Status of nutrients important in brain function in phenylketonuria: a systematic review and meta-analysis

Table 2 Characteristics of the eligible studies

	n
Study design
Observational studies	58
Intervention studies	7
Countries of origin
European	48^a
USA	9
Rest of the world	8
Age groups of subjects
Children (< 14 yrs) only	24
Children and adolescents (< 19 yrs) only	15
Adults only	7
Mixed age group (infants/children, adolescent and adults)	19
Phentoytpe
Classical PKU only	26
Classical and moderate PKU	5
Insufficient details to determine sub-classifications of PKU	34
Information on dietary control
Information on dietary control provided^c	54
Information on dietary control not provided	11
Information on phe-free PS
Information on PS provided^d	36
Information on PS not provided	29

Notes: ^a3 Austria, 1 Czech Republic, 2 France, 9 Germany, 7 Greece, 3 Italy, 2 The Netherlands, 2 Poland, 1 Portugal, 1 Russia, 11 Spain, 1 Switzerland, 3 Turkey and 2 UK.
^b3 Japan, 2 Brazil, 1 Australia, 1 China and 1 Lebanon.
^cEither details of baseline Phe control at entry provided or the study entry criteria required that patients had to be well-controlled.
^dEither information detailing the specific PS used by patients or whether a supplementary source of the nutrients that were the subject of this review were taken by PKU subjects.
Data in bold is highly significant

ISSN: 1750-1172