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1. Improving uptake and completion of pulmonary rehabilitation in COPD with lay health workers: feasibility of a clinical trial

Author

White P, Gilworth G, Lewin S, Hogg L, Tuffnell R, Taylor SJC, Hopkinson NS, Hart N, Singh SJ, and Wright AJ

Subjects
Pulmonary rehabilitation, Chronic Obstructive Pulmonary Disease (COPD), lay health workers, intervention fidelity, Diseases of the respiratory system, RC705-779
Abstract

Patrick White,1 Gill Gilworth,1 Simon Lewin,2,3 Lauren Hogg,4 Rachel Tuffnell,5 Stephanie JC Taylor,6 Nicholas S Hopkinson,7 Nicholas Hart,8 Sally J Singh,9 Alison J Wright10 1Department of Public Health and Primary Care, School of Population Health and Environmental Sciences, King’s College London, London, UK; 2Norwegian Institute of Public Health, Oslo, Norway; 3Health Systems Research Unit, South African Medical Research Council, Cape Town, South Africa; 4Physiotherapy Department, Guy’s and St Thomas’ NHS Foundation Trust, London, UK; 5The Pulmonary Rehabilitation and Integrated Respiratory Team, King’s College Hospital NHS Foundation Trust, London, UK; 6Centre for Primary Care and Public Health, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK; 7National Heart and Lung Institute, Imperial College London, London, UK; 8Lane Fox Respiratory Service, Guy’s and St Thomas’ NHS Foundation Trust, London, UK; 9Centre for Exercise and Rehabilitation Science, University Hospitals of Leicester NHS Trust, Leicester, UK; 10Department of Clinical, Educational and Health Psychology, University College London, London, UK Purpose: This study was designed to evaluate the feasibility of a cluster randomized controlled trial to test the efficacy of lay health workers (LHWs) in improving the uptake and completion of pulmonary rehabilitation (PR) in the treatment of COPD.Materials and methods: LHWs, trained in confidentiality, role boundaries, and behavior change techniques, supported patients newly referred for PR. Interactions between LHWs and participants were recorded with smartphones. Outcomes were recruitment and retention rates of LHWs, questionnaire and interview-evaluated acceptability and analysis of intervention fidelity.Results: Forty (36%) of 110 PR-experienced COPD patients applied to become LHWs. Twenty (18%) were selected for training. Twelve (11%) supported patients. Sixty-six COPD patients referred for PR received the intervention (5.5 participants per LHW). Ten LHWs were retained to the end of the study. Seventy-three percent of supported patients were satisfied or very satisfied with the intervention. LHWs delivered the intervention with appropriate style and variable fidelity. LHWs would welcome more intensive training. Based on this proof of concept, a cluster randomized controlled trial of an LHW intervention to improve uptake and completion of PR is feasible.Conclusion: PR-experienced COPD patients can be recruited, trained, and retained as LHWs to support participation in PR, and can deliver the intervention. Participant COPD patients found the intervention acceptable. A cluster randomized controlled clinical trial is feasible. Keywords: uptake, completion, recruitment, retention, intervention fidelity

Published
2019

2. Building capacity for antiretroviral delivery in South Africa: A qualitative evaluation of the PALSA PLUS nurse training programme

Author

English R, Mayers P, Fairall L, Lewin S, Stein J, Bheekie A, Bateman E, and Zwarenstein M

Subjects
Public aspects of medicine, RA1-1270
Abstract

Abstract Background South Africa recently launched a national antiretroviral treatment programme. This has created an urgent need for nurse-training in antiretroviral treatment (ART) delivery. The PALSA PLUS programme provides guidelines and training for primary health care (PHC) nurses in the management of adult lung diseases and HIV/AIDS, including ART. A process evaluation was undertaken to document the training, explore perceptions regarding the value of the training, and compare the PALSA PLUS training approach (used at intervention sites) with the provincial training model. The evaluation was conducted alongside a randomized controlled trial measuring the effects of the PALSA PLUS nurse-training (Trial reference number ISRCTN24820584). Methods Qualitative methods were utilized, including participant observation of training sessions, focus group discussions and interviews. Data were analyzed thematically. Results Nurse uptake of PALSA PLUS training, with regard not only to ART specific components but also lung health, was high. The ongoing on-site training of all PHC nurses, as opposed to the once-off centralized training provided for ART nurses only at non-intervention clinics, enhanced nurses' experience of support for their work by allowing, not only for ongoing experiential learning, supervision and emotional support, but also for the ongoing managerial review of all those infrastructural and system-level changes required to facilitate health provider behaviour change and guideline implementation. The training of all PHC nurses in PALSA PLUS guideline use, as opposed to ART nurses only, was also perceived to better facilitate the integration of AIDS care within the clinic context. Conclusion PALSA PLUS training successfully engaged all PHC nurses in a comprehensive approach to a range of illnesses affecting both HIV positive and negative patients. PHC nurse-training for integrated systems-based interventions should be prioritized on the ART funding agenda. Training for individual provider behaviour change is nonetheless only one aspect of the ongoing system-wide interventions required to effect lasting improvements in patient care in the context of an over-burdened and under-resourced PHC system.

