Table 2

Characteristics of included studies

ReferenceDesignCountry of originNInclusion criteriaOutcome*Follow up
24RetrospectiveItaly, USA437JIA, minimum 4 years FU1b, 1c, 1e, 1f>4 years
34ProspectiveDenmark, Finland, Norway, Sweden440JIA, population based1b8 years
35Cross-sectionalTaiwan107JRA, minimum 1 year FU1d?†
36ProspectiveCanada356JIA, maximum 6 months FU1 g, 3a, 4b6 months
37RetrospectiveNorway55JIA, ERA only1b, 3gMedian 15.3 years (1b), median 23.0 years (3g)
38RetrospectiveUSA104JIA, RF+ and RF−poly only, minimum 6 mo FU1a, 1b>6—>36 months
39RetrospectiveBelgium, Germany, Switzerland, The Netherlands146JIA, FU >5 years1f5 years
40RetrospectiveItaly683JCA, minimum 1 years FU1hMean 10 years
41RetrospectiveNorway268JRA1i, 2a, 3fMedian 14.9 years
42RetrospectiveGermany171JCA, JSpA, population based1iMean 7.4 years
43ProspectiveUSA2704JIA2c, 3a?
44ProspectiveNorway84JRA and JSpA2a, 3bMean 9.7 years
45ProspectiveSweden132JCA, population based2b, 3d5 years
46RetrospectiveFrance207JIA, oligo-onset only2a6 years
47RetrospectiveCanada205JRA, oligo-onset only, minimum 5 years FU2c, 3cMedian 10.8 years (CHAQ 0–3 years earlier)
48RetrospectiveCanada181JRA, minimum 5 years FU, at least 8 years old2c, 3eMedian >9.2 years (2c), median >11.6 years (3e)
49ProspectiveUK740JIA, minimum 1 year FU3e>1 year
50ProspectiveSweden132JCA, population based3b, 4a17 years
51Cross-sectionalPortugal114JIA3aMedian 3 years†
52RetrospectiveCanada393JRA, minimum 5 years FU, at least 8 years old3a, 3eMedian >11.6 years
53RetrospectiveItaly, USA227JRA, maximum 6 months disease duration, minimum 5 years FU3e, 4d>5 years
54RetrospectiveItaly75JIA, oligo only3e>5 years, median >7 years
55RetrospectiveTurkey67JRA, minimum 3 years FU3eMean 4.8 years
56RetrospectiveCanada235JIA, minimum 6 moths FU4cMean >3.1 years
  • *1a: Wallace: achievement of CID in first year; 1b: Wallace: achievement of CRM and/or CR during FU; 1c: Wallace: duration first period CID; 1d: Wallace: duration first period CRM; 1e: Wallace: duration of AD before CID; 1f: Wallace: percentage of time spent in AD, CID, CRM and/or CR; 1g: Quasi Wallace: achievement of CID; 1h: Quasi Wallace: achievement of CR during FU; 1i: ACR: percentage of patients in remission at last FU visit; 2a: Dale radiographic classification; 2b: Cassidy radiographic classification; 2c: joint space narrowing, erosions and/or ankylosis on imaging; 3a: (C)HAQ continuous; 3b: (C)HAQ dichotomised >0; 3c: (C)HAQ dichotomised >0.12; 3d: (C)HAQ dichotomised >0.5; 3e: (C)HAQ dichotomised >0.75; 3f: SF-36 continuous; 3g: SF-36 PCS continuous; 4a: SF-36 MCS; 4b: JAQQ continuous; 4c: JAQQ, psychosocial function continuous; 4d: QOLS dichotomised >80.

  • †Time after diagnosis.

  • ‡These describe the same cohort, but different predictors, outcomes and follow-up.

  • ACR, American College of Rheumatology; AD, active disease; (C)HAQ, (childhood) health assessment questionnaire; CID, clinical inactive disease; CR, clinical remission off all medications; CRM, clinical remission on medication; ERA, enthesitis-related arthritis; FU, follow-up; JAQQ, juvenile arthritis quality of life questionnaire; JCA, juvenile chronic arthritis, JIA, juvenile idiopathic arthritis; JRA, juvenile rheumatoid arthritis; JSpA, juvenile spondyloarthropathy; MCS, mental component score; oligo, oligoarticular; PCS, physical component score; poly, polyarticular; QOLS, quality of life scales; RF, rheumatoid factor; SF-36, Short Form 36 items.