Читать книгу Randomised Clinical Trials - David Machin - Страница 34

Brandes, Vastola, Basso, et al. (2003) describe a study comparing radiotherapy alone (Group A), radiotherapy and the combination of procarbazine, lomustine and vincristine (Group B) and radiotherapy with temozolomide (Group C) in 79 elderly patients with glioblastoma. The authors’ state:

The first group (Group A) was enrolled in the period from March 1993 to August 1995 … . The second group (Group B) was enrolled from September 1995 to September 1997 … . The third group (Group C) was enrolled from September 1997 to August 2000 and … .

The authors conclude:

Overall survival was better in Group C compared with Group A (14.9 months v 11.2 months, P = 0.002), but there was no statistical differences found between Groups A and B or between Groups B and C.

However, since patients have not been randomised to groups, one cannot be sure that the differences (and lack of differences) truly reflect the relative efficacy of the three treatments concerned. This type of design should be avoided if at all possible.