Study area, design, and period
The study was conducted in Nekemte referral hospital and Gida Ayana hospital which are found in East Wollega zone. East Wollega zone is one of the 18 administrative zones of Oromia national regional state and is located western to Addis Ababa. It has an area of 14,255 square kilometers with estimated population of 1,531,380 (one million five hundred thirty one thousand three hundred eighty) as projected from 2007/2008 census. The economy of the people is based on subsistence farming and livestock rearing. There are two hospitals and 58 health centers owned by government in the zone currently [19–22]. A facility based un-matched case–control study was employed from December 3, 2014 –March 25, 2015.
Source and study population
All children aged 6–59 months who were visited/admitted to Nekemte referral and Gida Ayana hospitals for different health care issues during the study period were the source population. All randomly selected children aged 6–59 months were the study population. Those children who had acute malnutrition (Mid-Upper Arm Circumference (MUAC) <12.5 cm, if there is edema) for cases and who had no malnutrition (Mid-Upper Arm Circumference (MUAC) ≥ 12.5 cm, there is no edema) for controls with their corresponding mothers/care takers, respectively.
Children aged 6–59 months who visited or admitted to the hospitals and who had acute malnutrition (MUAC <12.5 cm or with bilateral pitting edema of nutrition origin), with their care takers/mothers who gave informed consent were recruited into the study as cases. Controls include children aged 6–59 months, and attending to the hospitals (MUAC ≥ 12.5, without bilateral pitting edema of nutritional origin) with their mothers/caretakers, who gave informed consent.
Children who had physical deformities (children born without hands due to congenital deformities, wounded, and burned hands) which make anthropometric measurements inconvenient were excluded from the study.
Selection of cases
Children aged 6–59 months who were admitted during the data collection period were allocated to both hospitals depending on previous month’s acutely malnourished children flow. Cases were children with a diagnosis of moderate to severe malnutrition with MUAC of <12.5 cm or bilateral pitting edema of nutritional origin.
Selection of controls
Controls were children without malnutrition (MUAC of ≥ 12.5 cm), without bilateral pitting edema of nutritional origin and were selected from the same hospital from which cases were selected.
Sample size determination
The sample size was computed using Statcalc. application of Epi –Info version 3.5.3. Statistical software with the following assumptions: Proportion of illiteracy among fathers of controls to be 41.16 % and of the cases 58.84 % , 95 % confidence interval, 80 % power of the study, control to case ratio of 2:1 to detect an odds ratio of 2.04 with a 5 % of non-response rate. Thus, the sample size required for the study was 339 (113 cases and 226 controls).
Both hospitals found in the zone were included and 113 children who were acutely malnourished and 226 well-nourished but visited/admitted to the hospitals for other health care issues were selected. Children aged 6–59 months with acute malnutrition were allocated to the hospitals depending on the average previous month’s acutely malnourished children flow to the hospitals.
From previous months on average 27 children with cases of acute malnutrition were reported and during the four months there were 108 children with cases of acute malnutrition at Gida Ayana hospital. Depending up on this; 35 cases and 70 controls were allocated to Gida Ayana hospital and systematic random sampling technique was used to select every 3rd child from 108 children.
Similarly in Nekemte referral hospital from previous months on average 59 children with cases of acute malnutrition were reported in one month and during four months there were 234 children with cases of acute malnutrition at Nekemte referral hospital and systematic random sampling technique was used to select every 3rd child. Depending on this 78 cases and 156 controls were allocated to Nekemte referral hospital. The controls were selected as soon as cases were selected from the same hospital.
Data collection instruments and procedure
Data were collected from all eligible children mothers/care givers by data collectors using interviewer administered questionnaire under close supervision of the assigned supervisors and principal investigator. Anthropometric measurements particularly MUAC was also taken from all children after the proper training and standardizing procedures. Edema was diagnosed if a bilateral depression (pitting) remained after the pressure was released. Once a case was found and his or her care giver interviewed, two controls meeting the criteria were selected and their care givers interviewed. To identify retrospective morbidity of children, mothers were asked about any occurrence of illness during the past two weeks.
