The search strategy yielded 150 published studies, of which 2 duplicate studies were directly removed and 32 studies were excluded due to the year of publication. Upon reading the abstracts, 11 studies presented irrelevant abstracts and were excluded. The next stage was to read the contents of the remaining 105 studies to exclude those which were not related to social systems. We excluded 30 studies on Ecosan technology characteristics and function and 20 studies on Ecosan technological product, composition, and safety. The remaining 55 studies were tested against the technology diffusion model of Rogers (2003). As a result, 14 studies did not exactly indicate any information related to the stage of the technology diffusion model and 7 studies did not present any information on the complexity of Ecosan technology. The remaining 34 studies were compatible with the stages of the innovation model of Rogers (2003) and met the eligibility criteria as the final sample of studies. All 34 reviewed studies were distributed across the same model, based on the criteria of study outcomes as follows: four studies each were presented at the knowledge, persuasion, and decision stages, six studies were considered at the implementation stage and 16 studies were eligible at the confirmation stage (Table 1).
Literature analysis of the complexity of diffusion of Ecosan following five stages of innovation
| Authors and year . | Country . | Study methods . | Knowledge stage . | Persuasion stage . | Decision-made stage . | Implementation stage . | Confirmation stage . | Complexity . |
|---|---|---|---|---|---|---|---|---|
| Jewitt (2011) | UK | Systematic review | a | Ecosan threats and opportunities | a | a | a | Spatial and cultural boundaries |
| Andersson (2015) | Uganda | Participatory action research | a | Participation of Ecosan users | a | a | a | Unclear user guidelines |
| Simha et al. (2017) | India | Quantitative | a | Drivers and hinders of Ecosan uptake | a | a | a | Religious taboos |
| Seleman & Bhat (2016)) | Tanzania | Mixed | a | Feasibility and sustainability of Ecosan | a | a | a | Negative attitude on human faeces |
| Cofie et al. (2010) | Ghana | Quantitative | a | a | a | a | Perceptions and economic benefits | Lack supporting supervision |
| Krause et al. (2016) | China | Quantitative | a | a | a | a | Crop production | Poor application practice of Ecosan products |
| Andersson et al. (2011) | South Africa | SWAT model | a | a | a | a | Failure to maximize Ecosan demand | Insufficiency of Ecosan products |
| Ganiron (2015) | Hong Kong | Review | a | a | a | a | Ecosan system must be regularly monitored | Phobia against the reuse of excreta |
| Haq & Cambridge (2012) | Sweden | System review | a | a | a | a | The co-benefits of Ecosan | Unsafe Ecosan product |
| Zhou et al. (2010) | China | Review | a | a | a | a | Ecosan benefits | Excreta exposure |
| Gao et al. (2017) | China | Review | a | a | a | a | Ecosan acceptability | Environmental constraints |
| Lalander et al. (2013) | France | Quantitative | a | a | a | a | Hygienic quality | Safety issues |
| Taseli & Kilkis (2016) | USA | Review | a | a | a | a | Ecosan closing the loop | Diversification of Ecosan options |
| Pham-duc et al. (2013) | India | Quantitative | a | a | a | a | Ecosan model | On-site contamination |
| Roma et al. (2013) | South Africa | Quantitative | a | a | a | a | Ecosan challenges | Malfunctioning of the pedestal |
| Ekane et al. (2016) | Rwanda & Uganda | Quantitative | a | a | a | a | Low use of Ecosan/UDDTs | Lack of stake holding |
| Kumwenda et al. (2017a) | Malawi | QMRA | a | a | a | a | Health risks | Microbial risks |
| Kumwenda et al. (2017b) | Malawi | Quantitative | a | a | a | a | Infections | Ascaris lumbricoides |
| Dickin et al. (2018) | Burkina Faso | Quantitative | a | a | a | a | Post-implementation | Menstrual pads management |
| Davies-colley & Smith (2012) | Mexico | Case study | a | a | a | a | A bad reputation on Ecosan | Technical support |
| Tumwebaze & Mosler (2014) | Uganda | Intervention study | a | a | a | Sharing Ecosan toilets | a | Privacy and security |
| Magri et al. (2013) | Vietnam | Experimental design | a | a | a | Inactivation of faecal pathogens | a | Long excreta decomposition time |
| Sangare et al. (2015) | Burkina Faso | Experimental setup | a | a | a | Ecosan product on the farms | a | Functionality issues |
| Krause et al. (2016) | Tanzania | Experimental setup | a | a | a | Ecosan as a soil fertility improver | a | Pollution facts |
| Hu et al. (2016) | China | Systematic review | a | a | a | Ecosan affordable | a | Cleaning and reparation of slabs hard |
| Simha & Ganesapillai (2016) | India | Systematic review | a | a | a | Ecosan as nutrient recovery | a | Diversification of fertilizers |
| Chunga et al. (2016) | Malawi | Mixed | a | a | Ecosan choices | a | a | High capital costs |
| Mayo & Mubarak (2015) | Tanzania | Mixed | a | a | Ecosan adoption | a | a | Misuse of ash |
