A cross-sectional household survey in Magoe district, Mozambique was used to assess general malaria and ITN perceptions, including perceived ITN response efficacy, self-efficacy to use ITNs, and community norms of net use. Use of ITN among children with access to ITN at the household level in this context is relatively modest with only half of children reporting to have used a net the previous night. This level of net use among children is much lower than the 73% net use that was found in the 2018 MIS. This discrepancy in net use is mostly likely due to the timing of the two surveys; the Magoe survey was conducted at the end of the dry season (in November 2019) when mosquito densities are typically at their lowest, while the 2018 MIS was conducted at the end of the rainy season when mosquito densities, as well as perceived risk of malaria, are typically at their highest. The difference may also be related to the differing sample and timing of the surveys. Socioeconomic status was shown to be a strong predictor of ITN use when households had access to ITN in this study. This finding highlights on going inequity in malaria prevention, despite high and equitable access among the study population. Unexpectedly, higher maternal response efficacy of nets was associated with lower use of nets by children during the dry season. While this result is somewhat surprising, similar phenomena have been shown in other domains, such as student performance, whereby stronger perceptions of self-efficacy or overconfidence is negatively associated with desired outcomes . This phenomenon might arise in this case because the individuals sense that they can achieve their desired outcomes without rigorous use of the intervention as the efficacy is perceived to be high. Storey and colleagues found this precise result in cross sectional data from Nigeria . Overall, other ideational responses were not strongly associated with ITN use among this group where ITN access was universal. This finding suggests that messaging to reinforce the importance of consistent net use (i.e. sleeping under a net every night) in order to achieve the highest level of protection from nets could improve net use in households with a sufficient number of nets, especially during the dry season when mosquito numbers are much lower.
It is well–documented that access to an ITN is one of the most, if not the single most, important determinants of net use [4, 7, 10]. The inclusion criteria for this study ensured that population access to nets was near universal in the study population. While other studies have identified various ideational factors about net use as predictive of use, they generally looked at populations in which net access was not universal . It is possible that ideational factors may work further upstream, mainly by influencing families and households to ensure that they have access to ITNs and thus their impact on net use is largely mediated by net access . If this is the case, then it is not tremendously surprising that in a population where access to ITNs is universal that ideational factors would be less associated with variability in ITN use.
In this study population, the coherence of the ITN ideational scales were only moderate, with Cronbach’s alpha scores ranging from 0.5 to 0.9. The scales, which have also been used in other settings, might need refinement or adjustment for use in different study populations . The scales employed here also include a ‘’Don’t Know” response. Future applications of these or related scales should not include a ‘’Don’t Know” category and rather encourage respondents to respond with the category that most fits their individual perceptions as such responses do not fit easily into the Likert–type responses used in these scales.
Use of nets by children is not necessarily the same as adoption of health behaviours overall, including net use by adults. Ideational models of behaviour change with measurement of ideational factors among mothers may translate imperfectly to choices about net use for their children. Additional constraints to decision–making may be present at the household level, such as a father’s influence or additional older children needing bednets as well. The translation of measurements about a mother’s individual beliefs to health decision making for her children may introduce additional opportunities for ideation and action to diverge. Clearly, a mother’s beliefs and intentions are expected to be highly influential as to child net usage, but it remains to be seen the extent to which these particular measures of ideation can effectively capture this relationship in this setting. Future use of similar scales and analyses should consider household decision-making autonomy and risk-perception as additional ideational factors that may be context-specific. This study did not find significant statistical associations between net use and key ideational factors, but did in fact find an unexpected signifcant negative association between mother’s ITN response efficacy and child net use. The fact that access to ITNs in this population is universal but there were still substantial gaps in ITN use by children under five years old points to as-yet unidentified behavioural factors preventing net use in this population. Future data collection to understand these behavioural barriers could incorporate mixed-methods approaches to complement this study based on the same ideational framework. The population selected for inclusion in this trial was not a representative sample of Magoe District as a whole and as such the results here should not be considered as estimates of district level net use, or of other population level parameters. The associations between net use and other factors however are likely to extend to all households with sufficient access to ITNs within Magoe District. These findings may be helpful in the design of behaviour change communication strategies designed to influence mother-child ITN use patterns in similar settings.