Voice and speech disorders can be assessed through subjective perceptual measures or objective indices, such as the Acoustic Voice Quality Index (AVQI) or the Acoustic Breathiness Index (ABI). These objective measures reduce diagnostic variability by eliminating subjective evaluations. However, the impact of room acoustics on their robustness for therapy monitoring remains unclear. In this contribution, reverberation times, impulse responses, and background noise were recorded and analyzed in conjunction with speech samples using statistical models to evaluate their influence. Results indicate that room acoustics significantly affect AVQI and ABI, particularly for non-pathological voices and with distant microphones. For reliable therapeutic use, standardized measurement environments or robust analysis methods are essential. Optimized recording conditions with source-proximate microphones enhance accuracy, advancing objective voice quality assessments and evidence-based speech therapy.