Precision of longitudinal spirometric measurements in workplace screening - monitoring and interpretation.
Hnizdo-E; Yu-L; Freyder-L; Attfield-M; Lefante-J; Glindmeyer-HW
Abstracts of the 10th International Conference on Occupational Respiratory Diseases, April 19-22, 2005, Beijing, China. Geneva: International Labour Office, 2005 Apr; :265
The efficacy of decision-making based on longitudinal spirometric measurements in workplace screening depends critically on the precision of the available data. We describe and investigate two statistical methods - a pairwise estimate of within-person standard deviation Sp and the reliability coefficient G -for use in monitoring of precision of repeated measurements of forced expiratory volume in one second (FEV 1). We also investigate the effect of data precision on the detectable excess rate of decline in FEV1. We "monitored" retrospectively on a yearly basis the magnitude of Sp and G in eleven workplace-based spirometric monitoring programs conducted from 1987 to 2001 on 12,729 workers. The plant-specific means of Sp (range, 122-166 ml) and of G (range, 0.88-0.95) correlated well with the plant-specific within-person standard deviation Sw (range, 130-177 ml) estimated from all longitudinal data (for Spr = 0.90; for G r=0.68). The precision of the longitudinal FEV1 in individual programs determined the detectable excess rate of decline in FEV1. In conclusion, monitoring of longitudinal data precision allows that data precision can be improved or maintained at levels that allow rapid decliners to be identified at an earlier age and attaches a measure of precision to the data on which decision-making is based.
Spirometry; Workers; Workplace-monitoring; Monitors; Monitoring-systems; Statistical-analysis; Surveillance
Abstract; Conference/Symposia Proceedings
Abstracts of the 10th International Conference on Occupational Respiratory Diseases, April 19-22, 2005, Beijing, China