Published
2008
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3. Evolution of charge order topology across a magnetic phase transition in cuprate superconductors

Author

Kang, M, Pelliciari, J, Frano, A, Breznay, N, Schierle, E, Weschke, E, Sutarto, R, He, F, Shafer, P, Arenholz, E, Chen, M, Zhang, K, Ruiz, A, Hao, Z, Lewin, S, Analytis, J, Krockenberger, Y, Yamamoto, H, Das, T, and Comin, R

Subjects
cond-mat.str-el, Mathematical Sciences, Physical Sciences, Fluids & Plasmas
Abstract

Charge order is now accepted as an integral constituent of cuprate high-temperature superconductors, one that is intimately related to other electronic instabilities including antiferromagnetism and superconductivity1–11. Unlike conventional Peierls density waves, the charge correlations in cuprates have been predicted to display a rich momentum space topology depending on the underlying fermiology12–18. However, charge order has only been observed along the high-symmetry Cu–O bond directions. Here, using resonant soft X-ray scattering, we investigate the evolution of the full momentum space topology of charge correlations in T′-(Nd,Pr)2CuO4 as a function of electron doping. We report that, when the parent Mott insulator is doped, charge correlations first emerge with full rotational symmetry in momentum space, indicating glassy charge density modulation in real space possibly seeded by local defects. At higher doping levels, the orientation of charge correlations is locked to the Cu–O bond directions, restoring a more conventional long-ranged bidirectional charge order. Through charge susceptibility calculations, we reproduce the evolution in topology of charge correlations across the antiferromagnetic phase boundary and propose a revised phase diagram of T′-Ln2CuO4 with a superconducting region extending toward the Mott limit.

