The Osteoarthritis Initiative

a multi-center, four-year 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 11/02/2009

Clinical (download data from OAIOnline)	Baseline questionnaire and exam data for entire cohort (4,796 participants) (Nov 2008) 12-month follow-up questionnaire and exam data for entire cohort (Nov 2008) 18-month questionnaire data for subset of progression cohort participants (288 participants) (May 2009) 24-month follow-up questionnaire and exam data for entire cohort (May 2009) 30-month questionnaire data for subset of progression cohort participants (494 participants) (May 2009)
Biospecimens (refer to application guidelines on OAI Online; application deadlines: January 15, May 15, September 15)	Baseline serum, plasma, urine, and DNA for entire cohort (4,796 participants) (Jan 2009) 12-month serum, plasma, and urine for entire cohort (Jan 2009) 24-month serum, plasma, and urine for entire cohort (Jan 2009)
Images (refer to guidelines on OAI Online for requesting images from OAI Coordinating Center)	Baseline X-ray and MRI images (including thigh MRIs) for entire cohort (4,796 participants) (Nov 2008) 12-month X-ray and MRI images for entire cohort (Nov 2008) 18-month MRI images for subset of progression cohort participants (287 participants) (Nov 2007) 24-month X-ray and MRI images (including thigh MRIs) for entire cohort (May 2009) 24-month (and corresponding baseline and 12-month) X-ray and MRI images for samples of 200 participants (incidence and progression cohort) and 160 participants (progression cohort only) (May 2009) 30-month MRI images for subset of progression cohort participants (483 participants) (May 2009) New and replacement images (May 2009)
Image Assessments (download data from OAIOnline)	Semi-quantitative (K-L grade, IRFs) reading of paired baseline/follow-up knee X-rays (baseline, l2-month, 24-month, 36-month; various subsets of progression cohort) (Nov 2009) NEW DATA AVAILABLE! Quantitative joint space width from paired baseline/follow-up knee X-rays (baseline, l2-month, 24-month; various subsets of progression cohort) (Nov 2009) REVISED and NEW DATA AVAILABLE! Quantitative cartilage and bone morphology from paired baseline/follow-up knee MRIs (baseline, l2-month, 24-month; various subsets of progression cohort; various vendors) (Nov 2009) NEW DATA AVAILABLE! Quantitative knee alignment and lower limb geometry from full-limb X-rays (12-month; subset of progression cohort) (Feb 2009)

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.