Title: Functional Data Analysis in Hearing Research: A Clinical Research Perspective

Music City Center 

In a hearing clinical trial comparing Tinnitus patients to a control group, noise exposure was recorded every 3.75 minutes over 7 days. Tinnitus is the perception of sound in the ears or head without an external source. We present an application-driven approach for time series denoising and group comparisons in analyzing sound exposure patterns between the two groups. Instead of traditional two-sample comparison methods, functional data analysis (FDA) was employed. Noise exposure sequences were decomposed into group-specific mean and residual functions, preserving both group-level trends and individual variations. This FDA-based denoising procedure reduced random fluctuations, enhancing the detection of systematic group differences. For statistical inference, a basis function-based simultaneous confidence band was constructed using the denoised sequences. Simultaneous confidence band results closely aligned with the pointwise Wilcoxon test adjusted by the B-H procedure, revealing the most pronounced differences in different times of the day. This approach demonstrates the effectiveness of functional data analysis in time series denoising and structured group comparisons.

Tinnitus

Functional Data Analysis

Clinical Research

Time Series

Intensive Longitudinal Data 

ENAR