From "Improving General Practice Care of Patients with Asthma or Chronic Obstructive Pulmonary Disease: Evaluation of a Quality System" Effective Clinical Practice, January/February 2000. 3:16-24.
Figure 2. Comparison of intervention and control practices before and after introduction of the quality system. The median rates of compliance with the guidelines are shown. P values are for the before-after within group difference. PEFR = peak expiratory flow rate.>