Masters Degrees (Epidemiology and Biostatistics)
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- ItemQuality of systematic reviews in African emergency medicine : a cross-sectional methodological study(Stellenbosch : Stellenbosch University, 2023-03) Van Niekerk, Hendrik Jacques; McCaul, Michael; Rohwer, Anke; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Global Health. Epidemiology and Biostatistics.ENGLISH SUMMARY: Introduction: Reliable systematic reviews are essential to inform clinical practice guidelines, policies and further research priorities in Africa. For systematic review findings to be trustworthy, they need to be conducted with methodological rigour and reported transparently. We assessed the methodological quality of systematic reviews published in African emergency medicine journals, comparing them to those published in international emergency medicine journals. Additionally, we describe the types of review literature published in the African journals. Methods: We performed a cross-sectional methodological study of systematic reviews published in selected African and international emergency medicine journals from 2012 to 2021. Studies were eligible for inclusion if they were i) published in one of the top five emergency medicine journals in the African region or internationally, ii) a review article on an emergency medicine topic and iii) published between January 2012 and December 2021 in English or French. We searched PubMed, Web of Science and Scopus databases and hand-searched selected journals. Two authors screened titles, abstracts and full texts independently and in duplicate to select reviews for inclusion. Data extraction was performed by one reviewer, using a standardised form, after completing a calibration exercise. We described the characteristics of systematic reviews and assessed methodological quality using AMSTAR II. Results: We identified 34 (37%) African and 511 (54%) international systematic reviews from 92 and 948 review articles respectively across 10 journals. We included all 34 African and a random sample of 100 international systematic reviews. Methodological quality was low or critically low for all the African systematic reviews (n=34, 100%) and all but three international systematic reviews (n=97, 97%). The median number of critical domain weaknesses was 4 (IQR 4;5) and 2 (IQR 2;4) for African and international systematic reviews respectively. The most common weaknesses across both African and international systematic reviews were i) not establishing a priori review protocols, ii) unclear selection of study designs iii) not providing a list of excluded studies and iv) unclear reporting on funding sources for included studies. Conclusion: Emergency medicine systematic reviews published in African and international journals are lacking in methodological quality. Reporting an a priori protocol, developing a comprehensive search strategy, appropriate evidence synthesis and adequate assessment of the risk of bias, heterogeneity and evidence certainty will improve the quality of systematic reviews.
- ItemTranslation and validation of the Shona version of the exercise benefits and barriers scale in Zimbabwean adult people living with HIV/AIDS : a cross-sectional study(Stellenbosch : Stellenbosch University, 2023-03) Dambi, Jermaine Matewu; Esterhuizen, Tonya; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Global Health. Epidemiology and Biostatistics.ENGLISH SUMMARY: Objectives: Despite the widely known benefits of physical activity (PA), only 25% of people living with HIV (PLHIV) meet the WHO-recommended minimum PA levels. With the need to promote PA, there is a need to objectively measure PA, including understanding context-specific barriers, facilitators, and general awareness of the importance of PA. This study aimed to translate and validate the Shona version of the Exercise Benefits and Barriers Scale (EBBS) in Zimbabwean PLHIV. Design: cross-sectional study. Setting: Four (4/9) randomly selected polyclinics (primary healthcare facilities) in urban Harare, Zimbabwe. Participants: We recruited adult patients (aged ≥ 18 years) with a confirmed diagnosis of HIV. Participants had to be willing to provide informed consent, not acutely unwell and requiring emergency treatment, and proficient in the Shona language. Interventions: We used a forward-backwards translation method to translate the EBBS from English to Shona, a Zimbabwean native language. The alpha EBBS-Shona version was pilot tested