Table 1

Characteristics of included studies

StudyCohort descriptionnJCTarget populationALGReference standardSENSPECPPVNVP
Alves8≥1 swollen joint OR ≥2 painful joints or loss of movement AND MST>1 h, unable to clench in the morning, pain when shaking hands, difficulty wearing ring or shoes, family history of RA, unexplained fatigue <1 year;51344joint symptoms1MTX 12 months0.740.650.760.63
1Persistent disease after 1 year0.690.720.900.40
Alves23Early arthritis or patients with joint symptoms; ≥2 swollen or tender joints; symptom duration ≤12 months736NRJoint symptoms1Persistent disease (synovial swelling or DMARD) 12 months0.530.60ndnd
Berglin24Early arthritis; presence of synovitis in ≥1 joint at baseline; no other diagnosis than RA better explaining synovitis; disease duration ≤1 year; ≥1 year follow-up313NREarly arthritis patients2+3MTX 12 months0.640.52ndnd
Expert opinion 12 months0.910.65ndnd
Biliavska22 Early arthritis; >18 years, ≥1 swollen joint; symptom duration <16 weeks, no prior DMARD treatment;30366/68Early arthritis patients2Expert opinion 12 months0.850.640.680.82
DMARD 12 months0.800.630.710.73
MTX 12 months0.840.570.530.85
Expert opinion + DMARD 12 months0.790.660.750.70
Early arthritis patients, exclude other diagnosis2+3Expert opinion 12 months0.80.610.820.71
DMARD 12 months0.850.640.740.78
MTX 12 months0.840.540.570.82
Expert opinion + DMARD 12 months0.800.640.780.68
Britsemmer9Early arthritis ≥18 years, ≥2 swollen joints, symptom duration <2 years, no prior DMARD therapy; followed-up for ≥2 years45528All early arthritis patients, exclude other diagnosis2+3+4MTX 12 months0.850.500.860.49
DMARD 12 months0.900.490.790.70
Erosive disease0.910.210.220.91
Cader10Early arthritis with clinical synovial swelling of ≥1 joint; onset symptom ≤3 months follow-up for ≥18 months,20566/68Early arthritis patients, exclude other diagnosis2+3DMARD 18 months0.620.780.750.66
MTX 18 months0.680.720.570.81
Chitale25Early RA patients; symptom duration ≤12 months; started with DMARDs20844Early RA patients (<=12 months) n=208NRExpert opinion+ DMARD 12 months0.82ndndnd
Very early RA patients (<=3 months) n=910.81ndndnd
Cornec11Early arthritis ≥16 years old; at least one swollen joint; absence of any other joint disease; symptom duration ≤1 year16440All arthritis patients2Expert opinion 10 yr0.600.890.740.81
Excl other diagnosis2+3Expert opinion 10 yr0.640.760.740.67
Excl RA typ erosions2+3+4Expert opinion 10 yr0.590.890.760.67
De Hair12Early arthritis; symptom duration ≤1 year30166/68Early arthritis patients21987 ACR baseline0.930.740.570.96
1987 ACR 2 year0.880.830.740.93
Duer-Jensen26Patients with joint symptoms, ≥2 tender/swollen joints in MCP, PIP, wrist or MTP joints for >6 weeks but <24 months11966/68Joint symptoms11987 ACR criteria0.370.930.630.83
+MRI ≥1 Syn0.390.850.460.82
+MRI ≥2 Syn0.390.910.580.82
+MRI ≥3 Syn0.390.920.610.83
+MRI ≥1BE0.460.810.430.83
Fautrel13Early arthritis patients; 18–70 years old, ≥2 swollen joints, disease duration >6 weeks but <6 months, no previous DMARD or steroids or stopped for >2 weeks before inclusion81128Arthritis patient exclude other diagnosis2+3Expert opinion0.950.340.570.89
Expert opinion 2 yr0.910.350.610.78
