BETWEEN-OBSERVER AND WITHIN-OBSERVER AGREEMENT FOR EXPERT JUDGMENT OFPEAK FLOW-GRAPHS FROM A WORKING POPULATION

Expert judgement of peak flow-time graphs provides a an important tool to detect occupational asthma. This technique has mainly been used in clinics to evaluate reversible airflow obstruction and to assess pote ntial work-related patterns. The reproducibility of this technique in an open working population is unknown. Agreement between and within ni ne experts was studied using peak flow-time graphs of 49 potato-proces sing workers, All graphs were classified into four categories by the n ine experts, while seven experts read ten graphs at two occasions, Thi rty-four graphs (69 %) were classified as ''no airway obstruction '' w hile four graphs (8 %) showed ''work-related airway obstruction. '' Th ere suns only slight agreement between the nine experts; mean Cohen's kappa (kappa) was 0.19. Agreement within experts was moderate; mean ka ppa was 0.47 for judging graphs twice. Our results suggest that in a ' 'healthy '' working population, judgement of peak flow, graphs is not a favorable method for detection of airway obstruction. If this techni que is applied in epidemiological studies, judgment of the graphs shou ld be done by more than one expert.