However, a causal relationship has not yet been definitively proven. The overall prevalence of dysphonia in children ranges from 3.9% - 23.4%, most commonly affecting children between the ages of 8 - 14. Among the elderly, dysphonia is associated with both naturally occurring anatomical and physiological changes as well as higher rates of pathological conditions. The point prevalence of dysphonia among the elderly is 29%. Findings regarding the prevalence of geriatric dysphonia in the general population are very variable, ranging from 4 - 29.1%. This variability is likely due to different methodology used in obtaining information from participants. The most common laryngeal diagnoses among the elderly are polyps, laryngopharyngeal reflux, muscle tension dysphonia, vocal fold paresis or paralysis, vocal fold mass, glottic insufficiency, malignant lesions, and neurologic conditions affecting the larynx. References
External links

ASHA: Voice Disorders
ASHA: Clinical Topics - Voice Disorders Overview
Barbiturate dependence develops with regular use of barbiturates. This in turn may lead to a need for increasing doses of the drug to get the original desired pharmacological or therapeutic effect. Barbiturate use can lead to both addiction and physical dependence, and as such they have a high potential for excess or non-medical use, however, it does not affect all users. Management of barbiturate dependence involves considering the affected persons age, comorbidity and the pharmacological pathways of barbiturates.Psychological addiction to barbiturates can develop quickly. The patients will then have a strong desire to take any barbiturate-like drug. The chronic use of barbiturates leads to moderate degradation of the personality with narrowing of interests, passivity and loss of volition. The somatic signs include hypomimia, problems articulating, weakening of reflexes, and ataxia.The GABAA receptor, one of barbiturates main sites of action, is thought to play a pivotal role in the development of tolerance to and dependence on barbiturates, as well as the euphoric "high" that results from their use. The mechanism by which barbiturate tolerance develops is believed to be different from that of ethanol or benzodiazepines, even though these drugs have been shown to exhibit cross-tolerance with each other and poly drug administration of barbiturates and alcohol used to be common. The management of a physical dependence on barbiturates is stabilisation on the long-acting barbiturate phenobarbital followed by a  gradual titration down of dose. People who use barbiturates tend to prefer rapid-acting barbiturates (amobarbital, pentobarbital, secobarbital) rather than long-acting barbiturates (barbital, phenobarbital).