Goiter surveys

REQUIREMENTS FOR GOITER SURVEYS AND THE DETERMINATION OF THYROID SIZE... 

C. Perez, N.S. Scrimshaw, and J.A. Munoz, Technique of endemic goiter surveys, in "Endemic Goiter",... 

IODINE PROPHYLAXIS, GOITER SURVEY AND STUDIES OF IODINE EXCRETION... 

Lessons of goiter survey in Budapest schoolchildren, (in prepar.)... 

Thus thyroid ultrasound should be employed in endemic goiter surveys to limitate the sovraestimation of thyroid palpation. 

Large-scale, epidemiologic cross-sectional trials are too cost-intensive to be used as an instrument for regular monitoring of IDD. Instead of cross-sectional trials, periodic prevalence surveys are an adequate method to evaluate changes in goiter prevalence/UI over time (WHO, 2001). 

Periodic prevalence surveys for goiter are an adequate method to evaluate changes. 

Surveys on goiter in schoolchildren and on the iodine content of drinking water were conducted for the first time in four representative counties, namely, Houghton, Wexford, Midland and McComb. The prevalence of goiter was 38.6% among the 65537 school children studied. Salt containing potassium iodide (1 part in 5000) was introduced, and by 1929 the prevalence rate was reduced to 9% (Kimball, 1937). Brush and Airland (1952) conducted follow-up surveys on 53785 subjects in the same counties and found only 1.4% goiter prevalence. 

Urinary iodine concentration and palpation of goiter among schoolchildren is the most frequent method used by cross-sectional surveys to measure iodine deficiency. Because iodine is excreted by the kidneys, the urinary concentration of iodine is an indicator of iodine intake. Lower production of thyroxine leads to increased production of the thyroid-stimulating hormone, which results in thyroid hyperplasia known as goiter. The World Health Organization (2001) classifies iodine deficiency into mild, moderate and severe when urinary excretion is, respectively, 50—99, 20 9 and <20 p,g/l of urine. 

Note-. These communities were covered by oniy one survey, and the first to the iast coiumn represent the year when the surveys were conducted, the geographic iocation, the sampie of schooichiidren, the goiter prevaience measured by paipation and the mean or median of micrograms of urinary iodine per iiter. NA, not avaiiabie. 

The results of this analysis can be used for policy and planning purposes to show the incremental benefit of AP over and above the contribution of SP. This analysis has fully exploited published data to measure the likely contribution of AP and SP in Italy between the 1970s and 1990s. The cross-sectional and longitudinal surveys have provided a valid base to produce a method that can help policy makers to advocate the extra benefits of AP. Even if this natural experiment cannot produce the same evidence as a randomized community trial, the causal inference between the increase in urinary iodine and the decline in goiter with and without AP is clear, and the incremental cost-effectiveness of AP can be estimated. 

Measures to control IDD in Tibet were first undertaken by public health authorities in the 1970s. Since 1990 iodized salt and lOCs were employed intermittently on a small scale, with beneficial, but very limited results. The results of the 1997 National IDD Surveillance Survey from the TAR revealed that the household Qualified Iodized Salt Coverage Rate was only 6.2%, and that 29% of school-children had palpable goiter, while the median urinary iodine level of school-aged children was 55 J.g/l. 

Since the iodization of salt, there has been an increase in the daily consumption of iodine among the population, leading to a decrease in the prevalence of iodine deficiency disorders. In a survey (Toteja et ai, 2004) carried out on 1 45 264 children aged 6—12 years in 15 districts in India in 1997—2000, the goiter rate was found to have decreased to 4.78% as compared to a previous report of 21% in 1984—1986 (IGMR, 1989). Follow-up surveys carried out in the same region of the country over the period have shown a decrease in the prevalence of goiter over the years, as exemphfied by data from the National Capital Territory of Delhi (Table 87.1). 

By the early 1980s, the national goiter prevalence survey data demonstrated, however, that goiter was not localized, but rather affected all regions of India. In 1984, the Central Council of Health took the decision to iodize all edible salt throughout the country, and invited private sector participation in the production and distribution of iodized salt. USI was to be achieved completely in a phased manner by 1990. 

Mandating periodic cohort surveys for tracking the disappearance of IDD by assessments of goiter, urinary iodine, neonatal total goiter prevalence and other relevant indicators. 

A nationwide IDD survey carried out in 1996 (results presented in 1997 fully reported in 1998) for the first time in Bulgaria employed a combination of assessments of urinary iodine concentration and the presence of goiter... 

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