The aim of this study was to explore the impact of incentives on citizen scientists involved using the HumBug mosquito detection tool, specifically to assess whether airtime incentives motivate participants to record and upload mosquito data. We hypothesized that the provision of airtime incentives would increase the motivation for their participation, resulting in an increased number of nights of successful recording and uploading acoustic data. Overall, our results suggest that the participants in the control group recorded and uploaded data for more nights than did those in the incentive group. A previous study conducted in Malawi assessed whether providing incentives would motivate participants to take their HIV tests. This study showed that giving participants incentives increased their desire to seek HIV results [38]. However, a previous study conducted in Peru assessed whether providing incentives for participation in a vector-control campaign undermines the natural desire of community members to participate. The study showed that providing incentives did not affect the natural desire for participation; nevertheless, it was found that incentivized participants were actually more likely to continue participating in the campaign after the incentives were removed. The authors suggest that incentivizing participation in public health campaigns can be an effective way to increase engagement without undermining intrinsic motivation [25].
This study also demonstrated the relationship between different demographic variables and the number of nights of data recording and uploaded. The study revealed differences in performance in terms of recording and uploading data in the different villages. In Mavimba and Milola, participants in the control group recorded and uploaded data more often during the night than did those with incentives. However, in Minepa and Kivukoni, participants who received incentives performed better than did those in the control group. Additionally, for the participants’ age, this study found that the control group in the age groups ‘younger than 30’ and ‘40–49 years’ recorded and uploaded data on more nights than did the incentive group. Younger participants were more likely to have knowledge of using smartphones than older participants were. This could explain why the younger 30 participants performed even without incentives compared to the older 50 years old participants. The farmers were highly motivated by incentives; this group tends to migrate to their farms for a couple of days [27], and these villages also have two seasons of farming (the rainy season and dry season using irrigation systems), which might hinder their performance. However, compared with the incentive group, the control group in the business category recorded and uploaded data on more nights. The contrasting results between the two groups could be related to the fact that the farmers’ incomes are seasonal, so any incentive could help them improve their life. Nevertheless, businesspeople accumulate income on a daily basis, so such incentives might not affect their intrinsic motivations as much as they do for farmers. This study also revealed differences in performance in terms of gender. The findings showed that female participants in the control group recorded and uploaded data more often on nights than male participants, whereas those in the incentive group performed better. In this study area, the culture forces women to be responsible for all household activities, while men are responsible for providing for all family needs. This might also explain why women performed better without incentives than men did. Additionally, in terms of income levels, those with incomes higher than 100,000/=Tshs in the control group performed better than did those with incomes lower than 100,000/= Tshs. This is also an indication that those with earnings are more likely to work even without considering any incentives. However, for education level, compared with participants with higher education levels, those with primary and secondary education in the control group recorded and uploaded data more nights.
The importance of using citizen science in mosquito surveillance and control programs has been demonstrated in several previous studies [18–20, 22, 39, 40]. For example, Low et al. [18] highlighted the benefits of using citizen science in vector control efforts to increase participation in hard-to-reach locations, improve data collection and analysis, and minimize the time frame for data collection [19]. In our present study, citizen scientists were involved in recording and uploading the flight tones of mosquitoes using the MozzWear smartphone app. During the FGD, the study showed that the participants were willing to participate in the study, as they desired to be part of the study on malaria elimination and wanted to gain knowledge on mosquito identification by the end of the study. This was also observed, for example, as female participants with no incentives recorded and uploaded data for more nights than did those who received incentives. These reasons are consistent with those mentioned by other citizen participants in previous studies involving addressing issues that hinder their community's health and wellbeing [41–43]. Participants were willing to take part in the study even without receiving incentives. Previous studies have also indicated that citizens are willing to take social responsibility for addressing concerns, especially when solving problems that result in a loss of life, such as disease [41, 43]. In this study, the participants expressed that they needed support to make the trial successful. They mentioned that solar chargers or power banks are needed for charging phones, especially during the rainy season, since power cuts are frequent and fearing hinders recording and uploading of data.
