The company said its third-quarter revenue would probably be about $13.5 million.
National Health said that third-quarter revenue included about $3.5 million in such claims.
Its stock fell 22 percent in a day last month after the company said third-quarter revenue would grow less than expected.
Third-quarter revenue rose 21.8 percent, to $1.1 billion, from $903.1 million a year earlier.
The company announced late Friday that its third-quarter revenue would be poor.
Oxford said third-quarter revenues rose 31 percent, to $1.06 billion.
Third-quarter revenue was largely unchanged from 1988, at about $1.5 billion.
Third-quarter revenue rose 2.6 percent, to $278 million, up from the $271 million for the period last year.
Analysts said those prices are certain to translate into higher third-quarter revenues for most of the industry.
Legent said it now expected third-quarter revenues of about $99 million.