The Speech Detection Threshold is the weakest intensity at which your child demonstrates awareness that a sound is present, when that sound is speech. This threshold usually corresponds with your child's best hearing threshold for sounds at any frequency.
The Speech Reception Threshold is the weakest intensity at which your child can recognize familiar words, either by repeating them or by pointing to pictures as they are named. The Speech Reception Threshold usually corresponds with your child's average hearing thresholds across the audiometric frequencies.
The Speech Discrimination Score or Word Recognition Score is the percentage of one-syllable words your child can identify (without visual cues), when the words are heard at a loudness level that is comfortable for your child.
Speech discrimination ability usually is quite good in children with conductive hearing loss, as long as the words are presented at a level that is intense enough to overcome the loss of volume from outer or middle ear dysfunction. If your child has sensorineural hearing loss, however, speech discrimination ability may be reduced even when the words are presented at intense levels or if background noise is present.