| Fry et al. (2015) | Ethiopia | Mixed | a | a | Ecosan Adoption and values | a | a | Hard excreta emptying |
| Uddin et al. (2014) | Bangladesh | Mixed | a | a | Socio-cultural acceptance | a | a | Anal washing |
| Jana (2011) | India | Review | Traditional knowledge on Ecosan | a | a | a | a | Large scope |
| Tumwebaze & Niwagaba (2011) | Uganda | Quantitative | Knowledge about Ecosan | a | a | a | a | Knowledge gaps |
| Bhardwaj et al. (2017) | India | Qualitative | Female literacy | a | a | a | a | Illiteracy |
| Kumwenda et al. (2016) | Malawi | Qualitative | Knowledge, attitudes and practices | a | a | a | a | Stranger technology |
| Authors and year . | Country . | Study methods . | Knowledge stage . | Persuasion stage . | Decision-made stage . | Implementation stage . | Confirmation stage . | Complexity . |
|---|---|---|---|---|---|---|---|---|
| Jewitt (2011) | UK | Systematic review | a | Ecosan threats and opportunities | a | a | a | Spatial and cultural boundaries |
| Andersson (2015) | Uganda | Participatory action research | a | Participation of Ecosan users | a | a | a | Unclear user guidelines |
| Simha et al. (2017) | India | Quantitative | a | Drivers and hinders of Ecosan uptake | a | a | a | Religious taboos |
| Seleman & Bhat (2016)) | Tanzania | Mixed | a | Feasibility and sustainability of Ecosan | a | a | a | Negative attitude on human faeces |
| Cofie et al. (2010) | Ghana | Quantitative | a | a | a | a | Perceptions and economic benefits | Lack supporting supervision |
| Krause et al. (2016) | China | Quantitative | a | a | a | a | Crop production | Poor application practice of Ecosan products |
| Andersson et al. (2011) | South Africa | SWAT model | a | a | a | a | Failure to maximize Ecosan demand | Insufficiency of Ecosan products |
| Ganiron (2015) | Hong Kong | Review | a | a | a | a | Ecosan system must be regularly monitored | Phobia against the reuse of excreta |
| Haq & Cambridge (2012) | Sweden | System review | a | a | a | a | The co-benefits of Ecosan | Unsafe Ecosan product |
| Zhou et al. (2010) | China | Review | a | a | a | a | Ecosan benefits | Excreta exposure |
| Gao et al. (2017) | China | Review | a | a | a | a | Ecosan acceptability | Environmental constraints |
| Lalander et al. (2013) | France | Quantitative | a | a | a | a | Hygienic quality | Safety issues |
| Taseli & Kilkis (2016) | USA | Review | a | a | a | a | Ecosan closing the loop | Diversification of Ecosan options |
| Pham-duc et al. (2013) | India | Quantitative | a | a | a | a | Ecosan model | On-site contamination |
| Roma et al. (2013) | South Africa | Quantitative | a | a | a | a | Ecosan challenges | Malfunctioning of the pedestal |
| Ekane et al. (2016) | Rwanda & Uganda | Quantitative | a | a | a | a | Low use of Ecosan/UDDTs | Lack of stake holding |
| Kumwenda et al. (2017a) | Malawi | QMRA | a | a | a | a | Health risks | Microbial risks |
| Kumwenda et al. (2017b) | Malawi | Quantitative | a | a | a | a | Infections | Ascaris lumbricoides |
| Dickin et al. (2018) | Burkina Faso | Quantitative | a | a | a | a | Post-implementation | Menstrual pads management |
| Davies-colley & Smith (2012) | Mexico | Case study | a | a | a | a | A bad reputation on Ecosan | Technical support |
| Tumwebaze & Mosler (2014) | Uganda | Intervention study | a | a | a | Sharing Ecosan toilets | a | Privacy and security |
| Magri et al. (2013) | Vietnam | Experimental design | a | a | a | Inactivation of faecal pathogens | a | Long excreta decomposition time |
| Sangare et al. (2015) | Burkina Faso | Experimental setup | a | a | a | Ecosan product on the farms | a | Functionality issues |
| Krause et al. (2016) | Tanzania | Experimental setup | a | a | a | Ecosan as a soil fertility improver | a | Pollution facts |
| Hu et al. (2016) | China | Systematic review | a | a | a | Ecosan affordable | a | Cleaning and reparation of slabs hard |
| Simha & Ganesapillai (2016) | India | Systematic review | a | a | a | Ecosan as nutrient recovery | a | Diversification of fertilizers |
| Chunga et al. (2016) | Malawi | Mixed | a | a | Ecosan choices | a | a | High capital costs |
| Mayo & Mubarak (2015) | Tanzania | Mixed | a | a | Ecosan adoption | a | a | Misuse of ash |
| Fry et al. (2015) | Ethiopia | Mixed | a | a | Ecosan Adoption and values | a | a | Hard excreta emptying |
| Uddin et al. (2014) | Bangladesh | Mixed | a | a | Socio-cultural acceptance | a | a | Anal washing |
| Jana (2011) | India | Review | Traditional knowledge on Ecosan | a | a | a | a | Large scope |
| Tumwebaze & Niwagaba (2011) | Uganda | Quantitative | Knowledge about Ecosan | a | a | a | a | Knowledge gaps |
| Bhardwaj et al. (2017) | India | Qualitative | Female literacy | a | a | a | a | Illiteracy |
| Kumwenda et al. (2016) | Malawi | Qualitative | Knowledge, attitudes and practices | a | a | a | a | Stranger technology |
aNo available suitable information.