Published
2019

5. Estimated GFR and the Effect of Intensive Blood Pressure Lowering After Acute Intracerebral Hemorrhage

Author

Anderson, C.S., Chalmers, J., Arima, H., Davis, S., Heeley, E., Huang, Y., Lavados, P., Neal, B., Parsons, M.W., Lindley, R., Morgenstern, L., Robinson, T., Stapf, C., Tzourio, C., Wang, J.G., Chen, S., Chen, X.Y., Cui, L., Liu, Z., Lu, C., Wang, J., Wu, S., Xu, E., Yang, Q., Zhang, C., Zhang, J., Beer, R., Schmutzhard, E., Redondo, P., Kaste, M., Soinne, L., Tatlisumak, T., Wartenberg, K., Ricci, S., Klijn, K., Azevedo, E., Chamorro, A., Arnold, M., Fischer, U., Kaul, S., Pandian, J., Boyini, H., Singh, S., Rabinstein, A.A., Estol, C., Silva, G., Olavarria, V.V., Robinson, T.G., Simes, R.J., Bousser, M.-G., Hankey, G., Jamrozik, K., Johnston, S.C., Li, S., Bailey, K., Cheung, T., Delcourt, C., Chintapatla, S., Ducasse, E., Erho, T., Hata, J., Holder, B., Knight, E., Leroux, M., Sassé, T., Odgers, E., Walsh, R., Wolfowicz, Z., Chen, G., Fuentes, S., Peng, B., Schneble, H.-M., Wang, M.-X., Billot, L., Heritier, S., Li, Q., Woodward, M., Abimbola, S., Anderson, S., Chan, E., Cheng, G., Chmielnik, P., Leighton, S., Liu, J.-Y., Rasmussen, B., Saxena, A., Tripathy, S., Armenis, M., Baig, M.A., Naidu, B., Starzec, G., Steley, S., Moles, A., Ruiz, A., Zimmermann, M., Marinho, J., Alves, S., Angelim, R., Araujo, J., Kawakami, L., Bustos, C., Gonzalez, F., Munoz Venturelli, P., Chen, X., Jia, R., Li, N., Qu, S., Shu, Y., Song, A., Sun, J., Xiao, J., Zhao, Y., Huang, Q., Vicaut, E., Chamam, A., Viaud, M.-C., Dert, C., Fiedler, U., Jovis, V., Kabla, S., Marchand, S., Pena, A., Rochaud, V., Mallikarjuna, K., Hasan, N., Berge, E., Sandset, E.C., Forårsveen, A.S., Richardson, D., Kumar, T., Lewin, S., Poulter, N., Field, J., Anjum, A., Wilson, A., Perelmuter, H., Agarie, A.M., Barboza, A.G., Recchia, L.A., Miranda, I.F., Rauek, S.G., Duplessis, R.J., Dewey, H., Walker, L., Petrolo, S., Bladin, C., Sturm, J., Crimmins, D., Griffiths, D., Schutz, A., Zenteno, V., Miteff, F., Spratt, N., Kerr, E., Levi, C.R., Phan, T.G., Ma, H., Sanders, L., Moran, C., Wong, K., Read, S., Henderson, R., Wong, A., Hull, R., Skinner, G., Hand, P., Yan, B., Tu, H., Campbell, B., Blacker, D.J., Wijeratne, T., Pathirage, M., Jasinararchchi, M., Matkovic, Z., Celestino, S., Gruber, F., Vosko, M.R., Diabl, E., Rathmaier, S., Pfausler, B., Helbok, R., Fazekas, F., Fischer, R., Poltrum, B., Zechner, B., Trummer, U., Rutgers, M.P., Peeters, A., Dusart, A., Duray, M.-C., Parmentier, C., Ferrao-Santos, S., Brouns, R., De Raedt, S., De Smedt, A., VanHooff, R.-J., De Keyser, J., Martins, S.C.O., de Almeida, A.G., Broudani, R., Titton, N.F., de Freitas, G.R., Cardoso, F.M., Giesel, L.M., Lima, N.A., Jr, Ferraz de Almeida, A.C., Gomes, R.B., Borges dos Santos, T.S., Veloso Soares, E.M., Neto, O.L.A., Silva, G.S., Gomes, D.L., de Carvalho, F.A., Miranda, M., Marques, A., Zétola, V.F., de Matia, G., Lange, M.C., Montes, J., Reccius, A., Soto, A., Rivas, R., Klapp, C., Illanes, S., Aguilera, C., Castro, A., Figueroa, C., Benavides, J., Salamanca, P., Concha, M.C., Pajarito, J., Araya, P., Guerra, F., Li, Y., Liu, G., Wang, B., Chong, Y., He, M., Wang, L., Liu, J., Zhang, X., Lai, C., Jiang, H., Cui, S., Tao, Q., Zhang, Y., Yao, S., Xu, M., Xiao, H., Hu, J., Tang, J., Ji, H., Jiang, M., Yu, F., Yang, X., Guo, X., Wang, Y., Wu, L., Gao, Y., Sun, D., Huang, X., Liu, L., Li, P., Jiang, Y., Li, H., Lu, H., Zhou, J., Yuan, C., Qi, X., Qiu, F., Qian, H., Wang, W., Sun, W., Li, F., Liu, R., Peng, Q., Ren, Z., Fan, C., Wang, H., Wang, T., Shi, F., Duan, C., Chen, Z., Tan, X., Zhao, Z., Chen, J., Han, T., Zhang, L., Hu, Q., Hou, Q., Zhao, X., Zeng, G., Ma, L., Wang, F., Zeng, L., Guo, Z., Fu, Y., Song, Y., Tai, L., Liu, X., Su, X., Yang, Y., Dong, R., Xu, Y., Tian, S., Cheng, S., Su, L., Xie, X., Xu, T., Geng, D., Yan, X., Fan, H., Zhao, N., Wang, S., Yang, J., Yan, M., Li, L., Li, Z., Xu, X., Lian, Y., Sun, H., Liu, D., Wang, N., Tang, Q., Han, Z., Feng, L., Cui, Y., Tian, J., Chang, H., Sun, X., Liu, C., Wen, Z., Lin, Q., Sun, L., Hu, B., Zou, M., Bao, Q., Lin, X., Zhao, L., Tian, X., Wang, X., Li, X., Hao, L., Duan, Y., Wang, R., Wei, Z., Ren, S., Ren, H., Dong, Y., Cheng, Y., Liu, W., Han, J., Zhang, Z., Zhu, J., Qian, J., Sun, Y., Liu, K., Long, F., Peng, X., Zhang, Q., Yuan, Z., Wang, C., Huang, M., He, P., You, Y., Xia, J., Zhou, L., Hou, Y., Qi, Y., Mei, L., Lu, R., Ping, L., Zhou, S., Zhang, S., Zou, R., Guo, J., Li, M., Wei, W., Curtze, S., Saarela, M., Strbian, D., Scheperjans, F., De Broucker, T., Henry, C., Cumurciuc, R., Ibos-Augé, N., Zéghoudi, A.-C., Pico, F., Dereeper, O., Simian, M.-C., Boisselier, C., Mahfoud, A., Timsit, S., Merrien, F.M., Guillon, B., Sevin, M., Herisson, F., Magne, C., Ameri, A., Cret, C., Stefanizzi, S., Klapzcynski, F., Denier, C., Sarov-Riviere, M., Reiner, P., Mawet, J., Hervé, D., Buffon, F., Touzé, E., Domigo, V., Lamy, C., Calvet, D., Pasquini, M., Alamowitch, S., Favrole, P., Muresan, I.-P., Crozier, S., Rosso, C., Pires, C., Leger, A., Deltour, S., Cordonnier, C., Henon, H., Rossi, C., Zuber, M., Bruandet, M., Tamazyan, R., Join-Lambert, C., Juettler, E., Krause, T., Maul, S., Endres, M., Jungehulsing, G.J., Hennerici, M., Griebe, M., Sauer, T., Knoll, K., Huber, R., Knauer, K., Knauer, C., Raubold, S., Schneider, H., Hentschel, H., Lautenschläger, C., Schimmel, E., Dzialowski, I., Foerch, C., Lorenz, M., Singer, O., Meyer dos Santos, I.M.R., Hartmann, A., Hamann, A., Schacht, A., Schrader, B., Teíchmann, A., Wartenberg, K.E., Mueller, T.J., Jander, S., Gliem, M., Boettcher, C., Rosenkranz, M., Beck, C., Otto, D., Thomalla, G., Cheng, B., Wong, K.S., Leung, T.W., Soo, Y.O.Y., Prabhakar, S., Kesavarapu, S.R., Gajjela, P.K., Chenna, R.R., Ummer, K., Basheer, M., Andipet, A., Jagarlapudi, M.K.M., Mohammed, A.U.R., Pawar, V.G., Eranki, S.S.K., Singh, Y., Akhtar, N., Borah, N.C., Ghose, M., Choudhury, N., Ichaporia, N.R., Shendge, J., Khese, S., Pamidimukkala, V., Inbamuthaiah, P., Nuthakki, S.R., Tagallamudi, N.M.R., Gutti, A.K., Khurana, D., Kesavarapu, P., Jogi, V., Garg, A., Samanta, D., Sarma, G.R.K., Nadig, R., Mathew, T., Anandan, M.A., Caterbi, E., Zini, A., Cavazzuti, M., Casoni, F., Pentore, R., Falzone, F., Mazzoli, T., Greco, L.M., Menichetti, C., Coppola, F., Cenciarelli, S., Gallinella, E., Mattioni, A., Condurso, R., Sicilia, I., Zampolini, M., Corea, F., Barbi, M., Proietti, C., Toni, D., Pieroni, A., Anzini, A., Falcou, A., Demichele, M., Klijn, C.J.M., Tveiten, A., Thortveit, E.T., Pettersen, S., Holand, N., Hitland, B., Johnsen, S.H., Eltoft, A., Wasay, M., Kamal, A., Iqrar, A., Ali, L., Begum, D., Gama, G., Fonseca, L., Moreira, G., Veloso, L.M., Pinheiro, D., Paredes, L., Rozeira, C., Gregorio, T., Segura Martin, T., Ayo, O., Garcia-Garcia, J., Feria Vilar, I., Gómez Fernández, I., Amaro, S., Urra, X., Obach, V., Cervera, A., Silva, Y., Serena, J., Castellanos, M., Terceno, M., Van Eendenburg, C., Weck, A., Findling, O., Lüdi, R., Warburton, E.A., Day, D., Butler, N., Bumanlag, E., Caine, S., Steele, A., Osborn, M., Dodd, E., Murphy, P., Esisi, B., Brown, E., Hayman, R., Baliga, V.K.V., Minphone, M., Kennedy, J., Reckless, I., Pope, G., Teal, R., Michael, K., Manawadu, D., Kalra, L., Lewis, R., Mistry, B., Cattermole, E., Hassan, A., Mandizvidza, L., Bamford, J., Brooks, H., Bedford, C., Whiting, R., Baines, P., Hussain, M., Harvey, M., Fotherby, K., McBride, S., Bourke, P., Morgan, D., Jennings-Preece, K., Price, C., Huntley, S., Riddell, V.E., Storey, G., Lakey, R.L., Subramanian, G., Jenkinson, D., Kwan, J., David, O., Tiwari, D., James, M., Keenan, S., Eastwood, H., Shaw, L., Kaye, P., Button, D., Madigan, B., Williamson, D., Dixit, A., Davis, J., Hossain, M.O., Ford, G.A., Parry-Jones, A., O'Loughlin, V., Jarapa, R., Naing, Z., Lovelock, C., O'Reilly, J., Khan, U., Bhalla, A., Rudd, A., Birns, J., Werring, D.J., Law, R., Perry, R., Jones, I., Erande, R., Roffe, C., Natarajan, I., Ahmad, N., Finney, K., Lucas, J., Mistri, A., Eveson, D., Marsh, R., Haunton, V., Fugate, J.E., Lepore, S.W., Zheng, Danni, Sato, Shoichiro, Arima, Hisatomi, Heeley, Emma, Delcourt, Candice, Cao, Yongjun, Chalmers, John, and Anderson, Craig S.