on 10 PLHIV to assess the face validity, understandability and cultural appropriateness using semi-structured interviews. Thereafter, the EBBS was administered to 567 consecutively selected PLHIV. Results: Most participants were female (72.5%) and self-reported having secondary/high school education (78.8%), with a mean age of 39.9 (SD 12.1) years. The EBBS-Shona version yielded a four factor solution consisting of three benefits factors and one barrier factor against the originally postulated six-factor structure. The EBBS-Shona yielded α=0.85 and intraclass correlation coefficient= 0.86, demonstrating excellent reliability. Increased perception of exercise benefits was positively correlated with increased reports of physical activity, higher health-related quality of life and lower psychiatric morbidity; evidence for construct validity. Conclusions: This study demonstrates the validity and reliability of the EBBS-Shona version in Zimbabwean PLHIV. The EBBS-Shona version can be used for research and clinical purposes to glean data to inform the development, implementation, and evaluation of bespoke PA interventions for PLHIV. Strengths and limitations of this study: • Application of a robust translation and adaption methodology • Utilisation of both exploratory and confirmatory factor analysis for structural validation • Recruitment of a large sample size • Electronic data collection negating missing responses • Non-random, facility-based recruitment of study participants
- ItemQuality of systematic reviews in African emergency medicine : a cross-sectional methodological study(Stellenbosch : Stellenbosch University, 2023-03) Van Niekerk, Jacques; Fapohunda, Tomiwa; Rohwer, Anke; McCaul, Michael; Rohwer, Anke; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Global Health. Epidemiology and Biostatistics.ENGLISH SUMMARY: Introduction: Reliable systematic reviews are essential to inform clinical practice guidelines, policies and further research priorities in Africa. For systematic review findings to be trustworthy, they need to be conducted with methodological rigour and reported transparently. We assessed the methodological quality of systematic reviews published in African emergency medicine journals, comparing them to those published in international emergency medicine journals. Additionally, we describe the types of review literature published in the African journals. Methods: We performed a cross-sectional methodological study of systematic reviews published in selected African and international emergency medicine journals from 2012 to 2021. Studies were eligible for inclusion if they were i) published in one of the top five emergency medicine journals in the African region or internationally, ii) a review article on an emergency medicine topic and iii) published between January 2012 and December 2021 in English or French. We searched PubMed, Web of Science and Scopus databases and hand-searched selected journals. Two authors screened titles, abstracts and full texts independently and in duplicate to select reviews for inclusion. Data extraction was performed by one reviewer, using a standardised form, after completing a calibration exercise. We described the characteristics of systematic reviews and assessed methodological quality using AMSTAR II. Results: We identified 34 (37%) African and 511 (54%) international systematic reviews from 92 and 948 review articles respectively across 10 journals. We included all 34 African and a random sample of 100 international systematic reviews. Methodological quality was low or critically low for all the African systematic reviews (n=34, 100%) and all but three international systematic reviews (n=97, 97%). The median number of critical domain weaknesses was 4 (IQR 4;5) and 2 (IQR 2;4) for African and international systematic reviews respectively. The most common weaknesses across both African and international systematic reviews were i) not establishing a priori review protocols, ii) unclear selection of study designs iii) not providing a list of excluded studies and iv) unclear reporting on funding sources for included studies. Conclusion: Emergency medicine systematic reviews published in African and international journals are lacking in methodological quality. Reporting an a priori protocol, developing a comprehensive search strategy, appropriate evidence synthesis and adequate assessment of the risk of bias, heterogeneity and evidence certainty will improve the quality of systematic reviews.
