Farmer Field Schools for Improving Farming Practices and Farmer Outcomes: a Systematic Review
Total Page:16
File Type:pdf, Size:1020Kb
Campbell Systematic Reviews 2014:6 First published: 01 September 2014 Search executed: October 2012 Farmer Field Schools for Improving Farming Practices and Farmer Outcomes: A Systematic Review Hugh Waddington, Birte Snilstveit, Jorge Hombrados, Martina Vojtkova, Daniel Phillips, Philip Davies, Howard White Colophon Title Farmer Field Schools for Improving Farming Practices and Farmer Outcomes: A Systematic Review Institution The Campbell Collaboration Authors Waddington, Hugh Snilstveit, Birte Hombrados, Jorge Vojtkova, Martina Phillips, Daniel Davies, Philip White, Howard DOI 10.4073/csr.2014.6 No. of pages 335 Citation Waddington, H, Snilstveit, B, Hombrados, J, Vojtkova, M, Phillips, D, Davies, P and White, H. Farmer Field Schools for Improving Farming Practices and Farmer Outcomes: A Systematic Review Campbell Systematic Reviews 2014:6 DOI: 10.4073/csr.2014.6 ISSN 1891-1803 Copyright © Waddington et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Contributions The review was undertaken by Jorge Hombrados (JH), Daniel Phillips (DP), Birte Snilstveit (BS), Martina Vojtkova (MV) and Hugh Waddington (HJW). HJW and BS developed the study protocol. HJW led the quantitative effectiveness synthesis and compiled the overall systematic review report. BS led the qualitative synthesis of barriers and enablers. JH, BS, MV and HJW conducted the search, using EndNote reference management software. Decisions on inclusion for impact evaluation studies were made by JH and HJW, with conflicts resolved through discussion and consensus. Decisions on inclusion for qualitative impact evaluation studies were made by BS and MV, with conflicts resolved through discussion, with Philip Davies (PD) acting as an arbiter. Qualitative study coding was carried out by BS, MV, JH and DP, while critical appraisal and effect sizes estimation were undertaken by JH and HJW. Howard White (HW) and PD provided technical support. DP also undertook the portfolio systematic review reported in Appendix A, with support from Gracia Pacillo (IFAD) and HW. Editors for Editor: Sandra Jo Wilson this review Managing editor: Sean Grant Support/funding Millennium Challenge Corporation (MCC) Potential conflicts We are not aware of any vested interest in the outcomes of this review, nor of interest any incentives to represent findings in a biased manner. Corresponding Hugh Waddington authors International Initiative for Impact Evaluation (3ie) London International Development Centre London WC1H 0PD E-mail: [email protected] Birte Snilstveit International Initiative for Impact Evaluation (3ie) London International Development Centre London WC1H 0PD E-mail: [email protected] ii Campbell Systematic Reviews Editors-in-Chief Arild Bjørndal, The Centre for Child and Adolescent Mental Health, Eastern and Southern Norway & University of Oslo, Norway Julia Littell, Bryn Mawr College, USA Editors Crime and Justice David B. Wilson, George Mason University, USA Education Sandra Wilson, Vanderbilt University, USA International Birte Snilstveit, 3ie, UK Development Hugh Waddington, 3ie, UK Social Welfare Nick Huband, Institute of Mental Health, University of Nottingham, UK Geraldine Macdonald, Queen’s University, UK & Cochrane Developmental, Psychosocial and Learning Problems Group Methods Therese Pigott, Loyola University, USA Emily Tanner-Smith, Vanderbilt University, USA Managing Editor Karianne Thune Hammerstrøm, The Campbell Collaboration Co-Chairs Crime and Justice David B. Wilson, George Mason University, USA Martin Killias, University of Zurich, Switzerland Education Paul Connolly, Queen's University, UK Gary W. Ritter, University of Arkansas, USA Social Welfare Jane Barlow, University of Warwick, UK Brandy R. Maynard, Saint Louis University, USA International Peter Tugwell, University of Ottawa, Canada Development Howard White, 3ie, India Methods Ariel Aloe, University of Northern Iowa, USA Ian Shemilt, University of Cambridge, UK The Campbell Collaboration (C2) was founded on the principle that systematic reviews on the effects of interventions will inform and help improve policy and services. C2 offers editorial and methodological support to review authors throughout the process of producing a systematic review. A number of C2's editors, librarians, methodologists and external peer- reviewers contribute. The Campbell Collaboration P.O. Box 7004 St. Olavs plass 0130 Oslo, Norway www.campbellcollaboration.org iii Table of Contents LIST OF FIGURES AND TABLES 7 LIST OF ABBREVIATIONS 9 AUTHORS’ CONCLUSIONS 12 EXECUTIVE SUMMARY 14 Background 14 Objectives 14 Study selection criteria 15 Search strategy 15 Data collection and analysis 