Browsing by Person "Vassall, Anna"
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Item Algorithm-guided empirical tuberculosis treatment for people with advanced HIV (TB Fast Track): An open-label, cluster-randomised trial(Elsevier, 2019-11-11) Grant, Alison D.; Charalambous, Salome; Tlali, Mpho; Karat, Aaron S.; Dorman, Susan E.; Hoffmann, Christopher J.; Johnson, Suzanne; Vassall, Anna; Churchyard, Gavin J.; Fielding, Katherine L.Background Tuberculosis, which is often undiagnosed, is the major cause of death among HIV-positive people. We aimed to test whether the use of a clinical algorithm enabling the initiation of empirical tuberculosis treatment by nurses in primary health-care clinics would reduce mortality compared with standard of care for adults with advanced HIV disease.Item Complexity and evidence in health sector decision-making: lessons from tuberculosis infection prevention in South Africa(Oxford University Press (OUP), 2022-07-29) Perera, Shehani; Parkhurst, Justin; Diaconu, Karin; Bozzani, Fiammetta; Vassall, Anna; Grant, Alison; Kielmann, KarinaAbstract To better understand and plan health systems featuring multiple levels and complex causal elements, there have been increasing attempts to incorporate tools arising from complexity science to inform decisions. The utilization of new planning approaches can have important implications for the types of evidence that inform health policymaking and the mechanisms through which they do so. This paper presents an empirical analysis of the application of one such tool—system dynamics modelling (SDM)—within a tuberculosis control programme in South Africa in order to explore how SDM was utilized, and to reflect on the implications for evidence-informed health policymaking. We observed group model building workshops that served to develop the SDM process and undertook 19 qualitative interviews with policymakers and practitioners who partook in these workshops. We analysed the relationship between the SDM process and the use of evidence for policymaking through four conceptual perspectives: (1) a rationalist knowledge-translation view that considers how previously-generated research can be taken up into policy; (2) a programmatic approach that considers existing goals and tasks of decision-makers, and how evidence might address them; (3) a social constructivist lens exploring how the process of using an evidentiary planning tool like SDM can shape the understanding of problems and their solutions; and (4) a normative perspective that recognizes that stakeholders may have different priorities, and thus considers which groups are included and represented in the process. Each perspective can provide useful insights into the SDM process and the political nature of evidence use. In particular, SDM can provide technical information to solve problems, potentially leave out other concerns and influence how problems are conceptualized by formalizing the boundaries of the policy problem and delineating particular solution sets. Undertaking the process further involves choices on stakeholder inclusion affecting whose interests may be served as evidence to inform decisions.Item Cost-effectiveness of tuberculosis infection prevention and control interventions in South African clinics: a model-based economic evaluation informed by complexity science methods(BMJ Publishing Group, 2023-02-15) Bozzani, Fiammetta Maria; McCreesh, Nicky; Diaconu, Karin; Govender, Indira; White, Richard G; Kielmann, Karina; Grant, Alison D; Vassall, AnnaIntroduction: Nosocomial Mycobacterium tuberculosis (Mtb) transmission substantially impacts health workers, patients and communities. Guidelines for tuberculosis infection prevention and control (TB IPC) exist but implementation in many settings remains suboptimal. Evidence is needed on cost-effective investments to prevent Mtb transmission that are feasible in routine clinic environments. Methods: A set of TB IPC interventions was codesigned with local stakeholders using system dynamics modelling techniques that addressed both core activities and enabling actions to support implementation. An economic evaluation of these interventions was conducted at two clinics in KwaZulu-Natal, employing agent-based models of Mtb transmission within the clinics and in their catchment populations. Intervention costs included the costs of the enablers (eg, strengthened supervision, community sensitisation) identified by stakeholders to ensure uptake and adherence. Results: All intervention scenarios modelled, inclusive of the relevant enablers, cost less than US$200 per disability-adjusted life-year (DALY) averted and were very cost-effective in comparison to South Africa’s opportunity cost-based threshold (US$3200 per DALY averted). Two interventions, building modifications to improve ventilation and maximising use of the existing Central Chronic Medicines Dispensing and Distribution system to reduce the number of clinic attendees, were found to be cost saving over the 10-year model time horizon. Incremental cost-effectiveness ratios were sensitive to assumptions on baseline clinic ventilation rates, the prevalence of infectious TB in clinic attendees and future HIV incidence but remained highly cost-effective under all uncertainty analysis scenarios. Conclusion: TB IPC interventions in clinics, including the enabling actions to ensure their feasibility, afford very good value for money and should be prioritised for implementation within the South African health system.Item Estimating waiting times, patient flow, and waiting room occupancy density as part of tuberculosis infection prevention and control research in South African primary health care clinics(Public Library