You can assess voice transmission by palpation (tactile fremitus) and auscultation (vocal resonance)
Have the patient repeat 1, 2, 3. Feel the chest for tactile fremitus and listen for vocal resonance. Note the intensity, symmetry and quality of pitch.
Increased: Any situation where bronchial breathing is heard the sounds become loud, sharp and distinct bronchophony . In extreme situations, the whispered words come clearly and distinctly whispering pectoriloquy .
Over normal lungs the whisper will be muffled and not clearly heard.
Decreased: A quantitative decrease in voice transmission could be due to any other form of lung or pleural disease.
Qualitative alteration: A qualitative alteration of voice transmission is noted over consolidation and along the upper margin of pleural effusion egophony . The sound is like a nasal twang or goat bleating.
Asymmetrical voice transmission: Asymmetrical voice transmission points to disease on one side.
There was decreased voice transmission over the area of dullness, however along the upper limit of dullness egophony was elicited. That would favor a pleural effusion.