Introduction
Studies have shown, particularly in developing countries, that for health innovations to achieve their aims, there is a need for scale up [
1,
2]. Scale up entails making the innovation available to a larger population and/or to new locations through better financing, and provision of material and human resources, as well as an improved public health delivery system [
1,
2]. Studies show that social networks can facilitate both positive and negative behaviors [
3,
4] – either through word of mouth or virtual networks via social media [
5]. Also, social networks can support uptake of health innovation, and thus facilitate scale up [
3,
6].
Although researchers [
4,
6,
7] have demonstrated that social networks can support the uptake of health innovation, there is limited understanding or guidance on the role of social networks in the scale up of community-based injectable contraceptives- an innovation adopted in Nigeria. Uptake of this intervention is particularly important in Nigeria, a country with low contraceptive prevalence rates (CPR) and unmet need for contraception [
8]. CPR is 14.6% for any method (rhythm, withdrawal, traditional methods) and 9.7% for modern methods (pills, condoms, implants, intrauterine devices, injectable contraceptives) [
9,
10], with a significantly lower rate in rural settings [
11,
12]. Furthermore, only 3% of married women in Nigeria use an injectable contraceptive method [
13]. However, the main thrust of Nigeria’s National Policy on Population was to reduce the country’s high rate of fertility (currently 5.5 births per woman) by encouraging voluntary adoption of family planning, in particular, modern contraceptive methods including injectable contraceptive methods [
13]. Injectable contraceptive is the most popular method among women of reproductive age group in Nigeria [
14]. Evidence from other African countries showed that injectable contraceptive was more effective in preventing pregnancies compared to other contraceptives because its effect is long-term and puts the woman in control [
13,
14]. In 2010, a pilot study in Gombe State (one of the 36 states in Nigeria), tested the feasibility of community health extension workers (CHEWs) distributing injectable contraceptives to users at households and other settings outside the health facility with the aim to increase contraceptive prevalence rate [
14]. Following the success of the pilot, the intervention was scaled-up in other parts of Gombe and later extended to another state, with plans to ultimately make the benefits available throughout the country [
14]. Research exploring the potential of social networks in innovation uptake is sparse, especially in low- and middle-income countries (LMICs) like Nigeria [
6,
15].
Background
The community-based distribution of injectable contraceptives by community health extension workers has been implemented in pilot projects around the world, with significant improvement in contraceptive prevalence rate [
16‐
18]. Research has shown that community-based distribution of family planning commodities improves access to and uptake of family planning methods [
19]. This innovation involves the provision of injectable contraceptives to women of reproductive age group by community health extension workers in the community. It has been shown to be safe and effective in meeting couples’ unmet need for contraception in demonstration projects in Kenya, Rwanda, Ethiopia, Malawi and Uganda [
20,
21].
Many health innovations have been shown to improve health [
22]. These include interventions to combat AIDS, malaria, tuberculosis as well as to improve reproductive health [
22‐
24]. Although some health innovations are effective in demonstration projects [
16,
23], they might not be made available to a large part of the population, or, where available, may be inequitably distributed [
14,
16]. Also, there is limited information about how to successfully disseminate, diffuse and scale up such innovations on a wider scale [
16].
Social networks and scale up of innovations
A social network consists of actors joined together through one or more ties or relations [
25]. Through these ties, actors exchange information and also transmit expertise, knowledge, experience, and behaviors [
3]. Social network analysis studies are used to assess various features of social networks, some of which are relevant for this study. For example, density – which is the number of ties forged within a network as a proportion of total possible ties – is a measure of cohesion amongst network actors. Degree centrality describes the position that each actor occupies in a network. In a network, some actors are central or prominent (those with the greatest number of ties to others), while others may be peripheral (those with few ties or direct connections to others). Another network feature is homophily, which is a measure of sameness or how much an actor relates with other actors with similar characteristics [
26]. Furthermore, betweeness centrality measures the number of times an actor connects individuals who may otherwise not be connected in the network [
27,
28]. In particular, this study seeks to find answers to the following questions: Do early adopters share information about the innovation with other women in their social circles? How tightly knit are these social networks and are there prominent actors in them? Who are the women they share with? Do women share this kind of information with those of similar characteristics? What characteristics commonly bind actors in these women’s social networks together? In which social settings do they regularly interact (opportunities for sharing)?