Published
2016
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6. Dramatic rise in plasma viremia after CD8(+) T cell depletion in simian immunodeficiency virus-infected macaques.

Author

Jin, X, Bauer, DE, Tuttleton, SE, Lewin, S, Gettie, A, Blanchard, J, Irwin, CE, Safrit, JT, Mittler, J, Weinberger, L, Kostrikis, LG, Zhang, L, Perelson, AS, and Ho, DD

Subjects
CD4-Positive T-Lymphocytes, CD8-Positive T-Lymphocytes, Animals, Macaca mulatta, Viremia, Simian Acquired Immunodeficiency Syndrome, Virus Replication, Simian immunodeficiency virus, Simian Immunodeficiency Virus, simian immunodeficiency virus, macaque, OKT8, viremia, cytotoxic T lymphocyte, Medical and Health Sciences, Immunology
Abstract

To determine the role of CD8(+) T cells in controlling simian immunodeficiency virus (SIV) replication in vivo, we examined the effect of depleting this cell population using an anti-CD8 monoclonal antibody, OKT8F. There was on average a 99.9% reduction of CD8 cells in peripheral blood in six infected Macaca mulatta treated with OKT8F. The apparent CD8 depletion started 1 h after antibody administration, and low CD8 levels were maintained until day 8. An increase in plasma viremia of one to three orders of magnitude was observed in five of the six macaques. The injection of a control antibody to an infected macaque did not induce a sustained viral load increase, nor did it significantly reduce the number of CD8(+) T cells. These results demonstrate that CD8 cells play a crucial role in suppressing SIV replication in vivo.

