Introduction
Methods
Search Strategy and Quality Assessment
Database | Search terms | Limitations | Results |
---|---|---|---|
MEDLINE | (child* OR infant OR („child" [MESH]) OR („infant" [MESH])) AND ("fiberoptic endoscopic evaluation of swallowing" OR „flexible-endoscopic evaluation of swallowing “ OR „endoscopic assessment “ OR „endoscopic evaluation “)) AND (dysphagia OR swallow* OR „swallowing disorder" OR „swallowing dysfunction" OR „deglutition disorder" OR "feeding disorder" OR ("deglutition disorder [MESH])) | Human 2000–2021 English | 113 |
CINAHL | (children OR infant OR pediatric) AND ("fiberoptic endoscopic evaluation of swallowing" OR „flexible-endoscopic evaluation of swallowing “ OR „endoscopic assessment “ OR „endoscopic evaluation “) AND (dysphagia OR „swallowing disorder" OR „deglutition disorder") | Human 2000–2021 English | 31 (2 in addition to MEDLINE) |
Inclusion criteria | Exclusion criteria |
---|---|
Children 0–18 years. with suspected dysphagia | Adults or mixed sample with less than 90% < 18 years |
All diagnoses | Foreign body aspiration |
Original work Description of a FEES protocol with at least two of the following criteria: Diameter and/or type of endoscope Positioning of the child Anesthesia and/or nasal decongestion Food coloring | Reviews No description of a pediatric FEES protocol |
Inclusion and Exclusion Criteria
Risk of Bias and Quality Assessment
Study | Q1 | Q2 | Q3 | Q4 | Q5 | Q6 | Q7 | Q8 | Q9 | Q10 | Q11 | Q12 | Q13 | Q14 | Quality |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Armstrong et al. [12] | Y | N | Y | Y | N | NA | N | NA | NA | NA | N | NA | NA | N | Fair |
Averin et al. [13] | Y | Y | Y | Y | N | NA | N | NA | Y | N | N | NR | NA | N | Fair |
Beer et al. [27] | Y | Y | Y | Y | N | N | N | N | N | N | N | N | NA | N | Poor |
Da Silva et al. [21] | Y | Y | NR | Y | N | N | N | NA | NA | NA | N | NR | NA | N | Fair |
Hartnick et al. [28] | Y | N | NR | Y | N | N | N | NA | NA | NA | N | NR | NR | N | Poor |
Kamity et al. [14] | Y | Y | NR | Y | N | N | N | NA | NA | NA | N | NA | NA | N | Fair |
Leal et al. [22] | Y | Y | NR | Y | N | Y | N | NA | Y | N | Y | NR | NA | NA | Fair |
Leder et al. [23] | N | Y | NR | NR | N | N | N | N | Y | N | N | NA | NA | NA | Poor |
Leder & Karas [10] | Y | Y | N | N | N | N | NA | NA | NA | N | NA | NA | NA | NA | Poor |
Link et al. [11] | Y | Y | Y | Y | N | N | N | Y | Y | N | N | N | NA | N | Fair |
Marques et al. [15] | Y | Y | NR | Y | N | N | Y | NA | Y | NA | N | N | N | N | Fair |
Mills et al. [16] | Y | Y | Y | Y | N | N | N | NA | Y | N | N | N | NA | N | Fair |
Pavithran et al. [24] | Y | Y | NR | Y | N | N | N | NA | NA | NA | N | NA | NA | N | Fair |
Richter et al. [25] | Y | Y | Y | Y | N | NA | CD | NA | Y | NA | N | NR | NR | N | Fair |
Sitton et al. [29] | Y | Y | Y | Y | N | Y | NA | Y | N | CD | N | NR | Y | N | Fair |
Suiter et al. [30] | Y | Y | NR | NR | N | N | N | Y | Y | N | N | N | NA | N | Poor |
Suskind et al. [17] | Y | Y | NR | N | N | N | N | N | N | NR | N | NR | NR | N | Poor |
Suterwala et al. [18] | Y | Y | NR | Y | N | N | N | NA | NA | NA | N | Y | Y | N | Fair |
Ulualp et al. [31] | Y | Y | Y | Y | N | N | N | Y | Y | N | N | NR | NA | N | Fair |
Umay et al. [32] | Y | Y | NR | Y | Y | N | N | Y | Y | Y | N | Y | Y | N | Fair |
Vetter-Laracy et al. [19] | Y | Y | Y | Y | N | N | N | Y | Y | NA | N | NR | Y | N | Fair |
Willette et al. [20] | Y | N | Y | Y | N | N | N | NA | NA | NA | N | N | NA | N | Fair |
Data Synthesis
Results
Search Results
Risk of Bias and Quality Assessment
Study Population
