Disease characteristics and long-term outcomes of cyclic vomiting syndrome in Singaporean children

Table 2 A summary of worldwide pediatric cyclic vomiting syndrome cohort studies

Ref.	Cohort size	Mean age of onset	Overall sex ratio (male:female)	Concomitant incidence of migraine (%)	Mean frequency of attacks (before prophylaxis)	Response to prophylaxis
Abu-Arafeh et al[20]	34 children	5 years	1:1	21	8 episodes/year	Not described
Li et al[21]	214 children	6 years	1:3	30	Not described	Not described
Ertekin et al[22]	24 children	7 years	1:2	25	Not described	Not described
Haghighat et al[14]	181 children	5 years	1:1	20	6 episodes/year	Not described
Liao et al[12]	24 children	7 years	2:1	Not described	2 episodes/year	1 episode/year
Foreman et al[23]	42 children	4 years	1:1	4	12 episodes/year	Not described
Dipasquale et al[24]	57 children	8 years	1.3:1	Not described	Not described	Not described
Singapore	32 children	7 years	1:2	7	4 episodes/year	1 episode/year