🤖 AI Summary
Conventional generalized estimating equations (GEE) suffer from low estimation efficiency in small-to-moderate samples when analyzing pure-tone audiometry data, where complex within-cluster correlation structures—particularly interaural dependence—violate standard working correlation assumptions.
Method: This paper introduces a novel second-order GEE framework that jointly estimates regression coefficients and correlation structure parameters—specifically modeling interaural correlation parametrically—thereby improving statistical efficiency for ear-level covariate effects, especially under moderate-to-strong within-cluster dependence.
Contribution/Results: Simulation studies and analysis of real data from the Conservation of Hearing Study demonstrate that the proposed method achieves superior efficiency gains for ear-level exposure effect estimation compared to independence-, exchangeable-, and unstructured-GEE approaches. It robustly identifies a statistically significant association between dietary adherence and hearing loss. The core innovation lies in establishing an estimable and interpretable correlation structure modeling framework, advancing precise analysis of high-dimensional repeated-measures data in auditory epidemiology.
📝 Abstract
Due to the nature of pure-tone audiometry test, hearing loss data often has a complicated correlation structure. Generalized estimating equation (GEE) is commonly used to investigate the association between exposures and hearing loss, because it is robust to misspecification of the correlation matrix. However, this robustness typically entails a moderate loss of estimation efficiency in finite samples. This paper proposes to model the correlation coefficients and use second-order generalized estimating equations to estimate the correlation parameters. In simulation studies, we assessed the finite sample performance of our proposed method and compared it with other methods, such as GEE with independent, exchangeable and unstructured correlation structures. Our method achieves an efficiency gain which is larger for the coefficients of the covariates corresponding to the within-cluster variation (e.g., ear-level covariates) than the coefficients of cluster-level covariates. The efficiency gain is also more pronounced when the within-cluster correlations are moderate to strong, or when comparing to GEE with an unstructured correlation structure. As a real-world example, we applied the proposed method to data from the Audiology Assessment Arm of the Conservation of Hearing Study, and studied the association between a dietary adherence score and hearing loss.