of Science, 2022-07-20) Karat, Aaron S.; McCreesh, Nicky; Baisley, Kathy; Govender, Indira; Kallon, Idriss I.; Kielmann, Karina; MacGregor, Hayley; Vassall, Anna; Yates, Tom A.; Grant, Alison D.Transmission of respiratory pathogens, such as Mycobacterium tuberculosis and severe acute respiratory syndrome coronavirus 2, is more likely during close, prolonged contact and when sharing a poorly ventilated space. Reducing overcrowding of health facilities is a recognised infection prevention and control (IPC) strategy; reliable estimates of waiting times and ‘patient flow’ would help guide implementation. As part of the Umoya omuhle study, we aimed to estimate clinic visit duration, time spent indoors versus outdoors, and occupancy density of waiting rooms in clinics in KwaZulu-Natal (KZN) and Western Cape (WC), South Africa. We used unique barcodes to track attendees’ movements in 11 clinics, multiple imputation to estimate missing arrival and departure times, and mixed-effects linear regression to examine associations with visit duration. 2,903 attendees were included. Median visit duration was 2 hours 36 minutes (interquartile range [IQR] 01:36–3:43). Longer mean visit times were associated with being female (13.5 minutes longer than males; p<0.001) and attending with a baby (18.8 minutes longer than those without; p<0.01), and shorter mean times with later arrival (14.9 minutes shorter per hour after 0700; p<0.001). Overall, attendees spent more of their time indoors (median 95.6% [IQR 46–100]) than outdoors (2.5% [IQR 0–35]). Attendees at clinics with outdoor waiting areas spent a greater proportion (median 13.7% [IQR 1–75]) of their time outdoors. In two clinics in KZN (no appointment system), occupancy densities of ~2.0 persons/m2 were observed in smaller waiting rooms during busy periods. In one clinic in WC (appointment system, larger waiting areas), occupancy density did not exceed 1.0 persons/m2 despite higher overall attendance. In this study, longer waiting times were associated with early arrival, being female, and attending with a young child. Occupancy of waiting rooms varied substantially between rooms and over the clinic day. Light-touch estimation of occupancy density may help guide interventions to improve patient flow.Item How do participatory methods shape policy? Applying a realist approach to the formulation of a new tuberculosis policy in Georgia(2021-06-29) Marchal, Bruno; Abejirinde, Ibukun-Oluwa Omolade; Sulaberidze, Lela; Chikovani, Ivdity; Uchaneishvili, Maia; Shengelia, Natia; Diaconu, Karin; Vassall, Anna; Zoidze, Akaki; Giralt, Ariadna Nebot; Witter, SophieThis paper presents the iterative process of participatory multistakeholder engagement that informed the development of a new national tuberculosis (TB) policy in Georgia, and the lessons learnt. Guided by realist evaluation methods, a multistakeholder dialogue was organised to elicit stakeholders' assumptions on challenges and possible solutions for better TB control. Two participatory workshops were conducted with key actors, interspersed by reflection meetings within the research team and discussions with policymakers. Using concept mapping and causal mapping techniques, and drawing causal loop diagrams, we visualised how actors understood TB service provision challenges and the potential means by which a results-based financing (RBF) policy could address these. The study was conducted in Tbilisi, Georgia. A total of 64 key actors from the Ministry of Labour, Health and Social Affairs, staff of the Global Fund to Fight AIDS, TB and Malaria Georgia Project, the National Centre for Disease Control and Public Health, the National TB programme, TB service providers and members of the research team were involved in the workshops. Findings showed that beyond provider incentives, additional policy components were necessary. These included broadening the incentive package to include institutional and organisational incentives, retraining service providers, clear redistribution of roles to support an integrated care model, and refinement of monitoring tools. Health system elements, such as effective referral systems and health information systems were highlighted as necessary for service improvement. Developing policies that address complex issues requires methods that facilitate linkages between multiple stakeholders and between theory and practice. Such participatory approaches can be informed by realist evaluation principles and visually facilitated by causal loop diagrams. This approach allowed us leverage stakeholders' knowledge and expertise on TB service delivery and RBF to codesign a new policy. [Abstract copyright: © Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.]Item Qualitative system dynamics modelling to support the design and implementation of tuberculosis infection prevention and control measures in South African primary health care facilities(Oxford University Press (OUP), 2024-08-31) Diaconu, Karin; Karat, Aaron; Bozzani, Fiametta; McCreesh, Nicky; Falconer, Jennifer; Voce, Anna; Vassall, Anna; Grant, Alison D; Kielmann, KarinaTuberculosis infection prevention and control (TB IPC) measures are a cornerstone of policy, but measures are diverse and variably implemented. Limited attention has been paid to the health system environment which influences successful implementation of these measures. We used qualitative system dynamics and group-model-building methods 1) develop a qualitative causal map of the interlinked drivers of Mycobacterium tuberculosis (Mtb) transmission in South African primary health care facilities which in turn, helped us to 2) identify plausible IPC interventions to reduce risk of transmission. Two one-day