Table 2.
Characteristics of the included studies
| Authors, year | Country | Study period | Study design/population | Age of study population, years | Diagnosis criteria for Rett syndrome | Cases |
|---|---|---|---|---|---|---|
| Bienvenu et al. [13] (2006) | France | Born 1989–2000 | National population-based: Rett registry | 4–15 | Clinical and genetic | Rett |
| Magnússon et al. [14] (2001) | Iceland | Born 1974–1993 | National population-based: registers of tertiary hospitals | 5–24 | Clinical, pediatrician, psychiatrist (ICD-10) | ASD with Rett |
| Strømme et al. [15] (2000) | Norway, Akershus | Born 1980–1985 | Population-based: multiple search strategies | NR | Clinical (ICD-10 [code F84.2]) | MR with Rett |
| Isaksen et al. [16] (2012) | Norway, Oppland, and Hedmark | Born 1996–2002 | Population-based: multiple sources like registries, schools, hospitals, and public health services | 6–12 | Clinical, pediatrician, neurologists (ICD-10 [code F84.2]) | ASD with Rett |
| Sarajlija et al. [17] (2015) | Serbia | 1981–2001 | National population-based: registers of Mother and Child Health Institute of Serbia | <18 | Clinical and genetic | Rett |
| Aguilera et al. [18] (2007) | Spain, Seville | 2002–2003 | Population-based: all schools in the area | 3–21 | Clinical, confirmed by schools (DSM-IV, ICD-10) | ASD with Rett |
| Fombonne et al. [19] (2003) | UK, England, Wales, Scotland | 1999 | Population-based: Sample of Child Benefit Register | 5–15 | Clinical, psychiatrist (DSM-IV, ICD-10) | PDD with Rett |
| Chakrabarti et al. [20] (2005) | UK, Midlands | Born 1996–1998 | Population-based: Child Health Surveillance | 4–6 | Clinical, psychiatrist (DSM-IV) | PDD with Rett |
| Fehr et al. [21] (2011) | Australia | Born 1976–2006 | National population-based: multiple sources | 5–32 | Clinical and genetic | Rett |
| Wong et al. [22] (2007) | China, Hong Kong West | 2006 | Population-based: tertiary hospital | <35 | Clinical and genetic (DSM-IV) | Rett |
ASD Autism spectrum disorders, DSM-IV Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, ICD-10 International Classification of Diseases, Tenth Revision, MR Mental retardation, NR Not reported, PDD Pervasive developmental disorder, UK United Kingdom