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Teachers’ self-efficacy beliefs in teaching learners with learning barriers in one mainstream secondary school in Soweto
(University of the Witwatersrand, Johannesburg, 2024-10) Twala, Busisiwe Prudence; Ajayi, Oluwakemi; Aloka, Peter
Examining teachers' self-efficacy is crucial in the field of inclusive education. This concept plays a vital role as it directly influences how educators address the unique requirements of learners facing learning challenges. Despite its importance, there are significant gaps in research within the South African context regarding the obstacles teachers encounter when implementing inclusive education, particularly in relation to self-efficacy. The absence of thorough research could be a factor of the ongoing, valid worries in township high schools. Several research conducted globally demonstrate how self-efficacy attitudes regarding inclusive education influence teaching methods and could be advantageous to learners. The primary goal of this study was to find out about teachers’ self-efficacy beliefs in accommodating learners with learning difficulties in a mainstream township high school in Soweto. This research employed a qualitative method that worked with the interpretive research paradigm. The study's design was a case study. Using the purposive sampling method, the sample size of eight teachers from grades 8–12 at the chosen school was determined. For the eight participants, a semi-structured individual interview was used as the study tool. Thematic framework analysis was utilized to facilitate the examination of internal data. Additionally, the reliability of the qualitative data was guaranteed. The research findings revealed varying levels of self-efficacy among teachers in accommodating diverse learners in their classrooms. Educators with high self-efficacy demonstrated superior organizational skills and were more happily effective in teaching learners with learning disabilities despite the contextual challenges. Conversely, those with low self-efficacy perceived inclusive education as challenging due to the psychological and social hurdles faced by both teacher and learners in the school environment. Additionally, the study identified several strategies employed by teachers to support learners with disabilities, including differentiated instruction, scaffolding, and responsive teaching techniques. The study utilized certain strategies with the goal of incorporating students with learning challenges into regular classrooms. The research suggests that educators need to tackle serious hurdles affecting their own efficacy in teaching effectiveness. It further proposes that continuous professional development programs should be organized by the Education Department, focusing on better understanding and implementation of SIAS policy (Screening, Identification, Assessment, Support Provisioning and Monitoring).
The Impact of using Monolingual pedagogies in South African Classrooms on the Academic Performance and Social Inclusion of African Learners who are Learning through an Additional Language
(University of the Witwatersrand, Johannesburg, 2024) Shumba, Thato Jessica; Charamba, Erasmos
Within the South African educational landscape, a critical challenge arises when transitioning to an additional language as the sole medium of instruction. This hasty embrace often neglects the crucial development of both Basic Interpersonal Communication Skills (BICS) and Cognitive Academic Language Proficiency (CALP) in the learners' first languages, also known as their mother tongue. This oversight is particularly concerning when implemented as early as grade four, as the pressure of globalization often dictates a swift shift from mother tongues to English as the primary language of instruction. This abrupt linguistic transition exacerbates existing educational disparities, highlighting the urgent need for a critical examination of language policies and their practical implementation within South African schools. This study employed a mixed-methods approach to investigate whether monolingual pedagogies contribute to the academic performance of Grade 4 learners studying in an additional language (English) different from their mother tongues. The research took place in a township school in Kaalfontein, predominantly populated by Black African learners with no prior exposure to English outside the classroom setting. The mixed-method design involved two key data sources: a sample of approximately 140 learners divided into control and experimental groups, and a range of data collection tools. Both groups participated in pre- and post-test assessments to gauge their academic progress in English, while the experimental group received additional interventions employing translanguaging and multilingual pedagogy approaches. These approaches deliberately intertwined learners' home languages with English in the learning process. Data from classroom observations and semi-structured interviews with participants further enriched the study. Quantitative data from the written tests was analysed using R-computing software, while interview responses were analysed through Glaser and Laudel's model of grounded theory. The paired t-test revealed statistically significant differences in post-test performance between the groups, favouring the experimental group. This suggests that the translanguaging and multilingual interventions positively impacted learners' academic performance in English, providing them with a valuable bridge between their home languages and the language of instruction. This study's findings offer compelling evidence that monolingual pedagogies may not be the optimal approach for learners acquiring an additional language. By incorporating translanguaging and multilingual strategies, educators can leverage learners' existing linguistic resources, fostering deeper understanding and ultimately improving academic outcomes in diverse educational settings.
Effects of aqueous extract of kolanut (Cola nitida) on Sprague Dawley dams and exposure on the hippocampus of the progeny
(University of the Witwatersrand, Johannesburg, 2024) Atiba, Foluso Ayobami; Ihunwo, A. O.
