Study site and sampling procedures
Mkuranga district is located at eastern part of Coast region, Tanzania. It has a population of 222,921 distributed in a total of 18 wards. Four wards are categorized as semi-urban and hence were excluded from the sampling frame. From a list of 14 rural wards in Mkuranga district, two wards namely Nyamato and Panzuo were randomly selected. Five villages were randomly selected from the list of villages in each ward. Thus a total of 10 villages participated in the project. The selected villages from Nyamato ward were: Nyatunduru, Mkiu, Mvuleni, Mkanoge, and Kilimahewa Kusini. Villages selected from Panzuo ward were: Kibuyuni, Mkruwili, Nyatanga, Mbulani and Kinzae. Each village executive officer was asked to provide a list of households with at least one child below the age of 5 years. Using the list provided by village executive officer, 60 households from each village were randomly selected.
Study population and Sample size
A cross sectional study design was conducted between August and October 2013. A total of 600 households were selected for this study. Heads of households and under-fives were the study population.
Data collection method and analysis
Interviews with heads of households and observations were the methods of data collection employed by this study.
One research assistant visited between 15 and 20 households and conducted interviews with heads of the households. In the event head of household was not present, any member of household who aged 18 years or above was interviewed. The data collection tools were pre-tested in Kisarawe 2-weeks prior to the survey. The questionnaire was designed to capture respondents’ knowledge on causes of diarrhea, water, hygiene and sanitation, and on information on occurrence of episodes of diarrhea among children below the age of five years.
Knowledge on causes of diarrhea was assessed by 7 items which had yes and no responses. The final score was obtained by summing the items and then dichotomized into less and comprehensive knowledge.
Water, hygiene and sanitation education score was obtained by summation of 5 items that asked if the respondent had or had not received education on construction of improved latrine, environmental cleanliness, treating drinking water, safe storage of drinking water and avoiding water recontamination.
The respondent was asked when he/she wash his/her hands. There were 9 items with yes and no responses. The total hygiene score was obtained by summation of these 9 items and then dichotomized into satisfactory and unsatisfactory hygiene.
Sanitation score was constructed by summation of four main observations around the household. These included presence or absence of feaces around the homestead, presence or absence of latrine, presence or absence of utensil drying rack, and whether the latrine and environmental cleanliness was satisfactory or not. Presence was coded 1 and absence 2. Originally, latrine and environmental cleanliness were scored in a 4 Likert scale. Using a checklist, data collector scored 1 if latrine and environmental cleanliness of the household and latrine was very satisfactory, and 4 if latrine and environmental cleanliness very unsatisfactory. After summation of latrine and environmental cleanliness, a dichotomized variable was constructed. Then all items for sanitation variable were summed and dichotomized into satisfactory coded 1 and unsatisfactory coded 2. Respondent was asked if the child (name of child) had diarrhea in the previous seven days. If yes respondent was asked how long the diarrhea lasted (number of days with diarrhea). In addition, respondent was asked on which day or days the child had diarrhea. This question was asked just to counter check the duration of the diarrhea. To get the information of number of episodes of diarrhea the child had, respondent was asked how many times on (the day) the child defecate loose/fluid stool? Same question was asked if the child had diarrhea for more than one day.
Wealth index was assessed as an indicative of socioeconomic status according to a standard approach in equity analysis [12]. Household assets such as house, toilet, land, radio, motorcycle, bicycle, car, phone, cow, pig, goat, sheep, donkey, chicken and duck were recorded as 1 “available and functioning” and 0 not available or available not functioning. Use of sources of energy for cooking i.e. electricity, kerosene oil, fire woods, gas and solar were recorded as 1 “yes” or 0 “no”. Assets and sources of energy for cooking were analyzed using principal components analysis (PCA). The first component resulting from the analysis was used to categorize households into four approximate quintiles of wealth ranging from the 1st poorest to the least poor 4th quintile.
The data was analyzed using SPSS version 17. Continuous variables were summarized into mean and standard deviation while categorical ones were summarized into proportions. Chi- square test and multi nominal logistic regression were applied to determine factors influencing knowledge of causes of diarrhea. The dependent variables were prevalence and knowledge on causes of diarrhea while socio-demographics, WASH education, hand washing practices and observed sanitation were independent variables. The level of statistical significance was set at p < 0.05.
Diarrhea prevalence
Diarrhea was defined as the passage of three or more loose or liquid stools per day [13]. To minimize recall bias, Benjamini and his colleagues suggested that studies should measure caregiver reported illness with a 7 day recall [14]. We chose recording diarrhea during a 7-day period to avoid information bias in diarrhea prevalence. In most circumstances, applying a 7-day recall period using point prevalence data may be the preferred choice for measuring prevalence [15]. We calculated the prevalence of diarrhea as the percentage of children suffering from diarrhea assessed during a 7-day period.
Ethical considerations
Ethical clearance to conduct the study was obtained from the Medical Research Coordinating Committee (MRCC) through National Institute for Medical Research (NIMR) Secretariat in Tanzania. Permission to undertake the study at the selected wards was obtained from the District and local government authorities. The study respondents were also asked for their consent and choose to participate voluntarily after getting clear message following the informed consent process.