- ItemKnowledge of male partner HIV status as a risk factor for HIV indicators in women using prevention of mother-to-child transmission of HIV services in WHO priority countries : a systematic review and meta-analysis(Stellenbosch : Stellenbosch University, 2022-12) Mmotsa, Tshiamo Moshading; Ngandu, Nobubelo K.; Adetokunboh, Olatunchi O.; Nyasulu, Peter; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Global Health. Epidemiology and Biostatistics.ENGLISH SUMMARY: Elimination of new maternal and infant Human Immunodeficiency Virus (HIV) cases has been a top global priority and various targets have been introduced to end HIV in pregnant, postpartum women and their infants. To achieve these targets, it is important to understand factors related to unfavourable outcomes in the prevention of mother-to-child transmission of HIV (PMTCT, MTCT) programme cascade. The role of a male partner, especially HIV status non-disclosure is one of several important factors. Our study aimed to determine whether not knowing a male partner’s HIV status was a significant risk factor for HIV indicators, including poor HIV clinical outcomes, among pregnant, postpartum women and their infants in the 21 World Health Organization (WHO) priority countries for eliminating MTCT. We conducted a systematic review and meta-analysis of literature through four electronic databases in April 2022 for eligible studies from the 21 WHO priority countries. We included observational studies examining male partner HIV status non-disclosure as a risk factor for HIV indicators in pregnant, postpartum women and their infants conducted after the implementation of the Option B+ treatment policy (i.e., lifelong antiretroviral therapy (ART) regardless of clinical disease status) were included. We conducted a meta-analysis for studies without heterogeneity and assessed the certainty of the evidence assessed using Grading of Recommendations Assessment, Development, and Evaluation (GRADE) for each outcome. Forty-six full-text articles were screened and only three articles were included. The included studies were cross-sectional and retrospective cohort studies, conducted in Malawi, South Africa, and Uganda, with a total of 5248 participants. Sub-optimal ART adherence was significantly greater among women who did not know their male partner’s HIV status compared to those who knew the partner’s HIV status (2 studies; n= 3263: Odds ratio (OR) 1.85; 95% confidence interval (CI) 1.49–2.29; P <0.01) with no significant heterogeneity (P = 0.72; I2 = 0%). Complete ART adherence was significantly less among women who did not know their male partner’s HIV status compared to those with knowledge of the partner’s HIV status (1 study; n= 465: OR 0.47; 95% CI 0.32 – 0.69). MTCT was not significantly associated with male partner HIV status non-disclosure (1 study; n= 2881: OR 1.35; 95% CI 0.84 – 2.15). The certainty of evidence from all the studies was low for all outcomes. We found that there was limited evidence to fully understand the role a male partner’s HIV status disclosure plays in the PMTCT cascade. The available studies showed that the likelihood of ART non-adherence was increased by not knowing a male partner’s HIV status, therefore, highlighting the importance of knowing a male partner’s HIV status in the PMTCT cascade. We could not explore the other HIV indicators i.e., MTCT and other clinical outcomes due to the limited and non-availability of primary studies. More and appropriately designed studies within the WHO priority countries are needed urgently to inform policies and interventions for improving male partner involvement. These studies should also include a clear definition of male partner involvement which also highlights HIV testing and male partner disclosure.
- ItemA prediction risk score for HIV among adolescent girls and young women in South Africa : identifying those in need of HIV pre-exposure prophylaxis(Stellenbosch : Stellenbosch University, 2022-12) Moyo, Reuben Christopher; Nyasulu, Peter Suwilakwenda; Manda, Samuel; Govindasamy, Darshini; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Global Health. Epidemiology and Biostatistics.ENGLISH SUMMARY: Background: In sub-Saharan Africa, adolescent girls and young women (AGYW) have the highest risk of acquiring HIV. Risk factors for HIV in AGYM are well studied and known in the literature. However, there is need to combine these factors into a single summary measure that could be used in the identification of the AGYW who are more likely to acquire HIV and who may be linked to HIV Pre-Exposure Prophylaxis (PreP) which has shown to be effective in the prevention of new HIV infections among high-risk populations. This study aimed at developing and validating an HIV risk prediction tool for AGYW. Methods: We analyzed existing HIV-related data on 4,399 AGYW from South Africa. We used multivariable binary logistic regression to model coefficients for use in deriving risk scores. The HIV risk scores were computed from summing predictor coefficients of the resulting logistic regression model. The performance of the final model at discriminating between HIV infected and non-HIV infected AGYM was assessed using area under the receiver-operating curve (AUC) and measures of discriminative abilities such as predictive values, sensitivity, and specificity. The optimal cut-point of the risk score was determined using Youden index. Results: The weighted HIV prevalence among AGYW was 12.4% (11.7 – 14.0). Our risk scores ranged from -1.26 to 3.80 with a mean score of 1.38 and a standard deviation of 0.86. The optimal cut-point of the risk scores was 1.80 with sensitivity of 62% and specificity of 70%. The prediction model’s sensitivity was 15.19% and specificity of 98.92%. The model’s positive predictive value was 67.42% while the negative predictive value was 88.79%. Our model performed well at predicting HIV positivity with training AUC of 0.770 and a testing AUC of 0.751. Conclusion: Our risk score tool has shown good discrimination and calibration at predicting undiagnosed HIV in AGYW. This tool could provide a simple and low-cost strategy for screening AGYW in primary health care clinics or community settings. This risk assessment tool may also help service providers identify and link high-risk AGYW to HIV PreP services.