Study | N | Gender Samplea | Age in monthsb (range; Mdn/M ± SD)c | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
(% f) Years: | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 + | |||
Armstrong et al. [12] | 5 | 40 | Premature born, NICU (100%) | 8.7–9.6 (PMA); M = 9.1 ± 0.3 | ||||||||||
Averin et al. [13] Beer et al. [27] | 63 | NR | Hypoplastic heart syndrome, after Norwood operation | Mdn = 0.2 | ||||||||||
da Silva et al. [21] | 30 | 47 | Traumatic brain injury (4), cerebral palsy (6), encephalopathy (5), encephalitis (3), genetic syndrome (4), multiple congenital anomalies (3), complex cerebellar malformation (1), leukodystrophy (1), epilepsy (2), progressive dystonia (1) | 10–216; Mdn = 60 | ||||||||||
Hartnick et al. [28] | 30 | 40 | Cerebral palsy (11), genetic malformations (4), gastroesophageal reflux (4), respiratory diseases (18), other (6) | 10.5–37.3; M = 25.8 ± 21.2 | ||||||||||
Kamity et al. [14] | 568 | NR | Structural (35%), neurologic (33%), pulmonary (6%), genetic (7%), gastrointestinal (10%), cardiovascular (3%), metabolic (1%), prematurity (4%), psychiatric (1%) | 2–204; Mdn = 30 | ||||||||||
Leal et al. [22] | 5 | 20 | Premature born, bronchopulmonary dysplasia, NICU (100%) | 8.4–9.6 (CGA); M = 8.97 ± 0.4 | ||||||||||
Leder et al. [23] | 9 | 56 | Congenital zika syndrome (100%) | 9.5–16.8; M = 9.8 | ||||||||||
Leder & Karas [10] | 5 | 40 | Mechanically ventilated via tracheotomy: Bronchopulmonary dysplasia (3), subglottic stenosis (1), acute transverse myelitis (1), patent ductus arteriosus (2), tracheomalacia (1) | 3–14; M = 10.2 | ||||||||||
Link et al. [11] | 30 | 37 | Motor vehicle crash (8), neurological disorders (7), gunshot wound or stabbing (3), laryngotracheal abnormalities (3), acetaminophen overdose (1), bronchopulmonary dysplasia (1), genetic syndrome (3), patent ductus arteriosus (1), gastroenterologic (2), poor feeding (1) | 0.36–240; M = 124.8 | ||||||||||
Marques et al. [15] | 100 | 30 | Neurologic disorder (e.g., hypotonia, cerebral palsy, stroke, asphyxia) (33), gastroesophageal reflux (25), history of rec. pneumonia (26) | 1–288; Mdn = 32.7 | ||||||||||
Mills et al. [16] | 11 | NR | Isolated Pierre-Robin sequence (100%) | M = 1.1 ± 0.6 | ||||||||||
Pavithran et al. [24] | 23 | 52 | Laryngomalacia: without comorbidity (12), neurologic diagnosis and/or low muscle tone (5), Down Syndrome (2), primary congenital cardiac anomalies (4), premature born (4), repaired tracheoesophageal fistula (2) | 0.23–8.5 | ||||||||||
Richter et al. [25] | 65 | 43 | Neurological disorders (80%), congenital cardiac disease (31%), genetic syndrome (26%), gastroesophageal reflux disease (23%), prematurity (23%), upper aerodigestive tract anomalies (20%), seizure disorder (57%) | 0.4–36; M = 9.9 ± 9.8 | ||||||||||
Sitton et al. [29] | 50 | NR | Laryngomalacia/supraglottoplasty: Isolated (5), gastroesophageal reflux disease (48), neurologic disease (11), cardiac disease (18), genetic disorder (17) | 0.3–26.8; Mdn = 4.5 | ||||||||||
Suiter et al. [30] | 79 | 44% | Neurologic disorder (25), genetic disorder (28), congenital heart defect (22), prematurity (15), vocal fold dysfunction (17), micrognathia (3), tonsillar hypertrophy (11) | 0.4–170; M = 30 ± 26.4 | ||||||||||
Suskind et al. [17] | 56 | 41 | Surgery (13), general medical (8), pulmonary (2), cancer (2), stroke (3), TBI (10), progressive neurological (7), cervical spinal cord injury (3), acute encephalopathy (3), seizure disorder (1), other neurological (4) | 24–216; M = 160.8 ± 56.4 | ||||||||||
Suterwala et al. [18] | 17 | 25* | Gastroesophageal reflux disease | 1–9.7; M = 5.4 ± 3.7 | ||||||||||
