Table 1.

Physiological and pathological factors associated with the voice perturbation and disorders; information is modified from [5]

Factors	Prevalence	Literature source
Gender	• Higher prevalence of voice disorders in women	6
Ageing	• Increasing prevalence of laryngeal disorders in elderly (> 65 years old)	7
Puberty	• Prevalent alterations in voice parameters such as voice pitch	8
Family history of voice disorders	• Prevalent family history of hoarseness and voice disorders studied in certain professional groups such as teachers (P = 0.0001)	9
Professional occupation	• Voice perturbation and disorders are more prevalent in certain professional groups such as teachers, call centre workers and singers	10
Toxic environment	• Higher risk of voice perturbation and laryngeal disorder in (both active and passive) tobacco smokers	11, 12