Study area and design
This study was a cross-sectional survey carried out in November and December of 2018 in the Namacurra and Nicoadala districts of the Zambézia province. The districts were selected based on: i) malaria incidence; ii) accessibility; iii) population size similarities; iv) rural type; v) SBC interventions; vi) littoral and coastal. All the localities of these districts were selected for the study. Within each locality, household sample size was calculated by dividing the total sample size of the district by the number of existing localities. Households, the sampling units used in this study, were selected using a systematic random sampling method, after determining the total number in each locality.
Sample
Sample size was calculated based on the equation:
Where: n = sample size; Z = 1.96 (assuming a level of confidence of 95%); p = proportion = 0.5; d = error = 0.05. A total of 768 households were eligible for the study, 384 per district. The households were divided between localities with a size equal to the proportion of households per locality. Additionally, 5 households were added during the data collection process, resulting in a study population of 773 households.
Selection Of Households
In each locality, the households were selected based on the following strategy: first, a household list (population frame) was identified and a number was assigned to each household; then, the sample interval (number of households divided by sample size) was computed and a random number was chosen; finally, from this first random number, households were systematically selected until the calculated sample size was met.
Data Collection And Measurement
A structured questionnaire was pre-tested and administered by previously trained local inquirers. The first section of the questionnaire included socio-demographic questions and the following parts of the questionnaire assessed the head of the household regarding knowledge, attitudes, practices/behaviours, and information channels. The questionnaire was designed in Portuguese, but the interviews were conducted in the local language, Enlowe. The questionnaire was pre-tested in a district similar to the study districts. The head of the household was defined as the primary decision maker in the family and the household and as an individual living in the household and having meals from common cooking facility [15]. A responsible adult, 18-years or older, was appointed to participate in the interview in the absence of the head of the household.
Variables
The variables selected for this study were: place of residence, age, sex, level of education, number of people that live in the household, information channels, knowledge, attitudes, and practices regarding malaria.
Household Inclusion Criteria
The inclusion criteria used to select the households for the study were: i) households from the selected districts, ii) living in the district from 2011 to 2017 (this period covers the SBC interventions funded by different malaria donors), iii) interviewee with at last 18 years of age (head of the household), regardless of gender, iv) the presence of SBC interventions performed by local community actors (volunteers from community structures, school teacher facilitators, activists, and faith leaders), v) mosquito net mass distribution campaigns, and vi) presence of community radios.
Outcomes Of Interest
The measured outcomes were: i) percentage of people who remember hearing or seeing a message about malaria in the previous 6 months, ii) percentage of people with favourable attitudes towards the product (mosquito nets), practices (use of mosquito nets, taking antimalarial), or services (timely demand for health, institutional, or community services when noticing signs and symptoms of malaria), iii) percentage of people who believe that the majority of their friends and communities practice the behaviours (using mosquito nets and seeking counselling and health care services), iv) percentage of people who identify the mosquito as a cause/vector of malaria, v) percentage of people who recognize the main signs and symptoms of malaria, vi) percentage of people who know about treatment for malaria, vii) percentage of people who know malaria prevention measures, viii) percentage of households with at least one mosquito net, ix) percentage of households with 1 mosquito net for every 2 people, x) percentage of people with access to mosquito nets, xi) percentage of people who slept under the mosquito net the night before the survey, and xii) use/access ratio of mosquito nets – behaviour indicator.
Data And Statistical Analysis
After conducting the study, the previously coded questionnaires were reviewed to verify the responses and their validation; later, the data were entered in a database of the program SPSS for Windows, version 23.0 (IBM; Armonk, NY, US). Data analysis was based on descriptive and inferential statistical analysis,