MTX 6 months0.880.320.620.67
DMARD 6 months0.860.460.860.46
Garcia27Early arthritis; ≥1 SJC; symptom duration >4 weeks and <1 year; n=260260NREarly arthritis2Expert opinion 2 year0.880.720.670.91
Jung14Undifferentiated arthritis10266/68All UA patientsUAExpert opinion0.480.720.300.84
Jung15Disease duration ≤12 months, RA according to 1987 ACR criteria;170NREarly RA patients according to 1987 criteriaRA1987 ACR criteria0.92ndndnd
Kaarela16121 RA, 95 controls (61 reA, 19 PsA, 15 SpA) at baseline ≥16 years, ≥1 peripheral swollen joint; Disease duration ≤6 months21640All patients (RA+control)2Expert opinion 20 yr0.790.960.960.78
Only RA patientsRA0.79ndndnd
Kaneko17Patients with joint symptoms including arthralgia, joint swelling and morning stiffness;31366/68Joint symptoms1Expert opinion +DMARD0.720.900.700.91
Arthritis excl other diagnosis2+30.740.710.930.36
Kennish42Joint symptoms; exclude if better explanation than RA;126NRJoint symptoms2+3Expert opinion0.970.550.440.98
Luchikhina30Early arthritis; symptom duration ≤12 months; ≥1 swollen joint without definite symptoms of other disease413NREarly arthritis patients2+3Expert opinion 1 year0.890.63ndnd
RF negative patients0.730.85ndnd
ACPA negative patients0.730.84ndnd
Luchikhina29Early arthritis; symptom duration ≤12 months; ≥1 swollen joint without definite symptoms of other disease413NREarly arthritis patients2+3Expert opinion 1 year0.890.63ndnd
Symptom duration <=3 months0.880.97ndnd
Symptom duration 3–12 months0.890.51ndnd
Meric31Undifferentiated arthritis; ACPA pos;32NRUA; ACPA posUA1987 ACR 2 years0.860.10.680.25
Mjavaatten33Early arthritis; ≥1 swollen joint; symptom duration ≤16 weeks; age 18–75298NREarly arthritis2Expert opinion 6 months0.890.83ndnd
Mjaavatten32Early arthritis; ≥1 joint; disease duration ≤16 weeks; age btw 18–75 years; n=343343NREarly arthritis2Clinical RA diagnosis0.860.800.620.94
Mourao18Very early arthritis (≤6 weeks) ≥4 swollen and/or tender joint3766/68Arthritis or joint symptomsNRExpert opinion + 1987 ACR0.710.560.680.60
Nicolau34Very early arthritis; ≥18 years; ≥ 2 SJC; symptom duration ≥6 weeks and <6 months; DMARD/steroid naive310NRVery early arthritis2Expert opinion 6 years0.860.59ndnd
Nicolau35Very early arthritis (VERA); ≥18 years; ≥ 2 SJC; symptom duration ≥6 weeks and <6 months; DMARD naive; steroid naive310NRVERA excl other diagnosis and >=1 eros2+3+4Expert opinion after 6 years0.860.59ndnd
VERA excl other diagnosis and >=3 eros2+3+40.860.69ndnd
VERA; excl other diagnosis and >=1 eros2+3+4Erosive disease after 3 years0.950.40ndnd
VERA; excl other diagnosis and ≥3 eros2+3+40.950.40ndnd
Renases41Early arthritis; symptom duration ≥4 months and <12 months; ≥2 swollen joints, >16 years old; exclude if other explanation of arthritis than RA or previous DMARD/steroid therapy20176Early arthritis; Exclude if otherdiagnosis and RA typical erosiosn2+3+4MTX 12 months0.800.620.900.43
2+3+4DMARD 12 months0.750.730.980.14
2+3+4Expert opinion after 1 year0.870.730.910.64
2+3+41987 ACR at baseline0.940.530.700.88
Rintelen36Established RA (fulfilment 1987 ACR criteria); n=979744Established RARA1987 ACR criteria0.59ndndnd
Sakellariou37Patients with RA or UA according to 1987 criteria;266NRRA or UA patientsRA/UAMTX 12 months0.870.57ndnd