participatory workshops were held in 2019 with policy- and decision-makers at national and provincial level, and patient advocates and health professionals at clinic and district level. Causal loop diagrams were generated by participants and combined by investigators. The research team reviewed diagrams to identify the drivers of nosocomial transmission of Mtb in primary health care facilities. Interventions proposed by participants were mapped onto diagrams to identify anticipated mechanisms of action and effect. Three systemic drivers were identified: 1) Mtb nosocomial transmission is driven by bottlenecks in patient flow at given times; 2) IPC implementation and clinic processes are anchored within a staff “culture of nominal compliance”; and 3) limited systems-learning at policy level inhibits effective clinic management and IPC implementation. Interventions prioritised by workshop participants included infrastructural, organisational, and behavioural strategies that target three areas: 1) improve air quality; 2) improve use of personal protective equipment; and 3) reduce the number of individuals in the clinic. In addition to core mechanisms, participants elaborated specific additional enablers that would help sustain implementation. Qualitative system dynamics modelling (SDM) methods allowed us to capture stakeholder views and potential solutions to address the problem of sub-optimal TB IPC implementation. The participatory elements of SDM facilitated problem-solving and inclusion of multiple factors frequently neglected when considering implementation.Item Tuberculosis infection prevention and control: Why we need a whole systems approach(BMC, 2020-05-25) Kielmann, Karina; Karat, Aaron S.; Zwama, Gimenne; Colvin, Christopher; Swartz, Alison; Voce, Anna S.; Yates, Tom A.; MacGregor, Hayley; McCreesh, Nicky; Kallon, Idriss; Vassall, Anna; Govender, Indira; Seeley, Janet; Grant, Alison D.Infection prevention and control (IPC) measures to reduce transmission of drug-resistant and drug-sensitive tuberculosis (TB) in health facilities are well described but poorly implemented. The implementation of TB IPC has been assessed primarily through quantitative and structured approaches that treat administrative, environmental, and personal protective measures as discrete entities. We present an on-going project entitled Umoya omuhle (“good air”), conducted in two provinces of South Africa, that adopts an interdisciplinary, ‘whole systems’ approach to problem analysis and intervention development for reducing nosocomial transmission of Mycobacterium tuberculosis (Mtb) through improved IPC. We suggest that TB IPC represents a complex intervention that is delivered within a dynamic context shaped by policy guidelines, health facility space, infrastructure, organisation of care, and management culture. Methods drawn from epidemiology, anthropology, and health policy and systems research enable rich contextual analysis of how nosocomial Mtb transmission occurs, as well as opportunities to address the problem holistically. A ‘whole systems’ approach can identify leverage points within the health facility infrastructure and organisation of care that can inform the design of interventions to reduce the risk of nosocomial Mtb transmission.Item Using system dynamics modelling to estimate the costs of relaxing health system constraints: A case study of tuberculosis prevention and control interventions in South Africa(Oxford University Press, 2022-01-13) Bozzani, Fiammetta M.; Diaconu, Karin; Gomez, Gabriela B.; Karat, Aaron S.; Kielmann, Karina; Grant, Alison D.; Vassall, AnnaHealth system constraints are increasingly recognised as an important addition to model-based analyses of disease control interventions, as they affect achievable impact and scale. Enabling activities implemented alongside interventions to relax constraints and reach the intended coverage may incur additional costs, which should be considered in priority setting decisions. We explore the use of group model building, a participatory system dynamics modelling technique, for eliciting information from key stakeholders on the constraints that apply to tuberculosis infection prevention and control processes within primary healthcare clinics in South Africa. This information was used to design feasible interventions, including the necessary enablers to relax existing constraints. Intervention and enabler costs were then calculated at two clinics in KwaZulu-Natal using input prices and quantities from the published literature and local suppliers. Among the proposed interventions, the most inexpensive were retrofitting buildings to improve ventilation (US$ 1,644 per year), followed by maximising the use of community sites for medication collection among stable patients on antiretroviral therapy (US$ 3,753) and introducing appointments systems to reduce crowding (US$ 9,302). Enablers identified included enhanced staff training, supervision and patient engagement activities to support behaviour change and local ownership. Several of the enablers identified by the stakeholders, such as obtaining building permissions or improving information flows between levels of the health systems, were not amenable to costing. Despite this limitation, an approach to costing rooted in system dynamics modelling can be successfully applied in economic evaluations to more accurately estimate the ‘real world’ opportunity cost of intervention options. Further empirical research applying this approach to different intervention types (e.g. new preventive technologies or diagnostics) may identify interventions that are not cost-effective in specific contexts based on the size of the required investment in enablers.