Published
1999

10. The passenger hypothesis: HIV exploits CD4 T-cell homeostasis to promote long-term persistence of its reservoirs

Author

Reeves, D., Bacchus-Souffan, C., Fitch, M., Symons, J., Abdel-Mohsen, M., Hoh, R., Ahn, H., Deeks, S., Lewin, S., Hellerstein, M., McCune, J.M., Hunt, P., and Schiffer, J.

Subjects
Antiviral agents -- Patient outcomes, CD4 lymphocytes -- Health aspects, Cell differentiation -- Health aspects, Host-virus relationships, HIV infection -- Development and progression -- Drug therapy, Health
Abstract

Background: The reservoir of latently infected CD4+ T cells ensures HIV persistence during suppressive antiretroviral therapy (ART). The proliferation of reservoir cells carries provirus along as a passenger and produces [...]

Published
2021
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11. Use of the Informed Health Choices digital resources for teaching lower secondary school students in Rwanda to think critically about health: protocol for a process evaluation

Author

Mugisha, M, Nyirazinyoye, L, Oxman, AD, Simbi, CMC, Chesire, F, Ssenyonga, R, Oxman, M, Nsangi, A, Semakula, D, Dahlgren, A, Kaseje, M, Sewankambo, NK, Rosenbaum, S, and Lewin, S

Subjects
critical thinking, process evaluation, adolescents, treatment claims, health literacy, Rwanda
Abstract

Background: The Informed Health Choices (IHC) network is a group of researchers aiming to develop the public’s critical thinking skills and help them make informed health choices. We started with young people and developed the primary and secondary school resources for teaching critical thinking about health choices. The “Be Smart about your Health” secondary school resources are designed for lower secondary students and will be evaluated in randomized trials in three countries: Kenya, Rwanda, and Uganda. This protocol is for a process evaluation that will be conducted alongside the trial in Rwanda. The aim is to assess the implementation process, impacts of the intervention, and factors affecting the impacts and scaling up use of the resources. Methods: We will follow the UK Medical Research Council’s guidance for designing process evaluations of complex interventions alongside randomized trials. We will use quantitative and qualitative methods. We will collect quantitative data to assess lessons taught (dose), students’ attendance (reach) and any alterations in how the intervention (adaptation) is delivered in all schools allocated to the intervention arm (n=42). We will explore the intended and unintended effects, and transfer of learning through focus group discussions (FGDs) with students (n=8-10 FGDs), their parents/guardians (n=5 FGDs) and their teachers using key informant interviews (KIIs) (n=8-10 KIIs). We will also explore factors affecting the effective delivery and scaling up of the intervention through interviews with teachers (n=8-10 KIIs), school administrators (n=8-10 KIIs), district authorities (n=5 KII) and policymakers in education (n=5 KIIs). We will collect qualitative data in about 8-10 schools varying by district, school ownership, and school performance. We will analyse quantitative data using descriptive statics and qualitative data using thematic content analysis and framework analysis.

Published
2022
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15. EPOC Qualitative Evidence Syntheses: Protocol and review template v1.3

Author

Glenton C, Bohren MA, Downe S, Paulsen EJ, Lewin S, on behalf of Effective Practice and Organisation of Care (EPOC).

Subjects
Cochrane EPOC, systematic review, qualitative evidence synthesis, education, qualitative research
Abstract

EPOC Qualitative Evidence Syntheses: Protocol and review template Version 1.3 21 January 2022 Cochrane Effective Practice and Organisation of Care (EPOC), https://epoc.cochrane.org

Published
2022
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16. Adults' views and experiences of vaccines developed in response to the COVID-19 pandemic: a qualitative evidence synthesis

Author

Maria, ARJ, Cooper, S, Glenton, C, Lewin, S, Meskell, P, Suleman, M, and Shepperd, S

Subjects
Pharmacology (medical)
Abstract

This is a protocol for a Cochrane Review (qualitative). The objectives are as follows: Objectives The objective of this review is to identify, appraise and synthesise qualitative studies that explored adults’ views and experiences towards vaccination in the context of the COVID‐19 pandemic. A secondary objective is to compare this evidence with qualitative evidence that explores people’s perspectives of vaccines developed in response to Ebola, Hong Kong flu and Swine flu.

