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A contaminated regression model for count health data
(Sage, 2025-02) Otto, Arnoldus F.; Ferreira, Johannes Theodorus; Tomarchio, Salvatore Daniele; Bekker, Andriette, 1958-; Punzo, Antonio; arno.otto@up.ac.za
In medical and health research, investigators are often interested in countable quantities such as hospital length of stay (e.g., in days) or the number of doctor visits. Poisson regression is commonly used to model such count data, but this approach can’t accommodate overdispersion—when the variance exceeds the mean. To address this issue, the negative binomial (NB) distribution (NB-D) and, by extension, NB regression provide a well-documented alternative. However, real-data applications present additional challenges that must be considered. Two such challenges are (i) the presence of (mild) outliers that can influence the performance of the NB-D and (ii) the availability of covariates that can enhance inference about the mean of the count variable of interest. To jointly address these issues, we propose the contaminated NB (cNB) distribution that exhibits the necessary flexibility to accommodate mild outliers. This model is shown to be simple and intuitive in interpretation. In addition to the parameters of the NB-D, our proposed model has a parameter describing the proportion of mild outliers and one specifying the degree of contamination. To allow available covariates to improve the estimation of the mean of the cNB distribution, we propose the cNB regression model. An expectation-maximization algorithm is outlined for parameter estimation, and its performance is evaluated through a parameter recovery study. The effectiveness of our model is demonstrated via a sensitivity analysis and on two health datasets, where it outperforms well-known count models. The methodology proposed is implemented in an R package which is available at https://github.com/arnootto/cNB.
Using interactive SMS support groups to prevent mother-to-child HIV transmission in South Africa : a qualitative analysis of social and psychological benefits
(Taylor and Francis, 2025-12) Crusto, Cindy A.; Pittenger, Samantha; Costeines, Jessica; Amutah-Onukagha, Ndidiamaka; Kydd, Anna; Visser, Maretha; Do, Thu; Dean, Andrea; Forsyth, Brian
Although advances have been made in the prevention of mother-to-child transmission (PMTCT) of HIV, social and psychological factors associated with learning of an HIV diagnosis and living with HIV during pregnancy can impact medication adherence and health outcomes. Mobile technology can increase social support; however, it is unclear if such technology can be used to provide social support to reduce negative psychological outcomes. This study analysed the feasibility of conducting a multi-way interactive SMS-based support group with HIV-positive women in the PMTCT programme in clinics of Tshwane, South Africa. We studied the types of social support women received through using this mobile technology to address personal, interpersonal and social barriers to PMTCT adherence. We analysed the social and psychological content of SMS messages sent between seven HIV-positive pregnant women participating in a 12-week interactive support group. We conducted a qualitative, thematic analysis of the 734 text messages. Five social/psychological themes emerged: appraisal and emotional support, informational support, spiritual support, acceptance and disclosure of HIV status, and gratefulness for the support group, suggesting benefits of the interactive SMS-based support group. This interactive support model can provide social support and information to pregnant women living with HIV, leading to a reduction in isolation and negative psychological outcomes which could promote positive health outcomes.
The mediating role of self-esteem and mental wellbeing in the association between emotional intelligence and motivation among Saudi nursing students
(Sage, 2025-07) Albagawi, Bander Saad; Alsalamah, Yasir S.; Dabosi, Shahd; Alharbi, Maryam Saad; Alkharji, Sara A.; Alrawili, Rakan Mansuor; Babkair, Lisa; Fawaz, Mirna
INTRODUCTION : Much emphasis has been placed on the critical role that emotional intelligence plays in influencing university students’ motivation to learn.
OBJECTIVE : The current investigation examined the link that exists between emotional intelligence and learning motivation among Saudi undergraduate nursing students, as well as the mediating and moderating effects that mental well- being and self-esteem perform in this association.
METHODS : A quantitative cross-sectional methodology was used in the research, which recruited 367 Saudi undergraduate nursing students.