16 Results 17 Implications for policy and programmes 18 Implications for research 20 SUMMARY OF FINDINGS TABLES 22 1 BACKGROUND 26 1.1 Description of the problem 26 1.2 Description of the intervention 27 1.3 How farmer field schools are supposed to work 32 1.4 Why this review is needed 35 2 AIMS AND REPORT STRUCTURE 39 3 APPROACH 42 3.1 Study selection criteria 42 3.2 Search strategy 46 3.3 Data collection and analysis 48 4 RESULTS OF EFFECTIVENESS SYNTHESIS 57 4.1 Search results 57 4.2 Study descriptive information 58 4.3 Assessment of study validity 64 4.4 Meta-analysis results 78 5 RESULTS OF QUALITATIVE SYNTHESIS 116 5.1 Search results 116 4 The Campbell Collaboration | www.campbellcollaboration.org 5.2 Study characteristics 117 5.3 Synthesis results 129 6 INTEGRATED SYNTHESIS 142 6.1 Intermediate outcomes 144 6.2 Final outcomes 149 6.3 Diffusion to non-participating neighbour farmers 151 6.4 Authors’ conclusions 153 7 IMPLICATIONS 155 7.1 Implications for policy 155 7.2 Implications for programme implementation 156 7.3 Implications for research 158 7.4 Limitations of the review 160 7.5 Deviations from protocol 161 8 SUPPORT AND AUTHORSHIP 162 9 REFERENCES 165 9.1 Included studies of effects (review question 1) 165 9.2 Included qualitative studies (review question 2) 180 9.3 Studies excluded from synthesis 183 9.4 Additional references 209 APPENDIX A 216 Global project portfolio review 216 APPENDIX B 244 Example search strategy 244 Record of database searches 245 Record of internet searches 246 Journals handsearched 248 Reasons for exclusion of marginal studies 249 Data collection codes 254 APPENDIX C 257 Critical appraisal methods 257 APPENDIX D 265 Effect size calculations 265 Synthetic effect sizes 266 Meta-analysis of bivariate and partial effect sizes 266 APPENDIX E 269 Included effectiveness study descriptives 269 Detailed outcomes reported 280 APPENDIX F 287 5 The Campbell Collaboration | www.campbellcollaboration.org Results of critical appraisal: impact evaluations 287 Results of critical appraisal: qualitative evaluations 295 APPENDIX G 296 Meta-analyses by programme name 296 Meta-analyses including all standard errors corrected for possible unit of analysis errors 299 Meta-analysis findings: additional analysis 306 APPENDIX H 311 Descriptive synthesis of findings from qualitative studies 311 6 The Campbell Collaboration | www.campbellcollaboration.org List of Figures and Tables Figure 1 Components of a farmer field school intervention ...................................... 28 Figure 2 Technologies incorporated in farmer field school curricula (percentage of projects) ...................................................................................................................... 30 Figure 3 FFS curricula and complementary components .......................................... 31 Figure 4 Farmer field school hypothesised causal chain ........................................... 33 Figure 5 Coverage of farmer field schools in low- and middle-income countries (LMICs) ...................................................................................................................... 36 Figure 6 Cumulative number of farmer field school projects implemented .............. 36 Figure 7 Review process ............................................................................................. 41 Figure 8 Quantitative synthesis search results .......................................................... 58 Figure 9 Characteristics of programmes included in review of effects ...................... 63 Figure 10 Summary of risk of bias appraisal for effectiveness studies ...................... 66 Figure 11 Kernel density histograms showing farmer characteristics ....................... 74 Figure 12 Funnel graphs by outcome ......................................................................... 76 Figure 13 Knowledge outcomes for FFS participants and neighbours versus non-FFS comparison ................................................................................................................. 79 Figure 14 Knowledge outcomes for FFS participants by risk of bias status .............. 81 Figure 15 Pesticide use for IPM/IPPM FFS participants and IPM neighbours versus non-FFS comparison farmers .................................................................................... 86 Figure 16 Pesticide use for FFS participants and neighbours excluding high-risk-of- bias studies .................................................................................................................88 Figure 17 Beneficial practices adopted by IPM and other curricula FFS-participants ...................................................................................................................................