Published
2022

17. Soils, Science and Community ActioN (SoilSCAN): a citizen science tool to empower community-led land management change in East Africa

Author

Kelly, C., Wynants, M., Wynants, Maarten, Patrick, A., Taylor, A., Mkilema, F., Nasseri, M., Lewin, S., Munishi, L., Mtei, K., Ndakidemi, P., and Blake, W.

Subjects
Environmental Sciences related to Agriculture and Land-use
Abstract

Pastoralist communities worldwide face complex challenges regarding food and feed productivity. Primary production systems are under stress, nutritional choices are changing and the relationship between development and agriculture is undergoing profound transformation. Under increasing pressure from climate and land use change, East African agro-pastoral systems are approaching a tipping point in terms of land degradation. There is an urgent need for evidence-led sustainable land management interventions to reverse degradation of natural resources that support food and water security. A key barrier, however, is a lack of high spatial resolution soil health data wherein collecting such information for each individual community is beyond their means. In this context, we tested whether bridging such data gaps could be achieved through a coordinated programme at the boundary between participation and citizen science. Key outputs included a community-led trial of a hand-held soil scanner, which highlighted a range of positive benefits and practical challenges in using this technology in this context, with identification of some potential solutions; and a targeted soil organic matter and nutrient status dataset in a small catchment-based community setting. The results show that if the practical challenges can be resolved, use of portable soil scanner technology has the potential to fill key knowledge gaps and thereby improve resilience to the threat of land degradation through locally responsive farmer and community decision-making.

Published
2022

19. Subsequent full publication of qualitative studies presented at United Kingdom Royal College of Nursing Research Conference 2015 and 2016 : a follow‐up study

Author

Toews, I., Nyirenda, J.L.Z., Stadelmaier, J., Schwarzer, G., Noyes, J., Booth, A., Lewin, S., and Meerpohl, J.J.

Abstract

A considerable proportion of quantitative research remains unpublished once completed. Little research has documented non-dissemination and dissemination bias in qualitative research. This study aimed to generate evidence on the extent of non-dissemination in qualitative research. We followed a cohort of qualitative studies presented as conference abstracts to ascertain their subsequent publication status. We searched for subsequent full publication in MEDLINE, in the Cumulative Index to Nursing & Allied Health Literature and in Google Scholar. We matched abstracts to subsequent publications according to authors, method of data collection and phenomenon of interest. Fisher's exact test was calculated to examine associations between study characteristics and publication. Factors potentially associated with time to publication were evaluated with Cox regression analysis. For 91 of 270 included abstracts (33.70%; 95% CI 28.09%–39.68%), no full publication was identified. Factors that were found to be associated with subsequent full publication were oral presentation (OR 4.62; 95% CI 2.43–8.94) and university affiliation (OR 1.96; 95% CI 1.05–3.66). Compared to oral presentations, studies presented as posters took longer time to reach full publication (hazard ratio 0.35, 95% CI 0.21–0.58). This study shows that it was not possible to retrieve a full publication for over one-third of abstracts. Our findings suggest that where this non-dissemination is systematic, it may lead to distortions of the qualitative evidence-base for decision-making through dissemination bias. Our findings are congruent with those of other studies. Further research might investigate non-dissemination of qualitative studies in other disciplines to consolidate our findings.

Published
2021

21. EPOC Qualitative Evidence Syntheses: Protocol and review template v1

Author

Glenton C, Bohren MA, Downe S, Paulsen EJ, Lewin S, on behalf of Effective Practice and Organisation of Care (EPOC).

Subjects
Cochrane EPOC
Abstract

EPOC Qualitative Evidence Syntheses: Protocol and review template Version 1.1 September 2020 Cochrane Effective Practice and Organisation of Care (EPOC)

Published
2021
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27. Stratified turbulent mixing in oscillating shear flows.

Author

Lewin, S. F. and Caulfield, C. P.

Subjects
KELVIN-Helmholtz instability, TURBULENT mixing, SHEAR flow, INTERNAL waves, REYNOLDS number, OCEAN waves, TURBULENCE, KINETIC energy
Abstract

Motivated by the variation of local shear produced by internal waves in the ocean, we use direct numerical simulations to investigate the effect of a time-dependent shear forcing on the evolution and mixing of turbulence produced by Kelvin--Helmholtz instability (KHI) at high Reynolds number. The forcing is implemented using a tilting coordinate system which causes the background shear to accelerate and decelerate periodically. We demonstrate that, with suitable timing between development of instability and the shear oscillation cycle, turbulence produced by KHI with a decelerating shear mixes in a distinctly different way from the flow with constant background shear, specifically with the energy for turbulent motions extracted from alternative sources. As a result, the total amount of mixing as measured by the change in background potential energy can in fact be significantly larger for flows in which the shear is decelerated, despite the fact that the total kinetic energy in the flow is significantly smaller. The mixing has characteristics more in common with convectively driven rather than shear-driven flows, supporting the argument for an underlying change in the mechanisms triggering the turbulence. [ABSTRACT FROM AUTHOR]

Published
2022
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42. Propagation of Shock Waves of Varying Curvature.

Author

Lewin, S. and Skews, B.