A structured interviewer administered questionnaire which was adapted after thorough review of different literatures was used to collect data related to the objectives of the study. The questionnaires were prepared in English then translated to Afan Oromo (local language) and finally back translated to English language by other person who has good command of English and Afan Oromo to check for its consistency. The questionnaire covered a range of topics including socio-economic and demographic factors, child characteristics, child caring practices, maternal characteristics and environmental health conditions. MUAC was measured using easily portable measurement device the armband/tape. For data collection four 10thgrade completed students were recruited. Two nurses from the hospitals were also recruited as supervisors.
Variables of the study
Acute malnutrition (SAM or MAM) in terms of MUAC <12.5 cm, WHZ < −2 SD, and presence of bilateral pitting edema of nutritional origin in under five children were considered as dependent variables in this study. Children with weight-for-height Z-score (WHZ) < −2 SD from the median value of WHO’s 2006 reference data were considered as wasted (acutely malnourished). Socio demographic variables (family size, occupation, and parental education, ethnicity, religion and place of residence); economic status (monthly income, ownership of livestock and farmland); maternal characteristics (age, hand washing, number of under five children); child characteristics and caring practices (sex, age, immunization status, feeding practices, hygiene); health related characteristics (health care seeking, and morbidity status); and community factors (distance and sanitation of water supply) were considered as independent variables.
Data quality control
The data collectors and supervisors were trained for four days and standardized particularly in the proper filling of questionnaire, and the use of the measurement device the armband/tape in order to minimize inter and intra observer errors. Data quality was controlled through conducting a pre-test on5 % of the samples in Gimbi hospital before the actual survey and important modifications were made on the basis of the findings. Data collectors were paired during the data collection to ensure quality of the data. The data collection was supervised by the principal investigator. Every questionnaire was supervised and reviewed for completeness and logical consistency. The completeness of the questionnaire was also checked before data entry. Anthropometric measurement (MUAC) of children was done by trained data collectors using standard procedures.
Data processing and analysis
The data were checked for completeness, coded and entered in to a computer using SPSS for windows version 20 and then edited, cleaned, processed and analyzed. Descriptive analysis was used to describe the percentages and number of distributions of the respondents by socio-demographic characteristics and other relevant variables in the study. In order to investigate the association of independent variables with acute malnutrition both bivariate and multivariate analysis were used. Bivariate analysis was performed on the independent variables and their proportions and crude odds ratio were computed against the outcome variable to identify the factors that were associated with child acute malnutrition. Hosmer–Lemeshow goodness-of-fit was used to test for the model fitness. The variables that showed an association with the outcome variable at the bivariate analysis with p value <0.05 were entered into the final multivariable logistic regression to control for potential confounders. Adjusted odds ratio (AOR) along with 95 % confidence interval was estimated to assess the strength of the association and a P value < 0.05 was considered to declare the statistical significance in the multivariable analysis in this study.
Case: Child with MUAC < 12.5 or presence of bilateral pitting edema of nutritional origin.
Control: child with MUAC ≥ 12.5, without bilateral pitting edema of nutritional origin.
Diarrhea: a child having three or more loose or watery stools per day.
Acute Respiratory Infection (ARI): A child with cough, fast breathing or difficulty in breathing and fever.
Low family income: Households earning monthly income below 50 USD.
Hand washing frequently: Those who wash hands at all activities such as after latrine, before preparing food, before serving food, after cleaning child feces etc.
Hand washing less frequently: Those who do not wash their hands at activities such as after latrine, before preparing food, before serving food, after cleaning child feces.
The study was cleared by the Ethical Review Committee of Wollega University (Ref. No: WU/IEC/32/07). Permission letter was obtained from zonal and woreda health offices of East Wollega zone. Informed verbal and written consents were obtained from the parents/care givers of the children before the interview. Illiterate mothers were consented by their thumb print after verbal consent. Mothers/care givers of children with acute malnutrition were advised on how to prevent and treat it and for those cases that did not begun treatment appropriate link was made to therapeutic feeding centers.