21.   At the report stage it may prove difficult to summarize the random sample of histories in a useful way.

22.   Because these comparisons were only among patients, the external validity was poor since patients are not a random sample of the general population.

23.   Although they looked at people in a variety of jobs with a range of income and education, she said, they did not use a random sample.

24.   And it would conduct a random nationwide sample to check for accuracy.

25.   And The Times sued the city last fall, seeking the names and addresses of those leaving welfare so it could create a random sample for a scientific survey.

26.   And the last would be a random nationwide sample to check for accuracy.

27.   A random sample of telephone numbers in Stark County was provided by Survey Sampling Inc. of Fairfield, Conn.

28.   But a spokeswoman for Rep. Ed Pastor, D-Ariz., the lone Democrat in the Arizona delegation, cautioned that the calls hardly constituted a random sample.

29.   But a random sample of Celtics voters indicate support for the union.

30.   By giving equipment and Internet access to everyone in a random sample, they could guarantee surveys would be representative of the entire population.