Subjects
SHOCK waves, THEORY of wave motion, CURVATURE, MACH number, CONCAVE surfaces
Abstract

When a shock wave having variable concave curvature propagates, it can develop a kink followed by the development of a reflected shock. A typical example is a plane incident shock encountering a surface with concave curvature, the part of the shock adjacent to the surface curves forward and subsequently develops into a Mach reflection with a Mach stem, shear layer and reflected shock. The physical mechanisms associated with the evolution of the shock profile was evaluated for shock waves with initial profiles comprising a cylindrical arc, placed in-between two straight segments, propagating in a converging channel. The temporal variation of the pressure distribution immediately behind the shock wave was studied using CFD. This revealed a pressure imbalance in the region where the curved (which was initially cylindrical) and straight shock segments meet. This imbalance occurs due to the difference in the propagation behaviour of curved and planar shock waves, and results in the development of reflected shocks on the shock front. The angle at which the channel walls converge, the initial curvature radius, and the shock Mach number, was varied between 40 and 60 degrees, 130 and 190 mm and 1.1 to 1.4, respectively. The variation with time of the pressure-gradient distribution and the maximum pressure gradient behind theshock wave was evaluated. From this, the trajectory angle of the triple points, and the rate at which the reflected shocks develop, was deduced. It was found that when shock waves with larger curvature radii propagate in channels with lower wall angles, the reflected shocks develop at a slower rate, and the triple points follow a steeper trajectory. Consequently, the likelihood of reflected shocks emerging on the shock front, within the duration of the shock propagation, is reduced. This is due to the triple points intersecting the walls, before reflected shocks can fully develop. Similarly, when the shock Mach number is higher, the trajectory angle of the triple points is greater, and they intersect the walls before the reflected shocks can emerge. [ABSTRACT FROM AUTHOR]

Published
2021
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44. Cochrane Qualitative and Implementation Methods Group Guidance paper 2: Methods for assessing methodological limitations, data extraction and synthesis, and confidence in synthesized qualitative findings

Author

Noyes, J., Booth, A., Flemming, K., Garside, R., Harden, A., Lewin, S., Pantoja, T., Hannes, K., Cargo, M., and Thomas, J.

Subjects
education
Abstract

The Cochrane Qualitative and Implementation Methods Group develop and publish guidance on the synthesis of qualitative and mixed-method implementation evidence. Choice of appropriate methodologies, methods and tools is essential when developing a rigorous protocol and conducting the synthesis. Cochrane authors who conduct qualitative evidence syntheses have thus far used a small number of relatively simple methods to address similarly written questions. Cochrane has invested in methodological work to develop new tools and to encourage the production of exemplar reviews to show the value of more innovative methods that address a wider range of questions. In this paper in the series we report updated guidance on the selection of tools to assess methodological limitations in qualitative studies, and methods to extract and synthesise qualitative evidence. We recommend application of GRADE-CERQual to assess confidence in qualitative synthesised findings. This guidance aims to support review authors to undertake a qualitative evidence synthesis that is intended to be integrated subsequently with the findings of one or more Cochrane reviews of the effects of similar interventions. The review of intervention effects may be undertaken concurrently with or separate to the qualitative evidence synthesis. We encourage further development through reflection and formal testing.

Published
2018

45. Applying GRADE-CERQual to qualitative evidence synthesis findings-paper 4: how to assess coherence

Author

Colvin, C.J., Garside, R., Wainwright, M., Munthe-Kaas, H., Glenton, C., Bohren, M.A., Carlsen, B., Tunçalp, Ö., Noyes, J., Booth, A., Rashidian, A., Flottorp, S., and Lewin, S.

Abstract

BACKGROUND: The GRADE-CERQual (Grading of Recommendations Assessment, Development and Evaluation-Confidence in Evidence from Reviews of Qualitative research) approach has been developed by the GRADE working group. The approach has been developed to support the use of findings from qualitative evidence syntheses in decision-making, including guideline development and policy formulation. CERQual includes four components for assessing how much confidence to place in findings from reviews of qualitative research (also referred to as qualitative evidence syntheses): (1) methodological limitations, (2) relevance, (3) coherence and (4) adequacy of data. This paper is part of a series providing guidance on how to apply CERQual and focuses on CERQual's coherence component. METHODS: We developed the coherence component by searching the literature for definitions, gathering feedback from relevant research communities and developing consensus through project group meetings. We tested the CERQual coherence component within several qualitative evidence syntheses before agreeing on the current definition and principles for application. RESULTS: When applying CERQual, we define coherence as how clear and cogent the fit is between the data from the primary studies and a review finding that synthesises that data. In this paper, we describe the coherence component and its rationale and offer guidance on how to assess coherence in the context of a review finding as part of the CERQual approach. This guidance outlines the information required to assess coherence, the steps that need to be taken to assess coherence and examples of coherence assessments. CONCLUSIONS: This paper provides guidance for review authors and others on undertaking an assessment of coherence in the context of the CERQual approach. We suggest that threats to coherence may arise when the data supporting a review finding are contradictory, ambiguous or incomplete or where competing theories exist that could be used to synthesise the data. We expect the CERQual approach, and its individual components, to develop further as our experiences with the practical implementation of the approach increase.

