Table 2.

Limitations of older antibiotic study design in acute exacerbations of COPD

Small number of enrolled patients limits study power

Enrollment of patients with mild COPD or normal lung function with high rates of recovery diminishes perceived efficacy of antibiotics

No assessment of speed of recovery

Use of end points 3 weeks post treatment when spontaneous recovery may have occurred

Lack of long-term follow up and therefore no assessment of time to next exacerbation

No evaluation of concurrent medication likely to affect clinical outcome, allowing potential bias