Congenital Hypothyroidism Screening Program in Iran; a Systematic Review and Metaanalysis

Objective: unrecognized congenital hypothyroidism (ch) leads to mental retardation. newborn screening and thyroid therapy started within 2 weeks of age can normalize cognitive development. in this systematic review, the local results of the national ch screening program in different provinces in iran are reviewed and evaluated. methods: literature on the ch screening, the national databases including sid, medlib, iran medex, magiran as well as international databases including pubmed/ medline, isi web of knowledge and web of science, embase, scopus and google scholar. appraisal was guided by a checklist assessing clarity of aims and research questions. the 95% confidence intervals were calculated by i-square models. meta regression was introduced to explore the heterogeneity between studies. findings: we identified 25 samples including 1425124 neonates in our country. data were meta analyzed using random-effects models, and we found a tsh levels of 19633 babies in the first sampling were greater than the cut-off level (tsh ≥5miu/l). the pooled recall rate was 0.014 (95 % ci: 0.013 – 0.015). according to meta analysis the overall incidence of ch was 2/1000 (95% ci: .002 – .002). the incidence of ch did not appear to be increasing over time (p=0.08). conclusion: considering tsh ≥5miu/l as a cut-off point for recalling neonates and low positive predictive value (14%) of this point shows that more investigation and research is needed for establishing accurate level of tsh as a criterion for recalling patients.