Study area and period
This study was conducted Gabiley town, which is located 58 kilometers to the west of capital city of Hargeisa Somaliland. Based on the report from ministry of national planning and development in 2016 the total population of Gabiley was 40,000 (17). The hospital is found in Gabiley town, It is the only governmental hospital in the town rendering a range of medical, maternal, and child health services including delivery services, and various inpatient and outpatient healthcare services. Facility based an unmatched case control study was conducted in Gabiley, which is located in the western part of Somaliland from July 1 to August 31, 2022
Sample size determination and sampling techniques
The sample size is determined using a proportional difference approach for case-control study using Epi-Info statistical software package (Version-7) taking into account maternal anemia as main exposure variable and considering 95% confidence level, 80% power of the study and control to case ratio of 2:1 for estimating low birth weight. As such, I considered that the percent of controls exposed (having anemic mothers) among the controls was 11.6% (39). Assuming a 15% difference (increase) in cases that is assumed in advance, proportion of cases with exposure became 26.6% producing the least extreme Odds Ratio of 2.76 to be detected. Accordingly, after adding 15% non-response rate to each, 100 cases and 200 controls were estimated making a total sample size 300 subjects to be included in the study.
Consecutive sampling technique was employed to reach the study participants. The first low birth weight (birth weight < 2500 grams) case was considered as the starting participants then the next two normal birth weight (birth weight ≥ 2500–4000 grams) were considered as controls. For each low birth weight the next two deliveries with birth weight ≥ 2500–4000 grams was considered as controls and procedure were continued in that way until calculated sample size was achieved.
Data collection tools and procedures
The data was collected using a structured questionnaire by interviewing mothers, Anthropometric measurement of the mothers and the newborns and reviewing medical records. Data was collected by three trained midwives and three nurses working in labour ward using structured questionnaire which was adapted from previous literature (9,11–13,24,33). The interviews were conducted at health facility after the mother give birth and the neonate weight were measured within 1 h of delivery.
One first degree public health professional supervised data collection in health facility while the principal investigator had the overall role of facilitating research works during data collection.
Anthropometric measurement
The weights of the newborns were measured within 1 hour after birth using a balanced digital Seca scale by rounding to the nearest 100 g. The scale was always used to check and zeroed before weighing each newborn. The mid-upper arm circumference (MUAC) of the mother was measured after delivery using flexible non-stretchable standard tape measure. The circumference was measured at the mid-point between the tip of the acromion process of the scapula and olecranon process of the ulna. Measurements were taken from the left arm while it was hanging and relaxed. The measurement was taken two times from each mom and then the average was calculated and recorded to the nearest 0.1 cm.
First trimester maternal weight was measured by using digital Seca scale and maternal height was measured by using a stadiometer to the nearest 0.1 cm.
Hemoglobin level
First trimester of hemoglobin level of each mother was taken from her health card as hemoglobin is routinely done for each mother receiving ANC services at health facility.
Reviewing medical records
The medical records of the mothers were reviewed and relevant information including last-normal menstrual period, ultrasound dating of pregnancy, previous obstetric complication, Anti Natal Care during the current pregnancy and maternal weight during pregnancy were extracted to the questionnaire.
Data quality assurance
Questionnaire was prepared in English and translated to Somali language and back translated to English to keep the consistency of the questions and increase understanding with respondents. Both supervisor and principal investigator closely followed the data collection process. The questionnaire pretested on 5% of the sample size in Umulkalkaal general hospital out of the study area before the actual data collection is implemented. The necessary amendment and corrections was made based on the pretest findings. Training was given for data collectors and supervisors. During the course of the data collection, data collectors were supervised at site. The collected data was checked for completeness and consistency on daily basis by principal investigator and supervisor.
Data Processing and Analysis
Data was cleaned using EpiData version 3.1 (EpiData Association, Odense, Denmark) and exported to the Statistical Package for Social Sciences (SPSS) version 25 software (SPSS Inc. Chicago, IL, USA) for analysis. The analysis part was involved descriptive statistics using standard statistical parameters such as frequency, cross-tabs and percentages and to assess association between birth weight and independent variables logistic regression (bivariate and multivariable) analyses were undertaken. Variables with a P-value of less than 0.25 in the bivariate analysis were considered as a candidate for the multivariable analysis. The extant of association between the different variables related with low birth weight was measured using (OR) at 95% CI. Statistical significance was considered at P-value of less than 0.05.
Ethical considerations
Ethical clearance was obtained from Institutional Review Board (IRB) of Dire Dawa University. Letter of cooperation was obtained from Gabiley regional health Bureau. Informed, voluntary, written and signed consent was taken from the mothers and facility head for both interview and anthropometric measurement of the selected mothers. To ensure confidentiality, their names and other personal identifiers was registered in the format. Objective of the study, right and benefit of the study participants were explained. For participants who were under 18, consent was sought from their guardians (husband, her father or her brother) and the participant provided a written assent to take part in the study. The guardian signed the assent form before the interviews were conducted.