Background: Kolanut, a tropical nut eaten by people across sub-Sahara Africa, contains caffeine, theobromine, catechins, and tannins. Pregnant women often eat it to suppress morning sickness. This study investigated the effects of kolanut on the structure and functions of the developing hippocampus. Methods: Kolanut extract at 400 mg/kg of body weight infused in gel cubes was fed to 6 female and gel cubes without kolanut to control 6 female Sprague Dawley rats from the first day of mating till parturition. Several behavioral tests were administered on the pups namely surface righting (SR), cliff avoidance (CA) across different age group, post-natal day (PND) 4, 5, 6 & 7, head rising, head pivoting, locomotion, open field, novel object recognition (NOR) and location (NOL), and radial-arm maze (RAM) PND 21 and 56. Their hippocampi were subjected to histology [Nissl, Golgi-cox], immunohistochemistry (Ki67 and DCX), biochemistry [malondialdehyde (MDA), superoxide dismutase (SOD), reduced glutathione (GSH), glutathione peroxidase (GPX), transcription factors [brain-derived neurotrophic factor (BDNF), and acetylcholine (ACh)]. Expression of immediate (c-fos & c-jun) and memory genes (dlg3, dlg4, creb1 & creb2) were also determined. Results: Difficulty to get pregnant was observed in 33.3% of the dams; 16.7% had a still birth while 4.0% of the pups from dams fed kolanut-treated diet had paralysis of the limb. Kolanut significantly reduced the body weight (p < 0.001 – p < 0.0001) and increased brain weight, especially at PNDs 56 & 70 (p < 0.001 – p < 0.0001) of the dams and pups compared to the control. Food consumption was significantly (p < 0.05) lower for dams on kolanut-treated diet, but their water intake was significantly higher (p < 0.001). Kolanut significantly affected the behavioral indices of the animals; it significantly increased the latency of CA and SR tests across age groups (p <0.0001 and p < 0.0001 respectively). The frequency of head rising, frequency of pivoting and its latency, and locomotion were significantly (p < 0.01 – p < 0.0001) lower in animals fed kolanut-treated diet. Animals fed kolanut-treated diet showed anxiety during the open field tests on PNDs 21 and 56, and exhibited increased line crossing, corner time, distance covered and velocity (p < 0.05 – p < 0.0001). Frequencies of freezing episodes, grooming, rearing, fecal bolus and urination were also significantly (p < 0.01 – p < 0.0001) higher in animals that received kolanut-treated diet. The discrimination ratio of NOR and NOL were significantly 5 lower in animals fed kolanut-treated diet; they took longer duration to complete the tasks in RAM. Results from Golgi staining showed that kolanut caused pyknosis (p < 0.0001), inflamed soma, reduced aborization and synapses (p < 0.0001), reduction in spine quantity (p < 0.0001), change in morphology, fragmentation and constriction of the dendrites of the hippocampal neurons. When stained with DCX, the hippocampi of animals fed kolanut showed decrease in mean density of neuronal cells (p < 0.0001), increase number of pyknosis (p < 0.0001) and chromatolytic cells (p < 0.0001), neuronal atrophy, clumping, multi-layering and gliosis of the DG cells. In addition, the Ki67 showed a significant loss of proliferating cells (p < 0.0001) in the sub-granular zone of the DG. Kolanut significantly (p= 0.0067) increased the MDA and glutathione peroxidase levels. BDNF and ACh were significantly (p = 0.0001) increased by kolanut. A significant and positive correlation was found between SRT and MDA in PND 7 (r = 0.99, p = 0.0059), grooming and MDA in PND 56 (r = 0.77, p = 0.0252), grooming and BDNF in PND 21 (r = 0.76, p = 0.0297). A significant negative correlation was obtained between rearing and ACh in PND 56 (r = -0.83, p = 0.0115), Ki67 and MDA (p = 0.0213), and DCX cells and BDNF (p = 0.017). Prenatal kolanut consumption caused downregulations of cfos mRNA and cjun mRNA and creb1levels, an increase in creb2 level and a significant reduction in the levels of dlg3 mRNA and dlg4 mRNA, thus affecting the dendrites and spine morphology. Conclusion: Prenatal kolanut consumption adversely affected food intake, behavior, neuronal morphology, decreased neurogenesis and neuroplasticity and resulted in downregulation of genes important for normal development of the neurons and synapses. It exerted anti-neuroprotective effects by inducing oxidative stress, altering cholinergic system activity, stimulating over- expression of BDNF protein and concomitantly causing changes in morphology of the hippocampal neurons. Pregnant women and those of reproductive status need to be made aware of the adverse effects of kolanut consumption during pregnancy.