Published
2018

46. The GRADE Evidence to Decision (EtD) framework for health system and public health decisions

Author

Moberg, J, Oxman, AD, Rosenbaum, S, Schunemann, HJ, Guyatt, G, Flottorp, S, Glenton, C, Lewin, S, Morelli, A, Rada, G, Alonso-Coello, P, and GRADE Working Grp

Subjects
Public health, Health systems, GRADE, Evidence to decision, Methodology, Recommendations, Decision-making
Abstract

Objective: To describe a framework for people making and using evidence-informed health system and public health recommendations and decisions. Background: We developed the GRADE Evidence to Decision (EtD) framework for health system and public health decisions as part of the DECIDE project, in which we simultaneously developed frameworks for these and other types of healthcare decisions, including clinical recommendations, coverage decisions and decisions about diagnostic tests. Developing the framework: Building on GRADE EtD tables, we used an iterative approach, including brainstorming, consultation of the literature and with stakeholders, and an international survey of policy-makers. We applied the framework to diverse examples, conducted workshops and user testing with health system and public health guideline developers and policy-makers, and observed and tested its use in real-life guideline panels. Findings: All the GRADE EtD frameworks share the same basic structure, including sections for formulating the question, making an assessment and drawing conclusions. Criteria listed in the assessment section of the health system and public health framework cover the important factors for making these types of decisions; in addition to the effects and economic impact of an option, the priority of the problem, the impact of the option on equity, and its acceptability and feasibility are important considerations that can inform both whether and how to implement an option. Because health system and public health interventions are often complex, detailed implementation considerations should be made when making a decision. The certainty of the evidence is often low or very low, but decision-makers must still act. Monitoring and evaluation are therefore often important considerations for these types of decisions. We illustrate the different components of the EtD framework for health system and public health decisions by presenting their application in a framework adapted from a real-life guideline. Discussion: This framework provides a structured and transparent approach to support policy-making informed by the best available research evidence, while making the basis for decisions accessible to those whom they will affect. The health system and public health EtD framework can also be used to facilitate dissemination of recommendations and enable decision-makers to adopt, and adapt, recommendations or decisions.

Published
2018

48. Cochrane Qualitative and Implementation Methods Group Guidance Series - paper 1: Introduction

Author

Noyes, J., Booth, A., Cargo, M., Flemming, K., Garside, R., Hannes, K., Harden, A., Harris, J., Lewin, S., Pantoja, T., and Thomas, J.

Subjects
education
Abstract

Cochrane Reviews are systematic reviews of primary research in human health care and health\ud policy, and are internationally recognized health care resources for use in a decision-making\ud process. Cochrane works collaboratively with contributors around the world to produce\ud authoritative, relevant, and reliable reviews. Cochrane reviews are commonly used in a guideline\ud development process to determine recommendations for practice. The Cochrane Qualitative\ud and Implementation Methods Group provide methodological advice and guidance to\ud Cochrane as well as leading methodological development to benefit the wider qualitative\ud evidence synthesis community. In this introductory paper 1 we briefly outline the evolution\ud of qualitative and mixed-method synthesis methods, the role of qualitative and mixedmethod\ud syntheses in a decision-making process, and the contribution of qualitative and\ud mixed-method syntheses to understanding complexity in complex intervention reviews. We\ud then introduce a series of papers that provide Cochrane guidance on conducting qualitative\ud and mixed-method evidence syntheses for a decision-making context.

Published
2017

50. Dissemination Bias in Qualitative Research: conceptual considerations

Author

Toews, I., Booth, A., Berg, R.C., Lewin, S., Glenton, C., Munthe-Kaas, H.M., Noyes, J., Schroter, S., and Meerpohl, J.J.

Abstract

When the findings of relevant studies are not disseminated, and are therefore not accessible, data within evidence syntheses may be considered inadequate. In addition, if non-dissemination is systematic rather than random - that is, disseminated studies and findings differ systematically from non-disseminated studies and findings - this will cause bias. Such bias could occur due to several mechanisms, and is referred to by the term dissemination bias. The presence of dissemination bias could impact on our confidence in findings from qualitative evidence syntheses. \ud \ud OBJECTIVE: We explore and discuss the issue of dissemination bias in qualitative research. \ud \ud RESULTS: Based on what is known about dissemination bias in quantitative research, mechanisms causing time lag, language, grey literature and truncation bias are being transferred to qualitative research where they likely also contribute to dissemination bias. These conceptual considerations have informed the proposal of a research agenda. \ud \ud CONCLUSION: Dissemination bias in qualitative research warrants greater exploration, including the extent of non-dissemination and related dissemination bias and how to assess dissemination bias in the context of qualitative evidence syntheses. We also need to further consider the mechanisms through which dissemination bias in qualitative research could occur in order to explore feasible approaches for reducing it.

Published
2017

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