Psychophysical uncertainty estimates for real ear attenuation at threshold measurements in naieve subjects

摘要

The International Standards Organization (ISO) TC43 SC1 has directed the working groups to use the“Guide to the expression of Uncertainty in Measurement” (GUM) in the development of new acousticalstandards. In light of this resolution, Working Group 17 on hearing protection has added an annex to aproposed standard ISO4869-7 describing a subject fit method for estimation of noise reduction. Data fromtwo laboratories, NIOSH Pittsburgh Research Lab and Howard Leight Industries were analyzed to examinethe within-test variance and between-test variance when subjects were tested using a Bekesy trackingparadigm. The NIOSH data demonstrated that the within-test variance, calculated from the reversals of theBekesy tracks did not agree with the between-test variability of the subjects’ repeated measures. This resultprompted a revision of the testing software to determine the within-test variance from the midpoint of theBekesy tracks. The revised software has been installed at both NIOSH PRL and Howard Leight facilities.This paper will compare the within-test and between-test variances determined with reversal levels and themidpoints from these two labs. The variability has been modeled with a simulated subject and Monte Carlotechniques.