultrasound (compared with new international reference values). Results: Overall, children in mainland Australia are borderline iodine deficient, with a national median UIE of 104 μg/L. On a state basis, NSW and Victorian children are mildly iodine deficient, with median UIE levels of 89 μg/L and 73.5 μg/L, respectively. South Australian children are borderline iodine deficient, with a median UIE of 101 μg/L. Both Queensland and Western Australian children are iodine sufficient, with median UIE levels of 136.5 μg/L and 142.5 μg/L, respectively. Thyroid volumes in Australian schoolchildren are marginally increased compared with international normative data obtained from children living in iodine sufficient countries. There was no significant association between UIE and thyroid volume. Conclusion: Our results confirm the existence of inadequate iodine intake in the Australian population, and we call for the urgent implementation of mandatory iodisation of all edible salt in Australia.

A rurally based nurse-led FLS was associated with modest improvement after MTF. Consideration should be given to ways to strengthen the model of care to improve outcomes.

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