DMARD 12 months0.870.63ndnd
Salehi19Early rheumatoid arthritis diagnosed by expert, disease duration<1 year;24366/68RA patientsRAExpert opinion baseline0.66ndndnd
1987 ACR baseline0.760.730.850.61
Tamai38Early arthritis ≥1 swollen joint;138NREarly arthritisNRDMARD 12 months0.760.710.860.56
Tamai39UA; not fulfil 1987 ACR criteria at baseline; apply criteria only to those with swelling of at least one joint;85NRUndifferentiated arthritisUA1987 ACR criteria at 12 months0.670.540.790.39
Van der Linden20Early arthritis; confirmed by physical examination; symptom duration <2 years, follow-up for >1 year,225866/68Arthritis excl other diagnosis2+3MTX 12 months0.740.600.560.86
Arthritis excl other diagnosis + x-ray2+3+40.880.540.540.88
Arthritis excl other diagnosis2+3DMARD 12 months0.740.740.840.60
Arthritis excl other diagnosis + x-ray2+3+40.790.680.820.64
Arthritis excl other diagnosis2+3Persistent disease0.710.650.840.46
Arthritis excl other diagnosis + x-ray2+3+40.770.560.820.48
44Arthritis excl other diagnosis2+3MTX 12 months0.830.600.560.85
Arthritis excl other diagnosis + x-ray2+3+40.870.540.540.88
Arthritis excl other diagnosis2+3DMARD 12 months0.730.740.840.60
Arthritis excl other diagnosis + x-ray2+3+40.790.680.820.63
Arthritis excl other diagnosis2+3Persistent disease0.710.650.840.48
Arthritis excl other diagnosis + x-ray2+3+40.770.560.820.48
28Arthritis excl other diagnosis2+3MTX 12 months0.750.660.580.82
Arthritis excl other diagnosis + x-ray2+3+40.830.590.730.64
Arthritis excl other diagnosis2+3DMARD 12 months0.650.790.850.55
Arthritis excl other diagnosis + x-ray2+3+40.740.730.830.60
Arthritis excl other diagnosis2+3Persistent disease0.650.690.850.43
Arthritis excl other diagnosis + x-ray2+3+40.740.590.830.46
Varache21Early arthritis patients >18 years, >1 swollen joint (clinical); absence of previous joint disease; disease duration <1 year27040Arthritis2Expert +DMARD0.580.860.700.78
Excl other diagnosis2+30.570.760.750.58
Excl RA erosions2+3+40.570.760.750.58
Westhoff40early arthritis or patients with joint symptoms (≥1 swollen or tender joint); symptom duration 6–26 weeks147NRJoint symptomsNRExpert opinion 3 months0.710.630.880.36
  • ACR, American college of rheumatology; ACPA, anticitrullinated-peptide autoantibodies; ALG: algorithm according to the 2010 ACR/EULAR criteria: 1: patients with joint symptoms; 2: include only patients with clinically evident synovitis; 3: include only arthritis patients with no better explanation of their synovitis; 4: consider; BE, bone oedema; DMARD, disease modifying antirheumatic drug; dur, duration; excl, exclude; Expert, diagnosis of RA, according to Expert opinion; PIP, proximal interphalangeal joint; MCP, metacarpo-phanlangeal joint; MRI, magnet resonance imaging; MST, morning stiffness; MTP, metatarso-phalangeal joint; MTX, methotrexate; nd, not done; NPV, negative predictive value; NR, not reported; PPV, positive predictive value; PsA, psoratic arthritis; RA, rheumatoid arthritis; RA typical erosions on x-ray; SEN, sensitivity; SPEC, specificity; SpA, ankylosing spondylitis; symp, symptom; Syn, synovitis; UA, undifferentiated arthritis; VERA, very early arthritis; yr, year.