Aim, design, setting and sampling
This systematic study primarily focuses on assessing the relationship between rural-urban migration and uptake of (SRH) services among street children in Kampala Capital City, Uganda. A cross-sectional study, involving face-to-face interviews, was conducted among children aged 12 – 24 years who; 1) have continuously stayed for at least 3 months in Kampala capital city prior to the study, 2) spend most of their time on the streets of Kampala capital city, and 3) consented to participate in the study were enlisted. Participants who are unable to provide the required information either due to illness were excluded. Being a hard-to-reach population, we used a two-stage cluster sampling for floating populations (venue-based time-space sampling). First, in order to identify the parishes and geographic locations/venues where street children congregate during daytime, we conducted a rapid mapping exercise in three of the five purposively selected divisions of the city. The venues served as the primary sampling units for data collection and were selected with equal probability. New venues were added if the research assistant noticed other locations in the field that were not on the initial list. Second, at each of the selected venue, we applied respondent driven sampling (RDS) to recruit the eligible street children from their network groups for participation in the interviews. Since the numbers of the street children during the fixed time interval was small (15 or fewer), we interviewed all eligible street children found in the venue. RDS is a chain referral sampling method that produces a stable sample regardless of the make-up of initial recruits (Heckathorn 2002). In total, we enlisted a total 167 venues in 27 parishes selected from three of five city divisions. The identification of the locations and clients was made possible with the help of local urban leaders, service provider NGOs and/or street children landlords/caregivers. Venue-based time space sampling techniques are widely applied elsewhere to sample hidden populations for the purpose of collecting survey data(37).
Dependent variable
We created a binary composite variable “sexual and reproductive health (SRH) service use” from three dependent variables, namely: Use of contraception or family planning in lifetime; HIV testing in the past 12 months and sexually transmitted infections (STI) screening in the last 12 months preceding the survey. All the three variables were categorized into the binary outcome ‘Yes’ and ‘No’. Hence a participant who responded “yes” to either of the three questions was considered to have ever used SRH services: a) In the past 12 months, have you sought for STI testing/screening? (Yes/No); b) In the last 12 months, have you taken an HIV test and know your HIV status? (Yes/No); and c) Have you ever used any modern family planning in the last 12 months? (Yes/No); Positive responses to the above questions were further validated with follow-up questions on the type of SRH/family planning services utilized and STI symptoms experienced. A positive (“yes”) response to any one of these services was regarded as service utilization. Previous studies have used self-reports as a measure of health service utilisation and is thus deemed a reliable method(38)(39). In the final model, we report results for the composite variable, SRH use, as the main outcome variable.
Independent variables
The independent variables were selected based on the study conceptual framework as shown in figure 1. Rural-urban migration aspects measured include the following: place (district/region) of origin, duration of stay, residential mobility and number of return movements to the city. Specific questions included: In which district/region were you born?; Which year and month did you first come to arrive to settle in Kampala Capital city?; For how long have you stayed in Kampala capital city?; How many places have you stayed in since you first settled/arrived in the city?; In the past 24 months, have you returned to your home district/region of origin? (Yes/No). If yes, how many times did you go back to your place of birth/origin and returned to the city (round trips)? In this study, street children are defined as persons aged 12 to 24 years who migrated to and have stayed in Kampala city for period of not more than 24 months were classified as “migrant street children” while street children who had lived in the city for more than 24 months were considered “non-migrants or lifelong natives’. Children who had more than one repeat movements to their district of origin in the past 24 months preceding the survey were classified as “circular migrants”. Previous studies have used similar categorisations for migration status (40)(41). Other predictor variables include participant’s characteristics such as age, sex, marital status, schooling experience, education level, daily income and living arrangements, as demonstrated in the study framework.
Procedures
Between May and July 2019, data were collected using a pretested interviewer-administered semi-structured instrument programmed in English and two local languages, Luganda and Ngakarimajong, on mobile android PDA using CTO Survey tool. Luganda and Ngakarimajong are the most spoken languages by the street children. The electronic tool ensured minimisation of errors and completeness of interviews. Since the street children are connected through social networks, eligible respondents were recruited through respondent driven sampling in which street children had to lead the researcher to their peers for inclusion in the study. To ensure comprehension and high response rate, a team of 14 trained male and female research assistants who were fluent in both English and a local language conducted the interviews. All interviews took place in private spaces at the selected venues where street children congregate during the day. Written consent was obtained before interviews with the street children. A typical interview took less than 35 minutes. A venue was visited once, and all interviews were completed in 7 days. The principal investigator, biostatistician and study coordinator supervised the data collection process.
Data Analysis
To examine the effect of rural-urban migration aspects as the main independent variable and related predictors on the uptake of SRH services, we performed a stepwise binary logistic regression analysis using Stata version 16.00 version while controlling for confounding. All analyses were two-tailed, and a p-value of 0.05 or less was deemed statistically significant. Choice of variables in the final model was guided by the conceptual framework including assessing for multicollinearity among predictor variables. In all analyses, the levels of influence of the social ecological model were considered.