Validation of self-reported occupational noise exposure in participants of a French case–control study on acoustic neuroma

Objectives To validate self-reported occupational loud noise exposure against expert evaluation of noise levels in a French case–control study on acoustic neuroma and to estimate the impact of exposure misclassification on risk estimation. Methods Noise levels were evaluated in 1006 jobs held by 111 cases and 217 population controls by an expert. Case–control differences in self-reporting were analyzed with logistic models. Sensitivity, specificity, positive and negative predictive values, and observed agreement of the self-reports were computed relative to the expert evaluation. They were used to calibrate the odds ratio (OR) between lifetime ever occupational loud noise exposure and the risk of acoustic neuroma, without adjustment for measurement error of the expert assessments. Results Cases reported noise levels in individual jobs closer to the expert assessment than controls, but the case–control difference was small for lifetime exposures. For expert-rated exposure of 80 dB(A), reporting of individual jobs by cases was more sensitive (54% in cases, 37% in controls), whereas specificity (91% in cases, 93% in controls) and observed agreement (82% in cases, 81% in controls) were similar. When lifetime exposure was considered, sensitivity increased (76% in cases, 65% in controls), while cases specificity decreased (84%). When these values were used to calibrate self-reports for exposure misclassification compared to expert evaluation at 80 dB(A), the crude OR of 1.7 was reduced to 1.3. Conclusions Despite the relatively accurate reporting of loud noise, the impact of the calibration on the OR was non-negligible.