Quality of published clinical trials on asthma.
The quality of 287 clinical trials on asthma treatment published between 1984 and 1997 is described in this article, using a scale adding to a maximum of 14 points. The mean quality score was 8.60 (standard deviation 1.55). Quality improved throughout time from 8.17 +/- 1.40 before 1989 until 9.55 +/- 1.66 after 1992. Several methodological issues were associated with higher quality, namely parallel design, longer length of the follow-up, complete description of the exclusion criteria, description of the initial and ending recruitment dates, higher sample size, explicit sample size calculation, blinding, full description of randomization, intention-to-treat analysis, full description of the intervention, and evaluation of bias. The higher statistical significance, however, was not associated with higher clinical trial quality.
Quiñones
Dolores
D
Division of Preventive Medicine and Public Health, University of Cantabria School of Medicine, Santander, Spain.
Llorca
Javier
J
Dierssen
Trinidad
T
Delgado-Rodríguez
Miguel
M
D001249:Asthma / Q000628:therapy*; D006801:Humans; D011643:Publishing / Q000592:standards; D016032:Randomized Controlled Trials as Topic / Q000592:standards* / Q000706:statistics & numerical data; D012107:Research Design; D013223:Statistics as Topic