In order to answer the questions above, we utilized social network analysis (SNA) to explore the potential for early adopters of community-distributed injectable contraceptives to influence the uptake of the innovation by new users in their social networks. The early adopters were women of the reproductive age group who had adopted the community-based injectable contraceptives at the time of the pilot study in Gombe state. To the best of our knowledge, no study has explored the role of social networks in the diffusion of injectable contraceptives in Nigeria, especially from users’ perspectives. Thus, this study describes features (density and homophily) of the social networks of early adopters of community-distributed injectable contraceptives and explores the extent to which early adopters talked to / shared information about the innovation with women in their social networks.
In the AIDED model, Bradley and colleagues [
29] conceptualized scale up as a process that entails various interrelated stages. These stages include assessing the landscape, innovating to fit potential users’ interests, developing community support, engaging with users of innovation and devolving in order to enhance innovation spread. According to Bradley et al., [
16] spread of health innovations from early adopters (index users) in low-income countries often occur via their social networks. However, there is a dearth of information on the Devolve component of the AIDED model and how social networks facilitate the scale up of injectable contraceptives among user groups [
30]. The Devolve component entails diffusion of innovation through the peer networks of the initial users [
30]. In addition, Valente, in his review of research evidence, submitted that social networks influence how people adopt new ideas and it may enhance behavioral change, organizational efficiency as well as the diffusion and spread of innovations [
3,
31]. The decision to adopt or reject a new idea is mostly based on subjective evaluations from peers and hardly on research evidence [
32]. Therefore, interpersonal communication channels have been found to be more effective than mass media in the formation and sustenance of attitudes towards an innovation since the diffusion of innovations is essentially a social process entailing the exchange of ideas among people [
32]. Hence the use of social networks in understanding the spread of community-based injectable contraceptives in this study. This SNA study draws from the “Devolve” component of the AIDED model. SNA is a method that enables us to study social networks and how these influence behaviors and spread of innovation [
3].
Discussion
This study revealed that most of the networks have high densities. Also, actors with high degree centrality showed prominence in their networks. In addition, common sources of homophily among actors in networks were ethnicity, age, education, and marriage type. The implications of these findings are discussed below.
According to Haythornthwaite, actors in dense networks communicate more amongst themselves than they do in loose networks [
39]. Since dense networks make for easier communication and organization of activities among actors [
27,
40], it would seem to be easier for the knowledge and use of injectable contraceptives to spread among these networks. This is probably due to a higher degree of trust and support among actors in the network, given that more than half of the alters were family or close friends [
40].
However, if a number of actors in a network are non-users of injectable contraceptives, it might be difficult for these actors to adopt the innovation in a dense network since individual decisions are largely swayed by the common opinion in the network [
27,
41]. According to Prell, [
40] actors in a dense network may embrace incorrect information and could be less open to new information thus limiting other players in the network, and ultimately restricting the dissemination of accurate information about health innovations. This assertion is buttressed by the findings of this study which showed that networks with the highest densities may have either a very high
or very low proportion of injectable contraceptive users, suggesting that actors inspire one another in the decision to use or not to use injectable contraceptive since “everyone knows everyone’s business” [
27]. Thus, it is imperative to get the right message about injectable contraceptives across to potential users of this innovation in these closely-knit communities.
In dense networks like in this study, each actor relates with every other actor in the network and no particular person is prominent [
40]. Thus, the use of injectable contraceptives is more likely due to group influence than individual decisions by members of the network [
27]. Also, in a very dense network, any of the actors in the network could easily become a leader championing the spread of the innovation within the network [
3,
27]. Thus, the network is robust and resilient and not dependent on few key players [
40]. Conversely, any one of the players could also be a source of false information about injectable contraceptives, thereby slowing down its adoption and use in the network. This means that in networks with high densities, there are no information “gatekeepers” that other actors can rely on to get connected to the network [
27]. Likewise, about a quarter of the egos were not prominent in their networks. Consequently, the egos might not necessarily be the most popular or most active in the spread of information about injectable contraceptive use since most of the networks are resilient and not centralized around a few actors [
40]. Also, some of the alters might be early adopters themselves.
