Key words	Vocal effort	Vocal load(ing)	Vocal fatigue
Vocal symptom/deficit			34
Prolonged voicing time	4	14	27
Increased effort			19
Vocal loading		28	11
Tiring of voice			11
Neck strap muscle involvement (throat or cervical muscle tension)	3	2	9
Laryngeal/vocal discomfort			9
Physiological condition			9
Improvement after vocal rest			7
Reduced pitch range and flexibility			7
Reduced control of voice quality			6
Changes in intensity			4
Weak voice			4
Increased risk for voice disorders			3
Negative vocal adaptation			3
Vocal loudness change	23	11
Raise in F0	11
Distance to the interlocutor	9
Strain in voicing	6	6
Increase sound level (loudness)	6	4
Related with background noise	5	6
Increase first format frequency	5
Increase subglottal (tracheal) pressure	5
Perceived effort during phonation	2	5
Mood induction	2	2
Pitch changes		14
Professional related		10
Poor room acoustics		9
Lack/increase of vibration		7
Vocal fatigue		7
Aerodynamics		6
Air quality		6
More common in women		6
Noise		6
Self-assessed		6
Vocal demand		6
Acoustic analysis		5
Voice quality affected		5
Disorder		4
Singing/theater		4
Stroboscopy		4
Dysphonia		3
Hoarseness		3
Inflammation		3
Nodules		3
Nonhabitual voice use		3