RESULTS : The results of the ANOVA and Welch F-test showed that the level of self-esteem was correlated with emotional intelligence and mental wellbeing scores, but not with motivation scores. Upon conducting structural equation modeling, significant direct effect pathways were identified between emotional intelligence, mental wellbeing, and motivation. Only indirect pathways were identified between self-esteem and motivation.
CONCLUSION : This study indicates that mental wellbeing mediates the link between emotional intelligence and motivation to learn, where self-esteem operates as a significant moderator. Thus, safeguarding the wellbeing of the students should be prioritized to enhance their academic journey and educational outcomes. The results of this investigation offer several recommendations for nursing education, highlighting the importance of emotional intelligence in promoting motivation in academic settings and, therefore, academic achievement.
Traditional ecological knowledge in indigenous hunting body cultural research as an emerging collaborative self-governing approach for green ethical cultural advocacy as protected belief status
(Sage, 2025-07) Fang, Wei-Ta; Nwachukwu, Precious Toby T.; Lin, Nikky; Lee, Chien-Shing
The gaps in the literature and the nonexistence of restrictions from present-day legislation are the bane of Traditional Ecological Knowledge (TEK) in hunting cultural practice. This research explores and engages qualitative research by applying visual and dictated information on hunting body culture transformation for indigenous ecological knowledge. Ethical and greening advocacy an emerging collaborative framework for hunting activities through the eyes and experience of the aboriginal people of Taiwan was used to explore the relationships between TEK and self-governing management to grasp and experience the meaning of Hunting Body Culture (HBC). Twelve activities of Taiwan’s Gaga aboriginal hunting behaviors from longitudinal research from 2012 to 2024 were observed by reading hunting photo-voice information and interviewing fourteen aboriginal hunters. The findings include the utilization of Green Ethical Cultural Advocacy (GECA) to reflect the study’s outcomes on social norms, hunting harvest patterns, hunting ritual events, forming of hunting groups, the choice of hunting tools, game selection differences, personalized attributes like solitude; and generic tolerance for indigenous cultural heritage as a Protected belief transforming toward a legislative Protected Status. Future research should triangulate positivist/interpretive and mixed approaches to navigate the ethical justice pattern for TEK and the use of digital technology to administer greening ethical cultural advocacy in hunting. The implications of the research to theory and practice were specified, as we proposed four distinctive principles for green hunting.
PLAIN LANGUAGE SUMMARY
This study engaged a qualitative research approach by applying visual and dictated information to explore hunting body culture transformation for indigenous ecological knowledge. Twelve activities of Taiwan’s Gaga aboriginal hunting behaviors from longitudinal research from 2012 to 2024 were observed by reading hunting photo-voice information and interviewing fourteen aboriginal hunters. This research’s findings include using of green cultural ethical advocacy to reflect the study’s outcomes on social norms, hunting harvest patterns, hunting ritual events, forming of hunting groups, the choice of hunting tools, game selection differences, personalized attributes like solitude; and generic tolerance for indigenous cultural heritage as a protected belief.
Advances in hypothyroidism management : rethinking therapy beyond levothyroxine
(Medpharm Publications, 2025-10) Ditshego, Rebotile; Pick, Jessica; Ncube, Keith Ntokozo; keith.ncube@up.ac.za
Hypothyroidism, a prevalent neuroendocrine disorder characterised by insufficient thyroid hormone production and a wide spectrum of clinical manifestations, affects approximately 5% of the population, with an additional 5% remaining undiagnosed. While levothyroxine remains the golden standard of care, its inability to resolve persistent symptoms in a subset of patients highlights the need for alternative approaches. Combination levothyroxine+liothyronine therapy, though unpopular and underutilised by most physicians, offers potential benefits, particularly when tailored to mimic natural thyroid hormone ratios. Furthermore, emerging therapies show promise in reducing pharmacokinetic fluctuations that limit current advances in hypothyroidism therapy. By addressing the shortcomings of traditional therapies, these innovative approaches aim to improve the quality of life and clinical outcomes for patients with hypothyroidism, especially when the golden standard fails. This review highlights current viable options and explores emerging therapeutic strategies that could potentially optimise current treatment and quality of life, catering for all hypothyroidism patients.