TABLE 1.

Data extracted from included papers: Study characteristics, aims, design, sample size, speech input processing measures, inclusion/exclusion criteria and results relevant to this review

Reference	Aim(s) of the study	Study design	Sample size	Input processing measure(s)	Inclusion criteria	Exclusion criteria/potential confounders considered	Results relevant to this review
Anderson et al. (2016)	To test if: (1) children with poorer PA skills will have impaired middle ear function; (2) children with poorer PA skills will have poorer speech production skills; and (3) a significant relationship between VP function and PA will be conditional to a significant relationship between PA and speech production and middle ear function	Retrospective cohort	30	PIPA (Dodd et al. 2000) Subtests Rhyme Awareness and Alliteration Awareness	5;0–6;0 years of age, Australian English only language, repaired CL/P, no history of central nervous system involvement, no sensorineural hearing loss, a complete data set in the database	Other diagnosed syndromes or medical conditions present	Rhyme awareness for cohort (SS between 7 and 13 within normal limits): mean SS = 7.43 (SD = 3.014, range = 3–13) Alliteration Awareness for cohort (SS between 7 and 13 within normal limits): mean SS = 9.23 (SD = 3.081, range = 4–15)
Baylis et al. (2008)	To examine the influence of speech sound perception skills, cognitive skills and implicit phonological learning ability on the articulation skills of children with VCFS and those with cleft palate or VPD	Case/control	13 (8 VCFS, 5 CP/VPD)	Minimal pair discrimination task with initial or final phoneme contrasts	VCFS group: confirmed diagnosis by genetic testing. CP/VPD group: non‐syndromic repaired cleft palate, submucous CP/VPD. All English first language	Children with clefts involving the lip and alveolus. CP/VPD group: no known learning disabilities, no other congenital anomalies or syndromes, no known behavioural or psychiatric conditions, no known language impairments, no oronasal fistulae at the time of the study	All three participants with CP/SMCP scored 98% on speech perception task compared with a group mean score of 91% for the group with VCFS
Collett et al. (2010)	To test the hypothesis that children with orofacial clefts would score lower than controls on measures of reading and closely related skills	Case/control	42 (cleft group), 43 (control group): ‘sound matching’ task only administered with 23 cases and 24 controls	Sound matching subtest of the CTOPP (Wagner et al. 1999)	5–7 years of age, enrolled in kindergarten through second grade, English first language	Known genetic or neurodevelopmental syndrome, visual or auditory impairments that would preclude participation, previously diagnosed learning disability, history of traumatic brain injury, out of home residential placement. Controls also excluded if any history of craniofacial anomaly	Sound matching task: children with clefts: mean SS = 10.9 (SD = 1.7, 95% CI = 8.7–10.5); children without clefts: mean SS = 10.6 (SD = 2.1, 95% CI = 9.7–11.5). Adjusted mean difference = 0.1 (95% CI = –1.1 to 1.3), p = 0.909
Finnegan (1974)	To compare speech sound discrimination skills of boys with and without a cleft palate. To determine if there is a difference in speech sound discrimination between boys with cleft palate with and without a history of middle ear pathology. To ascertain whether there is a difference in speech sound discrimination skills between boys with cleft palate with and without velopharyngeal incompetence	Case/control	16 (cleft group), 16 (non‐cleft group)	Speech Sound Discrimination Task 68‐F (Rudegeair and Kamil 1969)	Monolingual American English speakers controlled for regional dialect, normal intelligence, no significant deviation in oro‐pharyngeal structures other than surgical repair of the cleft, air conduction hearing threshold average < 2b dB in the better ear for frequencies 500, 1000 and 2000 Hz	Any history of abnormal middle ear pathology in the non‐cleft group	Total mean number of errors on discrimination task higher for cleft group (mean for cleft group = 3.347 (SD = 2.56), mean for non‐cleft group = 1.343 (SD = 1.06). Statistical evidence for effect of group on performance (p ≤ 0.01). Non‐cleft group better at discriminating between affricate and nasal manner classes (p < 0.05 and < 0.01 respectively). Non‐cleft group made no errors with /b/ versus /p/ contrasts, but for cleft group this contrast accounted for a quarter of their errors on voiced/voiceless contrasts. Both groups found voicing contrasts easier to discriminate than place of articulation
Lemos and Feniman (2010)	To verify the performance of children with cleft lip and palate in the SAAAT	Case/control	30 (cleft group), 25 (non‐cleft group)	SAAAT	Non‐cleft group: no cleft lip and palate or associated syndrome, no diagnosis of ADHD or use of medication associated with ADHD, peripheral hearing within normal limits, right‐handed, no diagnosis of any syndrome. Cleft group: CL/P, scheduled visit to the hospital in a 9‐month period, age 7 years at the time of the visit, additional inclusion criteria as per the non‐cleft group	None in addition to needing to meet the inclusion criteria	Evidence of a difference in performance between cleft and non‐cleft groups on ‘decreased vigilance’ domain of SAAAT, with the cleft group performing less well (p = 0.008). No statistical evidence for differences between groups in other domains of the test (inattention, impulsiveness, total number of errors)
Whitehill et al. (2003)	To determine whether children with CP and posterior articulation placement error patterns also demonstrated difficulty in the perception of anterior versus posterior place of articulation in comparison with control groups	Case control	10 (CP plus posterior articulation), 10 (CP with no posterior articulation) and 10 (non‐cleft controls)	Perception of place of articulation (t to k) along an acoustic continuum from synthetic stimuli	Children born with CP presenting with or without posterior placement of alveolar targets. No identified syndrome. Surgical palate closure between 12 and 18 months of age. No palatal fistula at time of testing. Normally developing children matched in age to the children with CP and with no history of speech, language, hearing or learning problems from parent report	As per inclusion criteria.	On an acoustic continuum, children with no CP and children with CP but no posterior speech errors identified 90% of stimuli on one side of identified phonemic boundary as /kh/ and 95% of stimuli on the other side as /th/. All children in these groups able to categorize stimuli into two clear groups. Children with CP and posterior speech errors identified 51–65% of all stimuli along the continuum as /kh/. No children in this group able to identify the stimuli appropriately

Note: ADHD, attention deficit hyperactivity disorder; CP, cleft palate; CL/P, cleft lip and/or palate; CTOPP, Comprehensive Test of Phonological Processing; PA, phonological awareness; PIPA, Primary Inventory of Phonological Awareness; SAAAT, Sustained Auditory Attention Ability Test; VCFS, velocardiofacial syndrome; VP, velopharyngeal; VPD, velopharyngeal dysfunction; SS, standard/scaled scores; SD, standard deviation; CI, confidence interval; and SMCP, submucous cleft palate.