Ulualp et al. [31] | 25 | 60 | Respiratory distress syndrome, NICU | 8.5–11.3; M = 9.2 ± 0.7 | ||||||||||
Umay et al. [32] | 40 | 30 | Gastroesophageal reflux (17), asthma (8), seizure disorder (15), cerebral palsy (5), Down syndrome (1), velocardiofacial syndrome (3), neonatal hypotonia (2), excision of posterior fossa ependymoma (1), spinal muscular atrophy (1), trisomy 9 (1), no comorbidity (3) | 3–204 | ||||||||||
Vetter-Laracy et al. [19] | 251 | 31,5 | Cerebral palsy (100%) | 48–96; M = 68.4 ± 20.4 | ||||||||||
Willette et al. [20] | 62 | 34 | Premature born | 8.7–10.1 (PMA); Mdn = 9.1 | ||||||||||
Armstrong et al. [12] | 23 | 39 | Neurologic (10), structural (6), cardiorespiratory (3), normal (4) | 0.4–10; M = 3.2 |
Implementation Protocols
Equipment
FEES Procedural Steps
Study | FEES performed by; assistance | Positioning of the child/adolescent | FEES procedural steps |
---|---|---|---|
Armstrong et al. [12] | SLP; OT, lactation consultant nurse, otolaryngologist, neonatologist | With endoscope in place: mother’s preferred position | 2. Direct assessment of swallowing (not reported in detail) |
Averin et al. [13] | NR; NR | NR | 1. Observation of anatomical structures and a) secretion management 2. Direct assessment of swallowing 3. Compensatory strategies |
Beer et al. [27] | Pediatric neurologist; two SLPs, nurse | Individually: buggy, wheelchair, nurse’s lap, bed | 1. Observation of anatomical structures and a) secretion management 2. Direct assessment of swallowing |
da Silva et al. [21] | Otolaryngologist; SLP | Sitting | 2. Direct assessment of swallowing (not reported in detail) |
Hartnick et al. [28] | Otolaryngologist; SLP, nurse | On caretaker´s lap or accompanied; stabilized while telescope is introduced | 1. Observation of anatomical structures and a) secretion management and b) sensory testing (air pulse) 2. Direct assessment of swallowing 3. Compensatory strategies |
Kamity et al. [14] | Pediatric otolaryngologist; neonatologist, SLP, nurse | Tightly swaddled, semi-reclined position at 45–90° angle, feeder stabilizes head | 1. Observation of anatomical structures 2. Direct assessment of swallowing 3. Compensatory strategies (if necessary) |
Leal et al. [22] | Otolaryngologist; SLP | NR | Reference to standard FEES protocol (Langmore [4]): 1. Observation of anatomical structures 2. Direct assessment of swallowing 3. Compensatory strategies (if necessary) |
Leder et al. [23] | Otolaryngologist; NR | NR | Reference to standard FEES protocol (Langmore [4]) with slight modification: 1. Observation of anatomical structures 2. Direct assessment of swallowing (evaluation of the first 6–20 boluses) |
Leder & Karas [10] | Otolaryngologist; NR | Upright | Reference to standard FEES protocol (Langmore [4]), no further specification |
Link et al. [11] | Pediatric otolaryngologist; SLP | Upright, sitting on the lap, head stabilized | 1. Observation of anatomical structures and a) secretion management 2. Direct assessment of swallowing 3. Sensory testing (air pulse) |
Marques et al. [15] | NR; NR | On mother’s lap | 2. Direct assessment of swallowing (not reported in detail) |
Mills et al. [16] | Pediatric otolaryngologist; SLP, nurse, lactation consultant | On mother’s lap, latching after insertion of endoscope | 1. Observation of anatomical structures and a) secretion management [Securing endoscope with rubber band and latch] 2. Direct assessment of swallowing 3. Compensatory strategies (re-positioning) |
