The Osteoarthritis Initiative

a multi-center observational study of men and women

The OAI is a nationwide research study, sponsored by the National Institutes of Health (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.

OAIOnline is the name for this website, which provides access to the Osteoarthritis Initiative (OAI) study documentation and data.

Data News
1-2-3 Data. Three quick steps to download the clinical data.

What's available as of Dec 13, 2013

Clinical
(download data from OAIOnline)
  • 84-month follow-up questionnaire data for entire cohort (Dec 2013)

  • NEW DATA AVAILABLE!
  • 48-month accelerometry for subset of cohort (2,712 participants) (Dec 2013)

  • NEW DATA AVAILABLE!
  • 72-month follow-up questionnaire and exam data for entire cohort (Feb 2013)
  • 60-month follow-up questionnaire data for entire cohort (April 2012)
  • 48-month follow-up questionnaire and exam data for entire cohort (Oct 2011)
  • 36-month follow-up questionnaire and exam data for entire cohort (March 2010)
  • 30-month questionnaire data for subset of progression cohort participants
    (494 participants) (May 2009)
  • 24-month follow-up questionnaire and exam data for entire cohort (May 2009)
  • 18-month questionnaire data for subset of progression cohort participants
    (288 participants) (May 2009)
  • 12-month follow-up questionnaire and exam data for entire cohort (Nov 2008)
  • Baseline questionnaire and exam data for entire cohort (4,796 participants)
    (Nov 2008)
Biospecimens
(refer to application guidelines on OAI Online; application deadlines: January 15, May 15, September 15)
  • 72-month serum, plasma, and urine for entire cohort (Feb 2013)
  • 48-month serum, plasma, and urine for entire cohort (Oct 2011)
  • 36-month serum, plasma, and urine for entire cohort (March 2010)
  • 24-month serum, plasma, and urine for entire cohort (Jan 2009)
  • 12-month serum, plasma, and urine for entire cohort (Jan 2009)
  • Baseline serum, plasma, urine, and DNA for entire cohort
    (4,796 participants) (Jan 2009)
Images
(refer to guidelines on OAI Online for requesting images from OAI Coordinating Center)
  • 72-month X-ray and MRI images for entire cohort (Feb 2013)
  • 48-month X-ray and MRI images for entire cohort (Oct 2011)
  • 36-month X-ray and MRI images for entire cohort (March 2010)
  • 30-month MRI images for subset of progression cohort participants
    (483 participants) (May 2009)
  • 24-month X-ray and MRI images for entire cohort (May 2009)
  • 18-month MRI images for subset of progression cohort participants
    (287 participants) (Nov 2007)
  • 12-month X-ray and MRI images for entire cohort (Nov 2008)
  • Baseline X-ray and MRI images for entire cohort
    (4,796 participants) (Nov 2008)
  • New and replacement images
    (May 2009)
Image Assessments
(download data from OAIOnline)
  • Imaging Inventory for Study Planning database (4,796 participants)
    (Dec 2013)

  • NEW DATA AVAILABLE!
  • Quantitative joint space width from longitudinal sets of knee X-rays (baseline, l2-month, 24-month, 36-month, 48-month; 3,154 participants) (June 2013)
  • Semi-quantitative (K-L grade, IRFs) reading from longitudinal sets of knee X-rays (baseline, l2-month, 24-month, 36-month, 48-month; 4,491 participants) (June 2013)
  • Quantitative knee alignment and lower limb geometry from full-limb X-rays
    (12-month, 24-month, 36-month, 48-month; 3,475 participants) (June 2013)
  • Quantitative anatomic axis alignment (femoral-tibial angle) from knee X-rays
    (baseline; 3,112 participants)
    (June 2013)
  • Reliability readings for quantitative joint space width from longitudinal sets of knee X-rays (baseline, l2-month, 24-month, 36-month; 136 participants) (April 2012)
  • Reliability readings for semi-quantitative (K-L grade, IRFs) reading from longitudinal sets of knee X-rays (baseline, l2-month, 24-month, 36-month, 48-month; 149 participants) (April 2012)
  • Quantitative cartilage and bone morphology from longitudinal sets of MRIs (baseline, l2-month, 24-month, 48-month; subset of entire cohort; various vendors) (April 2012)
  • SQ whole organ score using both WORMS and BLOKS (baseline, 24-month, subset of progression cohort) (June 2011)
  • Manual cartilage segmentations (baseline, 12-month; subset of progression cohort) (June 2011)
Outcomes
(download data from OAIOnline)
  • Endpoint database for knee and hip replacements, x-ray outcomes, deaths (4,540 participants) (Dec 2013)

  • NEW AND REVISED DATA AVAILABLE!
OAIOnline Technical Requirements
OAIOnline is designed to work best with Internet Explorer 6+ and Adobe Acrobat Reader 5+. Firefox and Safari browsers will also work well. All the browsers mentioned above and Acrobat Reader are freely available.
Important: OAIOnline is intended as a means to learn about and retrieve the data collected in the Osteoarthritis Initiative. By using OAIOnline, users imply understanding of these intended uses and agree not to use the website or downloadable materials for any other purpose.
Create an account now!
You must have an account and accept the terms of a Data Use Agreement before you can download or explore clinical data. Please go to My Account and create a new account now.
New Features in Data & Documentation
Tutorial: Where do I begin? Try the clinical data tutorial which walks you through the variety of tools available on OAIOnline for touring and understanding the data.
Search/browse: Search/browse a database of categorized variable documentation displayed longitudinally with links to statistics, comments, and annotated data collection forms.
My Cart: Create a personal cart of variables of interest that can be used 1) to build a custom codebook able to be read offline, and 2) to filter downloadable datasets.
DataExplorer: Use DataExplorer to generate descriptive statistics: cross tabs, subsets, frequency distributions and more. Note this tool requires an account and acceptance of the terms of a Data Use Agreement.

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