Moreover, before commencing the study, participants anticipated some of the challenges that they may face during the study, including lack of electricity in their household for charging their phones, seasonal migration to farms during the rainy season, phones to be stolen, lack of knowledge about using smartphones to record mosquito sounds and droughted information about being given feedback about the findings of the research by the research team [35]. Therefore, in the present study, participants were provided with a weekly mobile phone charging cost of 500/= Tsh to enable them to record and upload the data successfully. Participants were asked not to travel with the smartphones provided by the study since they were only allowed to record at the consented household and villages; hence, a requirement to take part in the study was that each participatory household should have at least two adults so that one of them is absent and the other person can record and upload the data. This was done accordingly by the participants, and there was no problem with this. Additionally, three phones were stolen, as highlighted by participants at the beginning of the study, and the research team immediately replaced the phone to avoid delays in recording and uploading the data. Regarding the participants’ familiarity with smartphone usage, the study revealed that after providing them with training and user manuals, they were able to record with minimal errors. For the case of feedback sessions, after completing the study, the research team returned to the villages, conducted the feedback sessions, provided the findings and discussed the way forward.
An important finding from this study is that citizens wanted to remain informed about the study's progress and receive feedback at the end. In the past, the researchers collected data from their villages and never returned to explain what was found during the study. As such, participants expressed a desire to learn about their achievements and any significant problems that were discovered so that they could take appropriate action. Moreover, the participants highlighted the need to be treated courtesy and respectfully, which was confirmed during this study. The participants also emphasized the need for cooperation between researchers and citizens to address serious mosquito-related problems. Previous studies have also indicated the importance of providing feedback to communities after they accomplish their objectives [43]; this process builds trust and strong relationships among researchers and communities. Addressing the issue of feedback at the end of this study, the research team provided feedback to participants and village leaders. Through feedback sessions, the research team provided education on how the community would reduce mosquito biting and hence malaria transmission.
The study also demonstrated that airtime can be sent directly to participants via companies that provide this service. Each participant in the incentive group received 23,000/= Tshs every four weeks (4 days of recording and uploading data). This airtime was sent directly to participants' personal mobile phones. This service was provided by Beem Africa, and there were no complaints from participants about the services. This service also minimized the cost of operation, such as by hiring a car to travel to the villages to distribute airtime. This approach was also used since the study relied on leaving the participants to monitor mosquitoes on their own and recording and uploading the data without assistance during the length of the study. Thus, paying the incentive via Beem Africa helped us to minimize our presence in the villages.
Recognizing the potential of the citizen participants, this study evaluated their experience taking part in mosquito sound recording and uploading the data. The study showed that the information provided to citizen participants helped them to easily record and upload the data. Most participants in the incentive group indicated that they had received a suitable amount of airtime credit, although few suggested that the incentive was not enough in the future. Researchers should consider increasing the amount and preferring cash more than airtime. Participants across both trial groups reported that it was easy to record and send the data using the MozzWear app, although some reported problems with uploading the data. Since uploading mosquito data depends on a viable internet connection, villages that were further away from the internet tower, such as Kivukoni, Mavimba and Milola, had more problems in uploading the data, and they had to move to places where they could obtain better connections. Many participants reported that they would like to upload the MozzWear app to their personal mobile phones in the future, and all the participants of the study were ready to take part in future studies.
Our study has several limitations. While citizen participants were recording and uploading mosquito flight tone data, some of the participants were using their mobile phones for personal reasons despite being asked not to do so. Indeed, some of the participants uninstalled the MozzWear application (although the phones were locked), assuming that at some point, the participants could use the smartphone for personal use, hence destroying the whole system of recording mosquito sounds. The study also showed that some participants installed new applications that were not on the phones when they were deployed. Some of the smartphones ended with broken screens, while others had issues with the charging system, causing a factory reset. Finally, as noted by some participants in the initial interviews, three phones were stolen. However, the main issue encountered was Internet connectivity, especially for villages far from the Internet Tower. This issue was raised during the participants’ experience survey conducted at the end of the study.