A nexus of student food (in)security, common mental disorders, and academic success in the midst of the covid-19 pandemic
(University of the Witwatersrand, Johannesburg, 2024) Wagner, Fezile
Background: South African Higher Education Institutions (HEIs), akin to their global counterparts, grapple with the challenge of low throughput and dropout rates, as students often extend beyond the minimum required duration to complete their academic programmes. Research has identified the first year of study as the period carrying the highest risk for student failure and attrition. Factors such as prior academic performance, family background, and the student's ability to integrate into various aspects of university life emerge as significant determinants of academic success. Notably absent from these determinants are considerations pertaining to student wellbeing, encompassing mental health and food security status. These aspects assumed heightened awareness during the coronavirus disease of 2019 (COVID-19) pandemic, which posed threats to social, economic physical, and psychological wellbeing. For university students, the pandemic necessitated a swift adoption of a new pedagogical approach - Emergency Remote Teaching and Learning (ERTL) – along with most students being forced to relocate home, while simultaneously facing the harsh realities of mass job loss, illness, and grief brought on by the pandemic. Objective: This PhD aims to measure the impact of the COVID-19 pandemic on first time, first year university students’ food insecurity and mental health status (specifically, the common mental disorders (CMDs): anxiety, depression and mental distress symptoms), as well as to understand the implications of this on academic success. Methods: Taking place at a large, urban South African university, this research made use of a concurrent triangulation research design. Two cross-sectional surveys were administered in the years 2019 (before the pandemic) and 2020 (during the COVID-19 pandemic). Included in the surveys were validated tools used to measure depression (Patient Health Questionnaire 9-item (PHQ 9)), anxiety (Generalized Anxiety Disorder 7-item (GAD-7)), and mental distress symptoms. The Household Food Insecurity Access Scale (HFIAS) was also included in the two cross-sectional surveys to measure food insecurity levels. This tool was validated before being administered. Academic success was evaluated through two distinct approaches: i) the first method involved scrutinizing student failure rates and progress; ii) the second method focused on assessing retention and dropout rates. Qualitative data collection took place in 2020 and took the form of in-depth interviews (IDIs) and focus group discussions (FGDs). ii Results: Due to the lockdown directive, students living at home during studies increased from 29% in 2019 to 88% in 2020. In terms of the student failure rate, a reduction was noted from 23.4% (95% CI: 20.7- 26.3) in 2019 to 14.6% (95% CI: 12.0- 17.7) in 2020. Teaching staff acknowledged that students seemed to have a better grasp of complex content during ERTL, and feedback from students themselves indicated the benefits of being able to access and replay lecture recordings as well as the flexibility introduced by ERTL. Increased dropout levels were found - increasing from 5.5% (95% CI 4.2- 7.2) in 2020 to 10.5% (95% CI 8.2- 13.2) in 2021. Moderate food insecurity status (OR= 2.50; 95% CI: 1.12- 5.55; p=0.025), and severe mental distress symptoms (OR= 7.08; 95% CI: 2.67- 18.81; p<0.001) increased the odds of student dropout. The adjusted prevalence of food security was found to be better during the later time point - 30.3% (95% CI: 27.4- 33.4) in 2019 before the COVID-19 pandemic, to 37.9% (95% CI: 34.1- 41.9) 2020 during the COVID-19 pandemic. While the prevalence of CMD symptoms worsened over time; the prevalence of severe anxiety symptoms increased from 17.5% (95% CI: 15.2- 20.1) in 2019 to 25.4% (95% CI: 22.0- 29.1) in 2020. Conclusions: The study found an increase in student dropout and a decrease in failure rates during the pandemic, findings corroborated by other studies. Analyses suggest mental distress symptoms and food insecurity were important drivers of student dropout during the pandemic. Findings highlighted a clear decline of food insecurity when compared to figures before the pandemic. Literature highlighted how food and eating practices change when students are at home; this may have reduced food insecurity levels. A significant increase in the prevalence of CMD symptoms during the COVID-19 pandemic was observed and is believed to have been influenced by various intricate factors including grief, job loss and confinement. These findings provide important insights to HEIs in the event of future disruptions and as they embrace hybrid teaching and learning approaches post COVID-19. Although the reduction in failure rates may have been possibly due to changing the delivery of content (ERTL), HEIs must consider economic, social and mental health factors that may exclude certain groups of students when designing these approaches. It is crucial to explore ways to facilitate remote learning for students that address epistemological access challenges while maintaining inclusivity and connectedness as this is likely to contribute positively to academic success.
Prevalence and Molecular Epidemiology of Bordetella pertussis Infection in South Africa
(University of the Witwatersrand, Johannesburg, 2024) Moosa, Fahima; Wolter, Nicole; du Plessis, Mignon
Pertussis remains a public health concern in South Africa, with increases in cases and outbreaks in recent years. We determined the incidence, transmission dynamics, serological attack rates and molecular epidemiology of B. pertussis in South Africa. Data from a longitudinal study enrolling individuals each year in 2016–2018 from two communities were used. Nasopharyngeal swabs were collected from participants twice-weekly and tested by real-time PCR. Serum was collected at 8 time points and tested using the anti-pertussis toxin IgG ELISA kit. Whole genome sequencing was performed on all available cultures (n=32) sourced from three additional surveillance programs between 2015–2019. Data were described and analyzed using univariate and multivariable regression models. Among 1684 participants, the incidence of B. pertussis was 0.21 (95% confidence interval 0.17–0.25) per 100 person-weeks. The mean duration of infection was 12 days (±standard deviation 19.1). Transmission of infection was more likely to occur from male index cases [adjusted odd ratio 12.20 (95%CI 1.57–94.96)], and individuals with ≥7 day’s infection duration [aOR 24.80 (95%CI 2.74–224.30)]. B. pertussis seroprevalence ranged from 1.8% to 5.2% across eight blood draws. The serological attack rate was 5.8% (87/1509), which was similar to the PCR attack rate (6.2%, 94/1509) (p=0.64). PCR-positive individuals aged 5–18 years (vs 19-44, aOR 6.8, 95% CI 1.3-35.1) and with episode duration of ≥7 days (vs <7 days, aOR 13.3, 95% vi CI 3.4-51.1) were more likely to seroconvert. For all individuals that seroconverted, the ≥4-fold rise in anti-PT IgG titer was detected by the next blood draw (mean: 2.9 months (range 3 weeks – 5.9 months). Using genome data, all isolates were identified as the globally-disseminated sequence type 2 and harbored the pertussis toxin promoter ptxP3. The dominant genotype was ptxP3-ptxA1-ptxB2-prn2-fimH2 (31/32, 96.9%), with no pertactin-deficient or other mutations in vaccine antigen genes identified. Within the community, despite a high incidence of B. pertussis, there was an overall low seroprevalence. Our data highlighted that increases in cases in South Africa are not likely due to evolutionary changes in the genome but potentially waning immunity due to the use of acellular vaccines and/or population immunity gaps.