Pavithran et al. [24] | Otolaryngologist; SLP | 45–90° reclining position on caretaker’s arm | 1. Observation of anatomical structures and a) secretion management and b) sensory testing (touch method) 2. Direct assessment of swallowing (in case of aspiration, repetition of the consistency) |
Richter et al. [25] | NR; NR | Upright or semi-reclined at caregiver’s lap with gentle restraint | b) Sensory testing (in 28 children, air pulse) 2. Direct assessment of swallowing |
Sitton et al. [29] | Otolaryngologist; SLP, nurse | NR, stabilization of head by caregiver or nurse | 1. Observation of anatomical structures and a) Secretion management 2. Direct assessment of swallowing |
Suiter et al. [30] | Otolaryngologist; NR | NR | Reference to standard FEES protocol (Langmore [4]) with slight modifications: 1. Observation of anatomical structures 2. Direct assessment of swallowing |
Suskind et al. [17] | NR; NR | Upright or semi-reclined at caregiver’s lap with gentle restraint | b) Sensory testing (air pulse) 2. Direct assessment of swallowing |
Suterwala et al. [18] | SLP; OT | Swaddled, placed in the feeder’s arms in an elevated side-lying position at 20–30° elevation | 1. Observation of anatomical structures and a) Secretion management 2. Direct assessment of swallowing |
Ulualp et al. [31] | NR; NR | On the caregiver’s lap, upright | b) Sensory testing (air pulse) 2. Direct assessment of swallowing |
Umay et al. [32] | Otolaryngologist; NR | Highest possible upright sitting position | 2. Direct assessment of swallowing (not reported in detail) |
Vetter-Laracy et al. [19] | Pediatrician; nurse | On the caregiver’s lap, stabilized head during the procedure | 1. Observation of anatomical structures and a) Secretion management 2. Direct assessment of swallowing 3. Compensatory strategies |
Willette et al. [20] | Otolaryngologist; two SLPs, nurse | Nurse stabilizes head while insertion; breastfeeding in position typically used | 1. Observation of anatomical structures and a) Secretion management 2. Direct assessment of swallowing 3. Compensatory strategies (in case of unsafe breastfeeding) |
Study | Type (designation), manufacturer, diameter (mm) | Topical anesthesia and decongestion, application | Calming techniques | Volume and consistencies | Thickener | Food dye and dosage |
---|---|---|---|---|---|---|
Armstrong et al. [12] | Fiberoptic (ENF-XP), Olympus, 2.2 | None | 0.2 ml sucrose solution (pacifier), calming strategies | Breastfeeding | NA | Green food dye McCormick (Sparks, Maryland), 0.05 ml in 15 ml expressed human milk via syringe prior to latch |
Averin et al. [13] | NR, NR, 2.2 | Lidocaine gel (2%), on endoscope | NR | Breast milk or formula (small tastes) | NR | NR |
Beer et al. [27] | Video bronchoscope (BF-3C160), Olympus, 3.8 | Decongestive nasal drops, no topical anesthesia | NR | a. Fruit puree b. Liquid c. Bread (different consistencies dependent on aspiration risk) | NR | Colored in blue |
da Silva et al. [21] | Fiberoptic, Machida Endoscope, 3.2 | NR | NR | a. Liquid (apple juice) b. Puree (1/2 measuring spoon thickener, apple juice powder, and 100 ml water) | Modified instant corn starch (Nutilis, Support, Sao Paulo, Brazil) | Liquid yolk-colored food dye liquid indigo blue (Mix, Sao Paulo, Brazil) |
Hartnick et al. [28] | Fiberoptic, NR, NR | 1:1 tetracaine/oxymetazoline hydrochloride | NR | Developmentally appropriate | NR | Food coloring |
Kamity et al. [14] | Fiberoptic, Pentax, 2.4 | None | Sucrose solution (24%, pacifier) | Thin barium (50% dilution), 30 ml (similac volu feeder) | NR | Green Food Color McCormick (Sparks, MD, USA), two drops |
