[Efficiency of investigators in recruitment of patients for clinical trials: apropos of a multinational study]

Med Clin (Barc). 1998 Apr 25;110(14):521-3.
[Article in Spanish]


Background: Performance and efficiency in patient selection are essential for conducting clinical trials. Data on these are presented from a multinational trial.

Patients and methods: A randomized, double-blind, placebo-controlled, parallel-group study in asthma, with a screening phase followed after randomization by a treatment period, was selected. Number of patients screened and randomized by centre and country, centres achieving the minimum recruitment (> or = 10 patients randomized), and efficiency of investigators (randomized/screened x 100) were determined and compared.

Results: 564 patients, out of 836 screened, were randomized at 69 centres in 11 countries. Twenty-four centres (35%) randomized > or = 10 patients each, accounting for 70% (n = 395) of the total number recruited. Efficiency was significantly higher among these "high-performance" centres (81.4%; p < 0.001; OR, 4.7; CI 95%, 3.4-6.5) than in the remaining ones (48.1%). Five countries had > or = 2 "high-performance" centres. Efficiency was also significantly higher (p < 0.001) among those (370 randomized/455 screened, 82.1%) than in the remaining centres of the same countries (82/140; 58.6%; OR, 3.0; CI 95%, 2.7-4.7). A relevant number of centres (n = 17; 25%) randomized 0-1 patient (7 randomized/58 screened).

Conclusion: The analysis of patient selection in clinical trials showed that a minority of centres accounted for most of the patients recruited. Those are not only the most productive (more patients randomized) but also the more efficient (better quality of screening process).

Publication types

  • English Abstract
  • Multicenter Study

MeSH terms

  • Asthma / therapy
  • Double-Blind Method
  • Humans
  • Patient Selection*
  • Randomized Controlled Trials as Topic*