31.   Patients in our study fared better with NIPPV, and in the conventional treatment group some patients had to switch to NIPPV.

32.   The three treatment groups were well matched at baseline for age, sex, and disease severity.

33.   When analyses were repeated with both active treatment groups combined, there was no significant difference from placebo in the mean improvement of any parameter.

34.   The numbers withdrawn were similar in each treatment group.

35.   Furthermore, baseline comparability of treatment groups was not established.

36.   It is important to establish baseline comparability of treatment groups in terms of disease severity in such an analysis but this issue was not addressed.

37.   Nonetheless, stroke was observed only in patients in the treatment group in the studies from Philadelphia.

38.   But by the end of five years, their symptoms began returning so that the two treatment groups were about equal.

39.   The experiences of the control group provide a natural benchmark against which to judge how the treatment group would have fared absent Progresa.

40.   The maximum number of new events per patient was two in the treatment group and six in the control group.