Browsing by Author "Siegfried, Nandi"

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    African HIV/AIDS trials are more likely to report adequate allocation concealment and random generation than North American trials
    (Public Library of Science (PLOS), 2008-10) Siegfried, Nandi; Clarke, Michael; Volmink, Jimmy; Van der Merwe, Lize
    Background: Adherence to good methodological quality is necessary to minimise bias in randomised conrolled trials (RCTs). Specific trial characteristics are associated with better trial quality, but no studies to date are specific to HIV/AIDS or African trials. We postulated that location may negatively impact on trial quality in regions where resources are scarce. Methods: 1) To compare the methodological quality of all HIV/AIDS RCTs conducted in Africa with a random sample of similar trials conducted in North America; 2) To assess whether location is predictive of trial quality. We searched MEDLINE, EMBASE, CENTRAL and LILACS. Eligible trials were 1) randomized, 2) evaluations of preventive or treatment interventions for HIV/AIDS, 3) reported before 2004, and 4) conducted wholly or partly (if multi-centred) in Africa or North America. We assessed adequacy of random generation, allocation concealment and masking of assessors. Using univariate and multivariate logistic regression analyses we evaluated the association between location (Africa versus North America) and these domains. Findings: The African search yielded 12,815 records, from which 80 trials were identified. The North American search yielded 13,158 records from which 785 trials were identified and a random sample of 114 selected for analysis. African trials were three times more likely than North American trials to report adequate allocation concealment (OR = 3.24; 95%CI: 1.59 to 6.59; p<0.01) and twice as likely to report adequate generation of the sequence (OR = 2.36; 95%CI: 1.20 to 4.67; p = 0.01), after adjusting for other confounding factors. Additional significant factors positively associated with quality were an a priori sample size power calculation, restricted randomization and inclusion of a flow diagram detailing attrition. We did not detect an association between location and outcome assessor masking. Conclusions: The higher quality of reporting of methodology in African trials is noteworthy. Most African trials are externally funded, and it is possible that stricter agency requirements when leading trials in other countries and greater experience and training of principal investigators of an international stature, may account for this difference. © 2008 Siegfried et al.
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    Concept and development of an interactive tool for trial recruitment planning and management
    (BMC (part of Springer Nature), 2021-03-06) Spies, Ruan Arnold; Siegfried, Nandi; Myers, Bronwyn; Grobbelaar, Sara S.
    Background: Predicting and monitoring recruitment in large, complex trials is essential to ensure appropriate resource management and budgeting. In a novel partnership between clinical trial investigators of the South African Medical Research Council and industrial engineers from the Stellenbosch University Health Systems Engineering and Innovation Hub, we developed a trial recruitment tool (TRT). The objective of the tool is to serve as a computerised decisions-support system to aid the planning and management phases of the trial recruitment process. Method: The specific requirements of the TRT were determined in several workshops between the partners. A Poisson process simulation model was formulated and incorporated in the TRT to predict the recruitment duration. The assumptions underlying the model were made in consultation with the trial team at the start of the project and were deemed reasonable. Real-world data extracted from a current cluster trial, Project MIND, based in 24 sites in South Africa was used to verify the simulation model and to develop the monitoring component of the TRT. Results: The TRT comprises a planning and monitoring component. The planning component generates different trial scenarios for predicted trial recruitment duration based on user inputs, e.g. number of sites, initiation delays. The monitoring component uses and analyses the data retrieved from the trial management information system to generate different levels of information, displayed visually on an interactive, user-friendly dashboard. Users can analyse the results at trial or site level, changing input parameters to see the resultant effect on the duration of trial recruitment. Conclusion: This TRT is an easy-to-use tool that assists in the management of the trial recruitment process. The TRT has potential to expedite improved management of clinical trials by providing the appropriate information needed for the planning and monitoring of the trial recruitment phase. This TRT extends prior tools describing historic recruitment only to using historic data to predict future recruitment. The broader project demonstrates the value of collaboration between clinicians and engineers to optimise their respective skillsets.
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    Priority areas for cannabis and cannabinoid product research in South Africa
    (AOSIS, 2018-06) Augustine, Tanya N.; Cairns, Carel J.; Chetty, Sean; Dannatt, Lisa G.; Gravett, Nadine; Grey, Glenda; Grobler, Gerhard; Jafta, Zukiswa; Kamerman, Peter; Lopes, John; Matsabisa, Motlalepula G.; Mugabo, Pierre; Mulder, Michelle; Parry, Charles; Rataemane, Solomon; Siegfried, Nandi; Steenkamp, Vanessa; Thomas, Eileen; Van Zyl-Smit, Richard
    The legalisation of cannabis for medicinal use is a contentious space both politically and in the medical community. In 2014, the Medical Innovation Bill introduced by Mario Oriani-Ambrosini MP, aimed to shift the political and legal positions of cannabis as an illegal substance to one available for research and medical use. To date, progress on this has been slow. Cannabis and cannabinoid products are currently available for medicinal use in several countries, including the Netherlands and 29 states in the United States. Locally, anecdotal reports suggest that many of our patients with chronic medical conditions are using cannabis and cannabis-derived or cannabinoid products for symptom alleviation.