Table 1.

Prevalence of juvenile fibromyalgia syndrome in children and adolescents: review of the literature

References	Diagnostic criteria	Cohort variables	Country/prevalence
Buskila et al. J Rheumatol 1993; 20(2): 368-70.	1990 ACR criteria	338 healthy school children, 179 boys and 159 girls, aged 9 to 15 yrs.	Israel Prevalence 6.2%.
Clark et al. J Rheumatol 1998; 25(10): 2009-14.	1990 ACR criteria.	548 children, 264 boys and 284 girls, aged 9-15.	Mexico Prevalence 1.2%.
Mikkelsson et al. Pain 1997; 73(1): 29-35 and J Rheumatol 1999; 26(3): 674-82.	Structured pain questionnaire to assess the prevalence and persistence of self-reported musculo-skeletal pain symptoms and disability caused by pain.	1626 third and fifth grade schoolchildren	Finland Prevalence 1.3% at baseline.
Weir et al. J Clin Rheumatol 2006; 12(3): 124-8.	ICD-9 criteria (*)	2595 incident cases of adult and juvenile FMS	U.S.A The estimated prevalence per age group was: 0.5 to1% for 0-4 yrs; 1 to 1.4% for 5-9 yrs; 2 to 2.6% for 10-14 yrs; and 3.5 to 6.2% for 15-19 yrs.
Fuda A et al. Egypt Rheumatol Rehabil 2014; 41: 135-138	A questionnaire was completed by students. A clinical diagnosis of FM was established in only 25 cases.	2000 students: 960 boys (48%) and 1040 girls (52%). Ages: 9-15 yrs, mean 11.9 yrs	Egypt Prevalence 1.2%.

Legend: JFMS: Juvenile fibromyalgia syndrome; FM: fibromyalgia; (*) International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) codes to identify fibromyalgia cases (ICD code 729.1).