| Speech sound | Auditory-perceptual and segmental characteristics | Production accuracy/percentage of errors | 30 | Percentage of consonants correct (PCC), the number of articulation errors, presence of consonant errors, correctness, proportion of articulatory errors | 2, 6, 8, 10, 11, 12, 15, 16, 18, 19, 24, 25, 26, 27, 29, 30, 35, 37, 40, 41, 42, 44, 45, 48, 49, 51, 53, 57, 59, 62 |
| Type of error | 4 | Type of error | 27, 41, 56, 69 |
| Error patterns | 9 | Phonological error patterns (phonological process) | 14, 15, 26, 27, 35, 41, 48, 49, 53 |
| Phonetic inventories | 1 | Phonetic inventories | 62 |
| Phonological features | 2 | Percentage of feature retention, distinctive feature retention | 26, 51 |
| Auditory-perceptual and suprasegmental characteristics | Phonation | 1 | Voice onset time | 52 |
| Rate | 2 | Speech rate, articulatory rate | 38, 42 |
| Pause | 1 | Length and frequency of pause, inappropriate pause | 38 |
| Disfluency | 2 | Disfluency type, disfluency score, incidence ratio of disfluency, distribution of disfluencies at syntactic location | 1, 59 |
| Acoustic-phonetic features | 6 | Fundamental frequency (Fo), highest Fo (Fhi), lowest Fo (Flo), semitone frequency range (PFR), jitter, shimmer, noise-to-harmonics ratio (NHR), voice turbulence index (VTI), soft phonation index (SPI), variation of Fo (vFo), variation of amplitude (vAm), mean dB, dB range, pitch, loudness, voice quality, length of friction intervals, breathing intervals, central moment, skewness, kurtosis, a center of gravity, variance, F1, F2, vowel space area, slope and amount of change of formant (F1, F2) | 3, 5, 22, 24, 46, 61 |
| Other factors | Whole-word measurements | 2 | Phonological mean length of utterance (PMLU), weighted phonological mean length of utterance (PMLU-W), proportion of whole-word proximity (PWP), proportion of whole-word correctness (PWC) | 30, 50 |
| Consistency/variation | 6 | Consistency, variation of articulation (articulatory variability), variation/inconsistency of articulatory error | 7, 9, 10, 16, 29, 53 |
| Intelligibility | 4 | Speech intelligibility | 5, 11, 42, 44 |
| Acceptability | 1 | Speech acceptability | 11 |
| Structure/function | Oral motor structure and function | 2 | Facial symmetry (resting symmetry and symmetry of voluntary movement), external structure, nonverbal movement, diadochokinesis (DDK), alternative motion rate (AMR), sequential motion rate (SMR) | 22, 24 |
| Speech perception | 2 | Speech perception | 6, 60 |
| Language | Vocabulary | 9 | Receptive vocabulary, expressive vocabulary | 2, 6, 19, 25, 37, 39, 40, 53, 57 |
| Reading | 1 | Reading skill (word recognition) | 36 |
| Writing | 1 | Writing fluency and content scoring | 45 |
| Comprehension | 1 | Story comprehension | 63 |
| Cognition | Phonological process | Phonological memory | 14 | Word repetition (accuracy, reaction time), sentence repetition accuracy, non-word repetition (accuracy, variation, reaction time, type of errors, percentage of error types), digit span forward/backward (recall, retrieval scores, sequencing scores), rapid automatized naming, forward/reverse pointing of word, priming task result (retrieval distractor, sequencing distractor) | 7, 13, 17, 23, 25, 28, 31, 33, 39, 40, 43, 55, 56, 63 |
| Phonological representation | 3 | Score and reaction time on the phonological representation judgment task, retrieval accuracy, score and reaction time on internal awareness of phonological representation task | 2, 20, 33 |
| Phonological awareness | 9 | Phonological awareness | 4, 20, 21, 31, 36, 39, 45, 55, 57 |
| Intelligence | 1 | Nonverbal intelligence | 25 |
| Memory | 1 | Visual sequential memory, spatial memory, word order memory | 43 |
| Learning ability | 1 | Accuracy and implicit learning ability on sequence learning task | 21 |
| Others | Internal characteristics | 2 | Communication attitude, self-esteem, self-efficacy | 18, 58 |
| Sustained attention | 1 | Score and response time on visual and auditory sustained attention task | 19 |
| Foreign language vocabulary | 1 | English vocabulary knowledge, English vocabulary learning score | 25 |
| Risk factors | 1 | Language and gross motor development, gender and early development, otitis media with effusion, socioeconomic status, family history | 54 |