Isolated nocturnal hypertension and target organ damage in a population of African descent
(University of the Witwatersrand, Johannesburg, 2024) Phukubje, Edgar Matome; Maseko, Muzi
The use of ambulatory blood pressure monitoring (ABPM) has revolutionised the approach to hypertension diagnosis and management. The ability to monitor blood pressure over a 24-hour period has enabled researchers to monitor blood pressure profile away from the doctor’s clinic, which has led to the diagnosis of various hypertension phenotypes like masked hypertension, isolated nocturnal hypertension (INH) and isolated daytime hypertension (IDH), and others. Previous studies have shown that night-time blood pressure is more closely related to target organ damage compared to daytime blood pressure. Since more studies indicate that people of African ancestry have elevated night-time blood pressure compared to other population groups, nocturnal blood pressure monitoring in this population group is crucial. However, there are few studies that have investigated the prevalence of INH, and their results are inconclusive. Hence the impact of INH on cardiovascular target organ damage is not well understood in this population group. It has been reported that dietary salt intake (DSI) has more severe cardiovascular outcomes in African populations compared to non-African populations groups because they are said to be salt sensitive. However, there are no studies that have investigated the relationship between 24-hour urinary salt excretion and 24-hour dipping patterns in populations of African ancestry. In addition, the impact of INH on target organ damage has never been compared to that of IDH. Hence, current intervention strategies primarily rely on daytime blood pressure to diagnose and treat hypertension. The relationship between age and blood pressure is well understood, but current studies have mainly focused on daytime blood pressure. The impact of age on nocturnal blood pressure is not well understood in this population group, and it is also unclear whether the age-related changes in nocturnal blood pressure translate to any cardiovascular target organ changes. Therefore, the aim of this study was to determine the relationship between INH and cardiovascular target organ damage in a South African population of African ancestry. A total 1600 participants above 18 years were recruited. These form part of the ongoing South African Hypertension and Diet Study in the Human Nutrition Research Laboratory. Office blood pressure was measured conventionally and through SpaceLabs ambulatory oscillometric monitors for 24-hours. Target organ function was determined through echocardiographic measurements and applanation tonometry using the sphygmocor device. 24-hour urine samples were collected to determine electrolyte excretion rates. Blood was collected when the participants visited the clinic. Only data with complete 24-hour ABPM matched with complete urinary collections were included for data analysis and the final sample was 796 participants. v Findings from the current study showed that 11% of the participants had INH, 13% had 24- hour sustained hypertension and 4% had IDH. The three groups had different dipping patterns. The sustained hypertensive group were non-dippers, IDH group were dippers, and the INH group had two dipping patterns: non-dipping (IND) and reverse dipping (IRD). Urinary electrolyte concentrations were significantly higher in IDH, and lower in INH. The INH group and 24-hour sustained hypertensives were the oldest cohort, while the NT and IDH were youngest. Pulse wave velocity (PWV) was significantly higher in the IND and IRD. The NT and IDH group had the lowest PWV. PWV in the INH was similar but not significantly different to the 24-hour sustained HT group. These findings indicate that the two INH subtypes (IND and IRD) damage large arteries to a similar effect as 24-hour sustained hypertension, while IDH does not cause any damage. The ABPM results were used to show changes in blood pressure with age. Different age group ranges were used, in increments of 10 years. Increased nocturnal blood pressure was associated with being older. Additionally, age-related changes in nocturnal blood pressure were associated with pre-clinical diastolic dysfunction. The current findings further show that blood pressure related cardiovascular target organ damage occurs during night-time in this population group. Urine analysis showed increased excretion in IDH and sodium retention in INH. Aldosterone levels were significantly higher in the INH, compared to 24-hour sustained HT group. Low aldosterone and salt retention increased nocturnal BP in the INH group. This means the current rise in the prevalence of cardiovascular disease in people of African descent despite increased efforts to diagnose and treat hypertension, is driven by INH, which remains undiagnosed because of the over reliance on conventional blood pressure measurement
The use of ultrasound compared to an age- based formula to estimate endotracheal tube size in an academic hospital
(University of the Witwatersrand, Johannesburg, 2024) Heslop, Donovan; Leonard, Tristan; Redelinghuys, Cara
Background An accurate estimation of tracheal diameter for endotracheal tube size selection is imperative in the pediatric population, with ultrasound shown to be an acceptable and superior method of endotracheal tube size estimation when compared to conventional age-based methods. Aim To compare the accuracy of endotracheal tube size estimation using airway ultrasound to age-based formula in the South African pediatric population. Methods This was a prospective observational study, with 54 patients, American Society of Anesthesiologists physical status I–III, aged two to 12 years old, scheduled for elective surgery at Chis Hani Baragwanath Academic Hospital, South Africa. Patients were allocated to two groups, the age-based method group or ultrasound method group. The accuracy of each method used for endotracheal tube estimation was assessed using a standardized leak test. Post intubation endotracheal tube cuff pressures were measured and post operative follow up was done to assess for features of airway injury. Results The ultrasound method was a more accurate estimate of endotracheal tube size (74.47%) compared to the age-based method (29.63%) (p = 0.0011). In all cases a cuffed endotracheal tube was used. No difference was seen between the mean endotracheal tube cuff pressure between the groups with a large proportion of patients having underinflated endotracheal tube cuffs. Conclusion Ultrasound is a more accurate predictor of appropriate ETT size in the pediatric population compared to a conventional age-based formula. The use of ultrasound for the estimation of ETT size is an accurate, non-invasive, and reproducible technique with potential for long-term cost saving and reduced complications. Ultrasound is iii becoming readily accessible in the theatre setting in South Africa and with appropriate training and expertize, this bedside tool has the potential for more widespread uptake and may be a more accurate means of determining endotracheal tube size in children.
