Iranian school-aged twin registry: preliminary reports and project progress

Abstract

Background National Persian school-aged twin registry was established to provide a platform for twin studies. In this report, we describe defining registry characteristics, database design, and preliminary results regarding gathered data in the first phase of the registry program. Method Through focus group discussions, the required data elements to design the database and data collection process were defined. First, a list of twins in school-aged groups was retrieved from the electronic database of the Ministry of Education. Tehran schools were selected for the first phase of our registry. Standard “Pea-in-Pods” questionnaire and twins’ similarity questionnaires were filled out by the parents themselves in addition to demographic information. Data were analyzed using SPSS v.22. Results The first national school-aged twin registry was established in 2018. Firstly, the required data sets and data collection process were defined using focus group discussions. At the country level, the initial information on 189,738 students was retrieved from the national database of the Ministry of Education. They were born between 2003 and 2017, of which 94,997 are boys (50.1%) and 94,741 are girls (49.9%). Of them, a total of 5,642 pairs of school-aged twins participated in the first phase of our program. Our sample size comprised 9772 twins, 906 triples, and 92 quadruplets. The analysis of the zygosity questionnaire showed that 14% of twin pairs were identified as monozygotic twins. Conclusion Recruiting school-aged twins through school health assistants leads to high enrollment and decreasing costs for the twin registry. The study showed a high rate of dizygotic twins that need to be verified by twin bio-sample in the next phase of studies.

Conceptual framework for establishing twins prevention and continuous health promotion programme: a qualitative study

“…In addition, school health experts (school nurses) play a crucial role as recruitment facilitators in school-aged twins. According to a previous study, there are approximately 189 738 twin students in Iran and 5642 twin students in Tehran 27. Similar studies have shown that schools can help children and adolescents develop healthy habits that will also benefit their families, friends and communities.…”

“…By promoting their health, schools can enhance the quality of life of children and teenagers. School staff, such as school health experts (school nurses), could serve as recruitment facilitators to improve participant retention 27 44. Therefore, school-aged twins are considered a desirable group of twins in registries.…”

“…According to a previous study, there are approximately 189 738 twin students in Iran and 5642 twin students in Tehran. 27 Similar studies have shown that schools can help children and adolescents develop healthy habits that will also benefit their families, friends and communities. That is why the WHO started the Health Promotion School (HPS) approach in 1995.…”

“…6 24-26 More detailed information is available in the researchers' recent paper. 27 Our experience with the twin follow-up programme within the Persian Twin Registry showed that one of the most significant obstacles was recruiting and retaining twins in a continuous follow-up programme. This may be due to participants having direct access to specialised care in Iran, which allows them to choose their healthcare provider, potentially decreasing their motivation to participate in regular twin follow-up programmes.…”

“…These challenges include high costs associated with data entry, non-cooperation of twins and their families, tracing twins, a shortage of skilled human resources, loss of follow-up and the need for infrastructure to support a twin health follow-up programme 6 24–26. More detailed information is available in the researchers’ recent paper 27…”