While it is not possible to refer with certainty to peripheral actors as links to other networks, because the study focused on ego networks, nevertheless, these outliers may have links to other networks. This so-called “strength of weak ties” [
42], suggests that the peripheral actors could be formidable players in the diffusion process by serving as conduits through which networks associated with them get pertinent information from the environment.
Furthermore, our study revealed that actors with high degree centrality tend to also have high betweeness centrality. This suggests that actors with high degree centrality were relatively more prominent in the network and able to control the flow of information about injectable contraceptives [
27,
28]. Since most actors in this study with high betweeness centrality were injectable contraceptive users, this may have a positive ripple effect on the spread of the innovation in these communities. Actors with high betweeness centrality might be useful as peer educators since they are able to act as ‘middle men’ between other actors in their networks and possibly link their network to other groups [
43]. Since the majority of the actors with high betweeness centrality in this study were users of community-based distributed injectable contraceptives, they may also act as “champions” and opinion leaders in their communities [
3]. These actors might be able to play this role because they usually control the flow of information in the network due to their ties to several other actors; thus they are able to organize and spread information about injectable contraceptives to the whole network [
40].
In addition, few actors who have high betweeness centrality in some networks in the study were not users of injectable contraceptives. This may have implications for the quality of information shared in these networks about injectable contraceptives [
27]. It may also mean that actors who perhaps control information about injectable contraceptives were not necessarily users themselves. This may have a negative influence on the adoption and use of injectable contraceptives in such types of networks.
Moreover, most of the networks in this study were homophilic with respect to ethnicity, age, education, and marriage type. Although, the homophily due to ethnicity observed in this study could be because Hausa is the major ethnic group in the research area. Ethnicity has been described as the greatest source of homophily in social networks followed by age, religion, education, occupation and, gender [
7]. Ethnicity has also been considered as an important determinant of social group membership [
7,
44]. Homophily from race and ethnicity has been reported to permeate marriage, work, friendship, acquaintanceship, to those in whom individuals confide or discuss important matters with before making their decisions [
7,
45]. Thus, working through natural groupings may help to facilitate the diffusion of information and better uptake in the process of scaling up of community-based injectable contraceptives in Gombe and similar communities. At the same time, given that conflict in Gombe State might also be sustained through networks that promote religious and sometimes ethnic homophily, the use of such networks to support the scale up of community-based distributed injectable contraceptives requires political sensitivity and care.
In this study, actors preferred to interact and share information about injectable contraceptives within their age groups. Homophily resulting from age homogeneity has been reported to be long-lasting and usually very strong, probably because these ties often start from childhood [
7,
46]. In addition, just as it was found in this study, education and occupation (which are principal determinants of social class in many contexts, including Gombe), have been shown to demonstrate strong homophily in social networks [
7]. Education, in particular has been reported to influence the uptake of health innovations [
47,
48]. Thus, these characteristics – age, education, and occupation – should be considered when engaging peer educators in the diffusion of innovations like the community-based injectable contraceptives. However, one drawback of homophilic networks is that it is easier for the network to be contaminated with inaccurate or false information or myths about injectable contraceptives, since the actors in the networks have related sources of knowledge [
40].
Nevertheless, this study is limited by the subjectivity of egos as information obtained was solely from the egos’ points of view. Still, it is this very subjectivity which also provides valuable data and enables a better understanding of the influence of network phenomenon – themselves subjective - on uptake and diffusion of health innovations. In addition, almost all alters and egos in this study were married thereby limiting the scope of the application of these findings.
Conclusion
This study shows the application and feasibility of ego social network analysis in identifying and disseminating health innovation through natural groupings in the community. It also illustrates how communication and social interactions among women of reproductive age might influence the uptake and diffusion of community-based injectable contraceptives by others. Additionally, this work shows how the exploitation of network phenomena in homophilic and dense networks may have positive health externality such as passive diffusion of health innovations past the point of introduction [
49]. The interrelatedness of network members’ decision to adopt a health innovation was also illustrated by the findings of this study.
Thus, it is recommended that health messages about the community-based distribution of injectable contraceptives be carefully considered for accuracy and appropriateness, before being disseminated in these closely-knit communities. Also, highly connected or prominent individuals should be identified in the communities to serve as peer educators or “champions” in the scale up process. These champions should be identified within different groups for example marital, ethnic, age, educational, and employment groups, since community members tend to interact more according to these groupings.
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