Design of a Smart, Stealth Nano-system for Targeted Drug Delivery in Prostate Cancer Treatment
(University of the Witwatersrand, Johannesburg, 2024) Essa, Divesha; Kumar, Pradeep; Choonara, Yahya E.
There have been several polymeric drug delivery vehicles developed on the nanoscale for chemotherapeutic applications. However, the use of polymers without the implementation of design perspectives has led to limitations in efficacy, including rapid elimination, poor biocompatibility, and high off-site delivery of the therapeutic agent. In this study we developed polymeric nanoparticle systems with enhanced cell penetrating and targeting abilities with the aid of design and optimization. The ultimate goal was to fabricate an optimized system with improved properties and performance as a nanocarrier for the chemotherapeutic drug docetaxel to prostate cancer tissue. Poly (lactic-co-glycolic) acid provided the ideal polymeric matrix to entrap hydrophobic drugs with high efficacy. Chitosan provided a positively charged surface to the system, ensuring favorable interactions with negatively charged cell membranes. Poly ethylene glycol provided a shielding effect to increase in vivo residence time, while folate and anti-PSMA antibody acted as targeted ligands to bind to prostate specific membrane antigen, PSMA, a cell surface receptor that is overexpressed on prostate cancer cells. Fabrication approaches compared traditional and microfluidics-based method, and we were able to prepare uniform, reproducible nanoparticles using microfluidics. We used disulfiram and the plant- based bioactive quercetin as model bio-actives, and investigated chitosan and folic acid for their reported cell penetrating properties, using a design of experiments optimization. Finally, we used the drug docetaxel, with PLGA and PEG as matrix polymers and anti-PSMA antibody as a targeting ligand for its specific ability to bind to PSMA. All systems were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA), and X-ray powder diffraction (XRD). Drug loading and release were conducted by ultra-violet (UV) spectroscopy and high-performance liquid chromatography (HPLC). Using the microfluidics method and an intermediate PEG density, the disulfiram encapsulated nanoparticles were prepared with a size of 179±2.5 nm and maximum drug release of 70%. The targeted systems loaded with quercetin or docetaxel both displayed sustained pH dependent release profiles with maximum release of 78% quercetin and 72% of docetaxel at the tumour microenvironment- relevant acidic pH of 6. We evaluated in vitro toxicity of these systems on PSMA positive (LnCap) and negative (PC-3) cell lines as well as on a non-cancerous cell line (NIH-3T3), and thereafter conducted comparative fluorescence-based cellular uptake studies. Both targeted systems demonstrated higher cellular uptake in LnCap and an increase in toxicity of 66% for the quercetin-loaded and 60% for the docetaxel-loaded systems on LnCap compared to PC-3. The anti-PSMA targeted docetaxel-loaded system also selectively caused cell cycle arrest and 89,4±8,4% inhibition of cell migration in LnCap cells, but no inhibition on PC-3 cells, suggesting a PSMA-specific mechanism of action in these processes. Finally, we used an in vitro 3D LnCap multicellular tumour spheroid model to test for anti- cancer efficacy of the prepared docetaxel loaded nano-systems, and an in vivo nude mouse model to evaluate its biocompatibility. There was significantly more inhibition of spheroid growth by the non- targeted system (18,3±5,7%) and the targeted system (50,4±3,3%) compared to the untreated group after fifteen days of treatment, while all treatments showed no toxicity on the major organs of nude mice. Further studies are required to explore the potential of the PSMA targeted nano-system for its in vivo anti-cancer therapeutic potential.