Leal et al. [22] | Fiberoptic, Machida Endoscope, 3.2 | NR | NR | a. Liquid b. Thickened liquid (50 ml/3 g) 1 ml, 3 ml, 5 ml via syringe c. Foodpaste or puree (2 spoons) | Modified corn starch (Sustap, Prolev, Brazil) | Liquid indigo blue food dye |
Leder et al. [23] | Fiberoptic (ENF-P3), Olympus, 3.6 | None | NR | Liquid (milk/formula) via bottle | NR | None (white milk) |
Leder & Karas [10] | Fiberoptic (ENF-XP or ENF-P3), Olympus, 2.2 or 3.6 | None | NR | Bottle-fed: clear or nectar-thickened liquid; others: a. Puree (custard, 5 ml) b. Liquid (milk, 5 ml) c. Solid (i.e., cracker, if indicated) | Yes/NR | Blue dye |
Link et al. [11] | Fiberoptic (FNL 10 AP), Pentax, 3.2 | Topical nasal anesthetic | NR | a. Liquids b. Variety of developmentally appropriate textures | NR | Green food color |
Marques et al. [15] | Fiberoptic (ENF-P4), Olympus, 3.2 | None | NR | Liquid or thickened liquid (milk) through bottle | Modified corn-based flour | Aniline color (blue) |
Mills et al. [16] | Fiberoptic, Telepack Storz, 1.9 | Lidocaine gel (2%), on endoscope | NR | Breastfeeding | NA | NR |
Pavithran et al. [24] | Videoscope (11,101 VPS), Telepack Storz, 3.7 | Xylometazoline, Lidocaine gel (2%), on endoscope | NR | Developmentally appropriate a. Thin b. Thick c. Puree | Rice cereal | Apple green dye |
Richter et al. [25] | Fiberoptic, or fiberoptic and air pulse channel (FNL 10 AP), KayPENTAX, 2.5 or 4.0 | Lidocaine gel (2%), outer surface of endoscope | NR | Formula Bottle-fed | NR | NR |
Sitton et al. [29] | NR, NR, NR | None | NR | Developmentally appropriate | NR | Standard household green food coloring, one drop per 4–8 oz |
Suiter et al. [30] | Fiberoptic (ENF-P3), Olympus, 3.6 | None | NR | a. Puree (pudding, 3 × 5 ml) b. Liquid (milk, 3 × 5 ml) | NR | None (yellow puree and white milk) |
Suskind et al. [17] | Fiberoptic (FNL 10 AP), Pentax, 4.0 | Lidocaine gel (4%), outer surface of endoscope | NR | a. Liquids b. Variety of developmentally appropriate textures | NR | NR |
Suterwala et al. [18] | Fiberoptic (ENF-XP), Olympus, 2.2 | None | 2 ml Sucrose solution (24%), NNS, sound and light reduction | a. Thin consistency (breastmilk or formula via slow-flow nipple) b. Subsequent consistencies and nipple types based on response to initial bottle | Rice cereal (Beech-Nut, USA (breastmilk not thickened) | Green food dye McCormick (Sparks, MD, USA)/, two drops 0.1 ml/30 ml bottle |
Ulualp et al. [31] | Fiberoptic and air pulse channel (ENT-1000), Vision Sciences, 2.4 | Lidocaine gel (2%), cotton-tipped applicator | NR | a. Liquids b. Variety of developmentally appropriate textures | NR | NR |
Umay et al. [32] | Fiberoptic, Storz, 3.4 | NR | NR | a. Liquid (water) b. Semi-solid (thickened water) c. Solid (bread) | Yes/NR | NR |
Vetter-Laracy et al. [19] | Fiberbronchoscope (BF-XP 190), Olympus, 3.1 | Lidocaine (2.5%) and prilocaine (2.5%) gel (Emla creme) | NR | a. Liquid (formula bottle-fed) b. Thickened formula (in case of aspiration) | Modified corn starch (Resource Thickenup), 6.4 g/100 ml | Dye, one drop |
Willette et al. [20] | NR, NR, 2.7 | Lidocaine gel (4%), distal end of endoscope | Breastfeeding | Breastfeeding | NA | Standard green food coloring via toothette (oral care stick) |
Study, country | Design | FEES-based outcome (result/sample size) (in case of repeated testing, first measurement) | Complications |
---|---|---|---|
Armstrong et al.[12] USA | Prospective, cross-sectional, pilot | Penetration of milk (1/2), secretion (1/2); aspiration of milk (0/2), secretion (1/2) | None |
Averin et al. [13] USA | Retrospective, cross-sectional | Swallowing dysfunction (10/63) | None |
