title: Between- and within-observer agreement for expert judgment of peak flow graphs from a working population.
abstract: Expert judgment of peak flow-time graphs provides an important tool to detect occupational asthma. This technique has mainly been used in clinics to evaluate reversible airflow obstruction and to assess potential work-related patterns. The reproducibility of this technique in an open working population is unknown. Agreement between and within nine experts was studied using peak flow-time graphs of 49 potato-processing workers. All graphs were classified into four categories by the nine experts, while seven experts read ten graphs at two occasions. Thirty-four graphs (69%) were classified as "no airway obstruction" while four graphs (8%) showed "work-related airway obstruction." There was only slight agreement between the nine experts; mean Cohen's kappa (kappa) was 0.19. Agreement within experts was moderate; mean kappa was 0.47 for judging graphs twice. Our results suggest that in a "healthy" working population, judgment of peak flow graphs is not a favorable method for detection of airway obstruction. If this technique is applied in epidemiological studies, judgment of the graphs should be done by more than one expert.
authors.affiliation: Wageningen Agricultural University, The Netherlands.
authors.forename: J P
authors.initials: JP
authors.lastname: Zock
authors.forename: D
authors.initials: D
authors.lastname: Brederode
authors.forename: D
authors.initials: D
authors.lastname: Heederik
mesh_terms: D000328:Adult; D001249:Asthma / Q000175:diagnosis* / Q000503:physiopathology; D005524:Food Technology; D006801:Humans; D008875:Middle Aged; D009426:Netherlands; D015588:Observer Variation; D009784:Occupational Diseases / Q000175:diagnosis* / Q000503:physiopathology; D010366:Peak Expiratory Flow Rate; D015203:Reproducibility of Results; D011198:Solanum tuberosum; D013997:Time Factors