Osteoarthritis Initiative (OAI) Study Protocol

General Inclusion Criteria:

  • Men and women ages 45 – 79
  • With, or at risk for, symptomatic femoral-tibial knee OA
  • All ethnic minorities (focus on African-Americans)

Major Exclusion Criteria:

  • Inflammatory arthritis (RA)
  • Contraindication to 3T MRI
  • Bilateral end-stage knee OA

The Protocol and Appendices are available for download:

OAI Study Protocol and Appendices

Last modified on Oct 18, 2017

Progression Cohort:

Symptomatic Tibial-Femoral Knee OA (1,389 -- 29%), presence of BOTH osteophytes and frequent symptoms in 1 or both knees:

  • Definite Tibial - Femoral osteophyte (OARSI atlas grade 1-3) at baseline (clinic interpretation)
  • Symptoms: Pain, aching or stiffness on most days of a month in past year

Incidence Cohort

No Symptomatic Tibial-Femoral OA in either knee (3,285 -- 68%), at increased risk for symptomatic OA in 1 or both knees:

  • Frequent knee symptoms without x-ray OA
  • May have osteophytes in one or both knees, but not osteophytes and frequent symptoms in the same knee
  • Two or more other eligibility risk factors

Control Cohort

No Symptoms AND No Radiographic Tibial-Femoral or Patello-Femoral OA in either knee, No Risk Factors (122 -- 3%)