Multicenter Osteoarthritis Study logo and title      

Multicenter Osteoarthritis Study (MOST)

A multicenter prospective observational study of risk factors for the development and progression of knee osteoarthritis and knee pain

MOST is a nationwide research study, sponsored by the National Institutes of Health / National Institute on Aging (part of the Department of Health & Human Services), that will help us better understand how to prevent and treat knee osteoarthritis, one of the most common causes of disability in adults.

This site is MOST Online, providing public access to the Multicenter Osteoarthritis Study data and knee images in accordance with the NIH Data Sharing Policy (NOT-OD-03-032, 2/26/03).

Summary of Data and Images
Clinical Data
  • 84-month Telephone Interview and Clinic Visit (N=2638 participants)
  • 72-month Telephone Interview (N=2715 participants)
  • 60-month Telephone Interview and Clinic Visit (N=2768 participants)
  • 30-month Telephone Interview and Clinic Visit (N=2969 participants)
  • 15-month Telephone Interview and Clinic Visit (N=3007 participants)
  • Baseline Telephone Screen and Clinic Visit (N=3026 participants)
Radiograph Images
  • 84-month PA and Lateral View Radiographs (N=1974 participants)
  • 60-month Full-limb View Radiographs (N=2115 participants)
  • 60-month PA and Lateral View Radiographs (N=3987 knees / 2118 participants)
  • 30-month PA and Lateral View Radiographs (N=5138 knees / 2655 participants)
  • 15-month PA and Lateral View Radiographs (N=577 knees / 293 participants)
  • Baseline Full-limb View Radiographs (N=3017 participants)
  • Baseline PA and Lateral View Radiographs (N=5956 knees / 3021 participants)
Radiograph Assessments
  • Longitudinal Baseline to 84-month PA and Lateral Knee Radiograph Assessments (N=6052 knees / 3026 participants) - includes Baseline and 60-month Full-limb (Hip-Knee-Ankle) Mechanical Alignment Assessments (N=6042 left/right sides / 3021 participants)
MR Images
  • 84-month MR Images (N=2763 knees/ 1517 participants)
  • 60-month MR Images (N=3036 knees / 1654 participants)
  • 30-month MR Images (N=4245 knees / 2225 participants)
  • 15-month MR Images (N=820 knees / 575 participants)
  • Baseline MR Images (N=5035 knees / 2600 participants)
MRI Assessments (WORMS)
  • 60-month to 84-month (N=1185 knees) (not available for release)
  • Baseline to 15-month Incident Knee Symptoms Cases and Controls (N= 415 knees)
  • Baseline to 30-month Subset of Knees with Baseline OA (N= 598 knees)
  • Baseline to 30-month Incident Radiographic OA Cases and Controls (N= 444 knees)
Outcomes Data
  • Outcomes: Baseline to 60-month Knee and Hip Replacements and Baseline to 84-month X-ray and Death Outcomes
What's New
MOST Public Data Release
The following datasets and images are now available:
  • 84-month Follow-up Clinical Data: Telephone Interview and Clinic Visit
  • 84-month Outcomes (x-ray and death only)
  • 84-month Reading Images
  • 60-month Full Limb Radiograph Assessments
  • 60-month Full Limb X-ray Images
Obtaining Data
To obtain data and images, send us your request and a signed Data Use Agreement.
See Data & Documentation and
Steps to obtaining data and images.

To collaborate with MOST investigators, submit an Analysis Proposal Form.
See Publications.
Data Use
MOST Online is intended as a means to learn about and obtain data and images collected in the Multicenter Osteoarthritis Study.

Site visitors imply understanding of intended uses of the research data and agree not to use the materials for any other purpose.
Website Requirements
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Multicenter Osteoarthritis Study knee OA example image