Utilisation of maternal, newborn and child healthcare services in three sub-Saharan African countries (DRC, Kenya, and Tanzania) using Demographic Health Surveys data from 2007-2016: Application of Generalised Structural Equation and Machine Learning Models
(University of the Witwatersrand, Johannesburg, 2024) Mlandu, Chenai; Musenge, Eustasius
Background: The risk of child deaths within the first month of life is elevated than the later stages of childhood. Globally, Sub-Saharan Africa (SSA) has the highest neonatal mortality. Majority of the countries in SSA including the DRC, Kenya and Tanzania are struggling to meet Sustainable Development Goal (SDG) 3.2 of reducing the neonatal mortality rate to 12 deaths per 1,000 live births by 2030 (2). Most causes of neonatal deaths are preventable and treatable. Universal coverage, timely and effective utilisation of maternal, newborn, and child healthcare (MNCH) services during pregnancy, delivery, and postpartum has the potential to save many lives of newborns in high-burden countries. vii Antenatal care (ANC) is the first service offered to pregnant women in MNCH. The timing and frequency of ANC visits is critical for the mother and her unborn child. The WHO recommends that women initiate ANC within 16 weeks of pregnancy and attend a minimum of four ANC visits for timely and optimum care before delivery (3, 4). The WHO also recommends that pregnant women receive assistance from a skilled worker during delivery and get postnatal checks with their newborns within 6 weeks of delivery (5, 6). Furthermore, utilising the Continuum of Care (CoC) for MNCH could significantly reduce maternal and newborn deaths in SSA. In the context of MNCH, the CoC is an approach that ensures continuous care from the period of pregnancy, through to childbirth, postnatal period, infancy, and the childhood period (7). Despite the recognition of the use of vital services in MNCH, timely and adequate uptake of MNCH services remains poor and the coverage of MNCH is far from universal in SSA. Most pregnant women initiate ANC after 16 weeks and hence fail to receive timely ANC interventions (8). Uptake of ANC visits, skilled birth attendance (SBA) and postnatal care (PNC) is suboptimal (8-11). Studies in SSA have explored various factors associated with MNCH services utilisation, however, our understanding of MNCH services utilisation in SSA is still limited. Trends in utilisation of MNCH services over time such as late ANC uptake have not been thoroughly assessed. Late uptake of ANC is still a common problem in SSA. Tracking women’s progress in the timing of ANC will ascertain if they are any changes in women’s late uptake of ANC and the contributing factors. This information will guide future policies and programmes which focus on improving the timely uptake of ANC in the SGD era. There is also a dearth of empirical evidence on the factors associated with the utilisation of ANC, skilled delivery and postnatal care in the CoC using nationally representative data. The CoC views both the mother and child as a collective rather than as separate/ individual entities. Understanding factors that viii contribute to the full utilisation of drop out from the CoC is essential for the formulation of interventions than enhance the CoC. Furthermore, studies which investigated either the individual utilisation of MNCH services such as timing of ANC, ANC visits, SBA and PNC services or the CoC have tended to use more of the traditional analysis methods such as the logistic regression. The application of more versatile analysis methods such as Machine Learning is not common. Machine Learning methods are capable of extracting information that commonly used methods (logistic regression) fail to do by uncovering hidden patterns and relationships, particularly in large data sets (12). The application of Machine Learning methods can offer opportunities of enhancing existing methods (conventional regression methods) for predicting and classifying MNCH utilisation leading to more effective interventions to improve MNCH utilisation. There is also a limited understanding on the interrelationships between MNCH services utilisation and neonatal outcomes. The associations between MNCH services utilisation and newborn outcomes such as neonatal mortality are commonly assessed using traditional approaches that assume direct associations. Specific analytical methods, such as Generalised Structural Equation Modeling (GSEM) can be used to model complex relationships such as interrelated links between utilisation of different MNCH services and neonatal outcomes. GSEM gives a clear understanding of how different services of MNCH are related to one another with neonatal outcomes by estimating both direct and indirect paths associations for more effective targeted interventions. Given the critical role of MNCH in ending preventable neonatal mortality, the overarching aim of this study was to describe the utilisation of MNCH services and their associations with neonatal mortality using GSEM and Machine Learning models in three sub-Saharan African countries: the DRC, Kenya, and Tanzania. ix Methods: The study utilised cross-sectional secondary data of reproductive-age women from the Democratic Republic of Congo (DRC) (2007-2013/14), Kenya (2008-2014) and Tanzania (2010-2015/16) Demographic Health Surveys. Firstly, the multivariate logistic regression analysed factors associated with late ANC initiation accounting for clusters, survey weights and stratification for the different rounds of the Demographic Health Surveys. Trends in late initiation of ANC over time in each country were assessed by comparing the earlier and later surveys using differences in prediction scores (prediction probabilities generated after running the multivariate logistic regression models). Secondly, the study assessed the main predictors of non-utilisation of PNC using the Decision Tree. The model performance of the Decision Tree was compared to the Logistic Regression using Accuracy, Sensitivity, Specificity and area under the Receiver Operating Characteristics. Thirdly, factors associated with the drop out from the MNCH continuum, defined as not fully utilising either ANC, SBA, or PNC services, were analysed using multivariate logistic regression accounting for clusters, survey weights and stratification. Machine Learning analysis was used to predict the drop out from the MNCH continuum using features (predictors) that were found significant in the multivariate logistic regression. Five classification Machine Learning models were built and developed including the Artificial Neural Network, Decision Tree, Logistic Regression, Random Forest and Support Vector Machine to predict the drop out from the MNCH continuum. The prediction accuracies of the models were then compared using parameters including Accuracy, Precision, Recall, Specificity, F1 score and area under the Receiver Operating Characteristics. Fourthly, the Generalised Structural Equation Modeling (GSEM) was used to assess the mediatory role of MNCH services utilisation on neonatal mortality. The endogenous variables x were ANC attendance, SBA and PNC attendance, low birth weight and neonatal mortality. The GSEM analysis also accounted for survey weights and considered cluster random effects. Results: The findings showed a reduction in late ANC initiation (67.8%-60.5%) between 2008-2014 in Kenya as well as in Tanzania (60.9%-49.8%) between 2010-2016, but an increase was observed in the DRC (56.8%-61.0%) between 2007-2014. In the DRC, higher birth order was associated with ANC initiation delays from 2007-2014, whilst rural residency, lower maternal education and household income was linked to ANC initiation delays in 2014. In Kenya, lower maternal education and household income was associated with ANC initiation delays from 2008-2014, whilst rural residency and increased birth order were linked to ANC initiation delays in 2014. In Tanzania, higher birth order and larger households were linked to ANC delays from 2010-2016, whilst ANC initiation delays were associated with lower maternal education in 2010 and lower-income households in 2016. The results also showed that the Decision Tree models had higher prediction accuracy of non- utilisation of PNC than the Logistic Regression models. Using the Decision Tree, low quality of ANC, home deliveries and unemployment were associated with the highest probability of not utilising PNC (92.0%) in the DRC. In Kenya, home deliveries, unemployment and lack of access to mass media were associated the highest likelihood of not utilising PNC (87.0%). In Tanzania, home deliveries, low quality of ANC and unwanted pregnancies exhibited the highest likelihood of not utilising PNC (100.0%). The results also revealed very high rates of dropping out from the MNCH continuum in the DRC (91.0%), in Kenya (72.3%) and Tanzania (93.7%). Rural residence, lower maternal education and non-exposure to mass media were common predictors of dropping out from the MNCH continuum across the three countries. Further, the influence of factors such as xi household wealth, household size, access to money for medication, travel distance to health facilities, and parity and maternal age varied by country. Results from the Machine Learning analysis showed that the Logistic Regression had the least prediction accuracy, while the Random Forest exhibited the highest prediction accuracy. Using the Random Forest, the study further ranked the most important predictors of the drop out from the MNCH continuum. Household wealth, place of residence, maternal education and exposure to mass media were the top four most important predictors. The results also showed direct and indirect associations between MNCH services utilisation and neonatal mortality. ANC attendance mediated the total effects of PNC attendance on neonatal mortality by 8.8% in Kenya and 5.5% in Tanzania. ANC attendance and SBA also sequentially mediated the total effects of PNC attendance on neonatal mortality by 1.9% in Kenya and 1.0% in Tanzania. The results in Tanzania also showed ANC attendance mediated 2.8% of the total effects of LBW on neonatal mortality. No presence of mediation was observed in the DRC; however, ANC attendance moderated the relationship between parity and neonatal mortality. Conclusions: The study found that late uptake of ANC decreased between the two survey rounds in Kenya and Tanzania but increased in the DRC. Women from various geographic, educational, parity, and economic groups showed varying levels of late ANC uptake. Increasing women’s access to information platforms and strengthening initiatives that enhance female education, household incomes, and localise services may enhance early ANC uptake. The Decision Tree models showed higher prediction accuracy of non-utilisation of PNC than the Logistic Regression models in the DRC, Kenya and Tanzania. Using the Decision Tree, women who had poor quality of ANC, home deliveries, unemployment, unplanned pregnancies, and no mass media access were identified as high-risk subpopulations of non- xii utilisation of PNC. Improving access and quality of care, incorporation of TBAs into the formal health systems, government health financing, increasing access to mass media and integrating maternal healthcare services with family planning services should be considered as top priority interventions to improving the utilisation of PNC. Most women and children drop out of the MNCH continuum in the DRC, Kenya and Tanzania. Rural residence, lower maternal education and non-exposure to mass media were common factors linked to the high dropout in the MNCH continuum. The use of Machine Learning can help support evidence-based decisions in MNCH interventions. Rapid response mechanisms such as web-based applications can also be developed through the use Machine Learning whereby a pregnant woman’s future utilisation of the services in CoC is assessed and monitored in real-time. The GSEM findings showed interconnections between MNCH services utilisation such as timing of ANC, ANC visits, SBA, PNC and neonatal mortality. This suggests that more than direct and indirect factors are accountable for the associations between MNCH services utilisation and neonatal mortality. The mediation role of MNCH services on neonatal mortality indicates critical areas for targeted interventions to reduce neonatal mortality. Overall, the study aimed to describe the utilisation of the MNCH services and associations with neonatal mortality in the DRC, Kenya and Tanzania. The study showed declines in late ANC uptake in two countries, however, early uptake of ANC is far is still not universal. The study also showed very low levels of retention in the CoC, and most women and children drop out in the CoC at postpartum period. The findings also showed the existence of social, health system and individual inequalities in MNCH and their impact on early childhood survival. Women who are vulnerable to unequal and poor MNCH services utilisation are characterised by poverty, rural residence, long travel distances to health facilities, unaffordable medical expenses, home deliveries, low quality of xiii care, low education, high parity, younger age, unemployment, limited exposure to mass media, and unplanned pregnancies. Context-specific intervention programs such as female education, government health financing, MNCH promotion programs through mass media and improved accessibility and quality of care in health facilities, particularly for the most vulnerable groups of the populations such as women of low socioeconomic status and women from underserved rural areas are essential to improve the overall health of mothers and children and meeting the SDG-3 goals. Modern biostatistical models like Machine Learning provide essential tools to understand public health problems. These techniques should be applied to complement the conventional statistical methods, particularly the tree-based models like the Decision Tree and Random Forest for predicting and classifying the utilisation of MNCH services. The GSEM established interconnections between timing of ANC, ANC visits, SBA and PNC and neonatal mortality. The timing of the first ANC contact is an important starting point to a continuation through the COC. It makes women better informed about pregnancy and the subsequent use of MNCH services. All stakeholders should work more on promoting early uptake of ANC by setting up initiatives that increase women’s access to information platforms, enhance female education, improve household incomes, and bring services closer to communities.
