There is a dearth of validated neonatal feeding assessment instruments available for use in clinical practice in resource-constrained developing contexts. The Neonatal Feeding Assessment Scale (NFAS) was developed to identify and diagnose oropharyngeal dysphagia (OPD) in neonates. The main aim of the study was to develop and test the psychometric performance of a clinical assessment scale for the early identification and diagnosis of OPD in the high-risk neonatal population in South Africa. To meet the main aim, the research project was divided into three separate studies. The research design across the three studies was an exploratory sequential mixedmethod design. The NFAS was developed using the Delphi method in the first study. Two international and three South African speech-language therapists (SLTs) formed the expert panel that participated in two rounds of electronic questioning to develop the instrument. For the second and third studies, a comparative crosssectional within-subject design was used. In the second study the participants were 20 neonates with a median age of 35.0 weeks gestational age (GA) in a 29-bed neonatal intensive care unit (NICU). In the third study 48 participants with a median age of 35.5 weeks GA were included. During the second study the preliminary psychometric performance of the NFAS was determined and in the third study, the final psychometric properties of the NFAS were determined to describe the validity and reliability of the NFAS. The NFAS was developed and approved, using expert collaboration through the Delphi method in the first study. All participants agreed on the need for the development of a valid clinical feeding assessment instrument to use with the highrisk neonatal population. The initial NFAS consisted of 240 items across 8 sections; after the Delphi process was implemented, the final format was reduced to 211 items across 6 sections. The final format of the NFAS is scored using a binary scoring system guiding the clinician to identify the presence or absence of OPD. All members agreed on the format, the scoring system and the feeding constructs addressed in the final format of the NFAS. The second study showed that 9 out of 20 participants presented with OPD on the NFAS. Comparison of NFAS results with modified barium swallow studies (MBSS). indicated that all participants with OPD were correctly identified (100% specificity). The sensitivity was 78.6%, indicating that three participants were falsely identified with OPD on the NFAS. The instrument took approximately 30 minutes to complete during observation of a habitual feeding session with the mother. Inter-rater reliability was determined on 50% (n=10) of the study sample. Substantial agreement (80%) was obtained between two raters in five of the six sections of the NFAS and on the diagnostic outcome of the scale. The preliminary performance of the NFAS appeared to be promising. The formal validation process of the NFAS then followed on a larger sample in the third study. Results of the third study indicated that 15 of the 48 participants were identified with OPD on the NFAS, whereas 14 of these 15 infants were diagnosed on MBSS. A sensitivity score of 78.6% was obtained, with specificity determined to be 88.2% for the newly developed NFAS. The subsequent accuracy of the NFAS to identify OPD correctly was 85.4% when compared with the MBSS outcome. Inter-rater reliability was determined using 35% of the sample. The agreement on overall instrument outcome between the two raters was considered substantial beyond chance, with Cohen's Kappa at 0.598, with an asymptotic standard error of 0.211. The scale may be of use to SLTs working without MBSS equipment and to reach underserved preterm neonates. Inexperienced SLTs may benefit from observational prompts provided by the NFAS. The NFAS may be suitable for use in South Africa and similar developing contexts to identify and diagnose high-risk neonates with OPD. / Thesis (DPhil)--University of Pretoria, 2016. / Speech-Language Pathology and Audiology / DPhil / Unrestricted

PURPOSE: Sufficient hyoid excursion plays a critical role in facilitating multiple facets of functional pharyngeal motion, phonation, and nutritional intake; however, objective quantification of hyoid displacement during modified barium swallow studies relies on variable practice protocols. This study sought to compare hyoid displacement methodological differences in the dysphagia literature to establish new clinically feasible references of normative values and measurement strategies. METHOD: The current study incorporated re-analysis of Molfenter and Steele (2011)’s meta- analysis according to measurement strategies (anterior and superior versus hypotenuse (total) displacement as well as rest-to-peak versus frame-by-frame quantification), bolus volume, and participant characteristics (sex and age). Conversion of data was completed using the Pythagorean theorem, and resulting data was then compared within the study itself and externally to Leonard et al. (2000). Two Tailed Independent t-tests and a linear regression were completed to assess the relationship between analysis factors and hyoid displacement. RESULTS: Males were found to have significantly higher hypotenuse hyoid displacement than females. No statistical significance was found between the predetermined age groups (“old” and “young”) or newly determined age groups (“old,” “young,” and “middle age”). A linear relationship between increasing bolus volume and hypotenuse hyoid displacement was established. Rest-to-peak and frame-by-frame internal measurement strategies were statistically identical, but the rest-to-peak strategy incorporates qualitative improvements regarding efficiency. The re-analysis of anterior and superior hyoid displacement norms within Molfenter and Steele (2011) resulted in slightly lower hypotenuse normative values when compared to Leonard et al (2000). CONCLUSION: The current findings suggest that measurement of hyoid hypotenuse displacement is a more efficient measurement strategy and is effective in incorporating the hyoid’s anterior and superior displacement. For clinicians, these findings suggest that normal hyoid excursion may not need to be as large as Leonard et al.’s (2000) norms proposed to be classified as within normal limits for healthy individuals. New references on normative values suggest that as bolus volumes increase, so too does the hyoid displacement, with an expected plateau due to anatomical constraints, to facilitate safe swallows. Furthermore, although rest-to-peak and frame-by-frame internal measurement strategies were statistically identical in quantifying hyoid displacement, the rest-to-peak measurement strategy stood superior when considering the qualitative improvement in a clinician’s time management. Moreover, analysis of participant characteristics identified that hyoid excursion is larger for males than females and that presbyphagia likely results in slightly reduced displacement. Further investigation is warranted and required to better understand hyoid excursion variability and refine best practices.