When speech is the aim of a study, it is difficult to encompass all aspects that may affect the outcome. Type of breathing, together with time of history, the severity of allergy, and frequency of crises; hypertrophy of pharyngeal tonsils and/or adenoid and the degree of hypertrophy; development of eating habits and the duration, frequency, and intensity of harmful habits; facial profile, strength and mobility of the facial muscles; development of hearing, auditory condition at the time of testing, and auditory processing; dental occlusion and craniofacial growth; and even the level of stimulation received during development should all be considered as so that the study’s results are more comprehensive.