Developing an Intervention to Improve Informed Decision-Making for Oncology Patients in South Africa
(University of the Witwatersrand, Johannesburg, 2024) Blanchard, Charmaine Louise; Norris, Shane
Introduction Patients making cancer treatment decisions face several challenges including grappling with difficult terminology and deliberating different options based on the information provided and their own values while experiencing high levels of stress. Informed cancer decision making by South African patients in the public healthcare sector, is further complicated by the constrained resources in the oncology clinics limiting the time available for consultations with the oncologists. Language and socio-cultural barriers impact on the patient’s ability to make fully informed treatment decisions, which are legally and ethically required. While decision aids (DAs) exist in high income countries (HICs) to assist patients to make informed cancer treatment decisions, there are no studies reporting the development of cancer treatment DAs in South Africa. Aim The aim of this thesis was to develop a decision support intervention (DESI) to improve cancer patient informed treatment decision making. Methods This thesis applied the Intervention Mapping (IM) framework to the development of the DESI. The three objectives of the thesis related to the first step of the IM process namely a needs assessment to develop the logic model of the problem. The first objective was to assess the effectiveness of decision aids (DAs) in addressing vulnerable patient-reported decision needs by conducting a mixed methods systematic review to understand the synergies and gaps between the DAs and the patients’ needs. For the second objective a quantitative study was undertaken to measure the South African patient’s health literacy (HL), factors associated with HL, their decision control preferences (DCPs), and to assess their decision needs. The study enrolled 124 patients diagnosed with cancer at three tertiary level oncology clinics in South Africa (two in Gauteng and one in KwaZulu Natal). For the third objective a qualitative study was undertaken to understand the patient experiences of making cancer treatment decisions and the oncology staff perceptions of the decision- making process. In-depth interviews with 30 patients and eight focus groups with oncology staff were conducted at the same clinical sites as the quantitative study. The results of the XVII three studies were triangulated to provide a logic model of the problem which informed the next steps of the IM process, resulting in an evidence-based theory driven intervention program. Results The systematic review identified significant gaps between the DAs and the vulnerable patients’ decision support needs, particularly relating to communication in the consultation and providing counselling and coaching support for decision-making. The 124 South African patients at the study sites in Gauteng and KwaZulu Natal had mostly marginal (69%) to limited (11%) health literacy, positively associated with their level of education (OR 2.2, 95% CI 0.58 – 8.55 for high school and OR 14.6 95% CI 2.2 – 96.61 for tertiary education) and socio-economic status (OR 4.1, 95% CI 1.03 - 15.98, for the wealthiest tertile). The patients reported high information needs (71%) despite reporting understanding a lot of what the doctors explained (77%) and feeling comfortable a lot, asking questions (82%) in the consultation. Most patients (82%) preferred an active decision-making role. The qualitative study findings confirmed the high levels of information needs, but most patients did not ask questions in the consultation and often played a passive role in decision-making. Language and cultural differences between the patients and the oncologists were identified by oncology staff as major barriers to informed decision-making, and support from the patients’ families, the oncology nurses and the palliative care teams addressed some of the patients’ decision needs. Following the logical, iterative process of the IM framework a locally relevant decision support intervention program was developed. Conclusion Patients have high levels of cancer and treatment information needs and wish to be active participants in their treatment decision making yet often lack the self-efficacy to engage in treatment deliberation with their oncologists. Language and cultural discordance between the patient and oncologist compounded by the time pressures of the clinic, are barriers to effective patient-centred communication in the consultation. It is vital that adequate training is provided to oncologists to improve culturally sensitive patient-centred communication when supporting cancer patients to make informed treatment decisions.

3. Electronic Theses and Dissertations (ETDs)

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