"... The OHSUMED test collection [osu,medline] is a set of 348,566 references 
from MEDLINE, the on-line medical information database, consisting of titles
and/or abstracts from 270 medical journals over a five-year period
(1987-1991). The available fields are title, abstract, MeSH indexing
terms, author, source, and publication type. The National Library of
Medicine has agreed to make the MEDLINE references in the test database
available for experimentation, restricted to the following conditions:

1. The data will not be used in any non-experimental clinical, library,
or other setting.

2. Any human users of the data will explicitly be told that the data is
incomplete and out-of-date.

The OHSUMED document collection was obtained by William Hersh
(hersh@OHSU.EDU) and colleagues for the experiments described in the
papers below:

Hersh WR, Buckley C, Leone TJ, Hickam DH, OHSUMED: An interactive
retrieval evaluation and new large test collection for research,
Proceedings of the 17th Annual ACM SIGIR Conference, 1994, 192-201.
Hersh WR, Hickam DH, Use of a multi-application computer workstation in
a clinical setting, Bulletin of the Medical Library Association, 1994,
82: 382-389. ..."