Quality control chart method for analyzing PEF variability in occupational asthma.

Background: Asthma is the most common occupational respiratory disorder in the industrialized world. In this research we investigated the effectiveness of quality control chart as a method to explore the work-relatedness of asthma using peak expiratory flow (PEF) as the variable of interest.

Method: PEF measurements were recorded from several workers suspected of having occupational asthma.

Control chart for monitoring occupational asthma.

Introduction: Work-related asthma has become the most prevalent occupational respiratory disease in the developed world. Occupational asthma is thought to affect 5%-10% of people worldwide. The first step in the diagnosis of occupational asthma is to establish work-relatedness.