Beer et al. [27] Germany | Retrospective, cross-sectional | Penetration: Saliva (5/30), puree (7/24), thin liquid (5/21) Aspiration: Saliva (10/30), puree (7/24), thin liquid (7/21) Silent aspiration: Saliva (9/30), puree (3/24), thin liquid (1/21) | Short dips of oxygenation (< 85%, n = 2), spontaneous recovery |
da Silva et al. [21] Brazil | Prospective, cross-sectional | (Observer 1 and observer 2/N) Early spillover: Puree (5 and 8/30), liquid (9 and 14/30) Pharyngeal residue: Puree (13 and 9/30), liquid (10 and 9/30) Penetration: Puree (4 and 4/30), liquid (15 and 13/30) Aspiration: Puree (0 and 0/30), liquid (6 and 4/30) | NR |
Hartnick et al. [28] USA | Retrospective, cross-sectional | Diagnostic categories according to Burklow et al. (1998) baseline feeding recommendations | NR |
Kamity et al. [14] USA | Prospective, cross-sectional, pilot | Penetration (5/5), aspiration (3/5) | None |
Leal et al. [22] Brazil | Retrospective, case series | Premature spillage (9/9), delay swallowing reflex (8/9), hypopharyngeal residue (4/9), PAS 1 (1/9), PAS 5 (3/9), PAS 7 (4/9), PAS 8 (1/9) | None |
Leder et al. [23] USA | Prospective, cross-sectional | Aspiration or unsafe swallow (1/5) | NR |
Leder & Karas [10] USA | Prospective, cross-sectional | Not systematically reported; no findings (13/23), aspiration (5/10; silent: 3), aspiration (3/7) | NR |
Link et al. [11] USA | Retrospective, cross-sectional | Hypopharyngeal secretion: None (48/100), minimal (21/100), moderate (9/100), severe (22/100), penetration (46/96) aspiration (31/96) LAR absent (22/100) | NR |
Marques et al. [15] Brazil | Prospective, observational | Aspiration risk (7/11) defined as milk reflux, delayed initiation of swallowing or residue | NR |
Mills et al. [16] New Zealand | Retrospective, cross-sectional | Aspiration and/or penetration (15/23), silent aspiration (10/23) | None |
Pavithran et al. [24] India | Prospective, cross-sectional | Glottic secretion (17/65), excessive pharyngeal secretion (23/65), premature spillage (44/65), pharyngeal residue (33/65), penetration (42/65), aspiration (15/65), weak/absent LAR (16/65) | NR |
Richter et al. [25] USA | Retrospective | Penetration (44/50), aspiration (36/50), LPST (mm Hg in 28 patients: M = 8.23 ± 1.85) | NR |
Sitton et al. [29] USA | Retrospective, cross-sectional | Report on feeding recommendations, spillage, penetration, aspiration, and residue included in logistic regression | NR |
Suiter et al. [30] USA | Prospective, cross-sectional | Aspiration included in test statistics for reference test | NR |
Suskind et al. [17] USA | Retrospective, cross-sectional | Hypopharyngeal pooling (15/17), LPST (mm Hg M = 6.3 ± 1.0, penetration (5/17), aspiration (7/17) | NR |
Suterwala et al. [18] USA | Prospective, cross-sectional | Penetration and aspiration included in intra- and interrater-reliability | None |
Ulualp et al. [31] USA | Retrospective, cross-sectional | Laryngopharyngeal sensation: Normal (6/40), moderate (20/40), severe (10/40), no response (4/40) pharyngeal pooling (24/40), premature spillage (17/40), residue (6/40), penetration (14/40), aspiration (10/40) | NR |
Umay et al. [32] Turkey | Prospective, cross-sectional | Dysphagia level according to Warnecke et al. [43], self-developed classification: 1 = normal (29/251), 2–3 = mild (72/251), 4–5 = moderate (79/251), 6 = severe (71/251) | NR |
Vetter-Laracy et al. [19] Spain | Retrospective, cross-sectional | Pharyngeal pooling (14/62), penetration/aspiration (44/62), signs of GERD (17/62), residue (24/62) | None |
Willette et al. [20] USA | Retrospective, cross-sectional, case series | Functional swallowing (2/24), penetration (20/24), aspiration (12/24) | None |