Our solution
To better understand the context in The Gambia and to support the definition of The Gambia Education and Training Project Concept, MCC requested SBC4D to map and analyze the current state of secondary school digital readiness, including internet connectivity and electricity access in the country. Additionally, MCC requested an overview of potential digital resources, tools and technologies that might be feasible to introduce in secondary schools, given electricity and internet accessibility realities in The Gambia. Whythawk was contracted to provide technical statistical support to this process.
A rapid review of the literature was conducted to inform the design of a survey instrument to be deployed in a national survey of a representative sample of government and grant-aided secondary schools in The Gambia. The results of the survey will, in turn, provide an empirical basis from which to evaluate the feasibility of implementing the digital solutions implemented elsewhere in The Gambia (or other countries with comparable contexts), and to make recommendations for interventions in The Gambia’s secondary-school system.
There are 811 secondary schools in The Gambia. The survey population consists of only the 380 government- and grant-aided secondary schools (i.e. it excludes private schools and madrasas).
Sample selection for small population sizes is different from the predicted standard formulae used in more general sampling. Cochran’s formula (as example, used in many online calculators), takes as an assumption an “infinite” population size. However, our population differs.
- Our population is small and of unknown heterogeneity. We know they’re all schools with a similar objective, but the way they are run, staffed, operated, and resourced can make them very much unlike each other, with a high probability of outliers. At the same time, our objective isn’t ensuring inclusion of these outliers. It is not a clinical trial where a large sample size is needed to ensure inclusion of the rare event (e.g. a medical condition to be studied), but closer to a survey, where what is needed is to understand a typical range of conditions so that an appropriate intervention can be formulated.
- However, we do know a range of criteria for these schools (size, teacher/student ratio, educational outcomes), and so when we sample we can test the correspondence of the sample to the distribution of these known criteria. This means, even if we don’t know the heterogeneity, we can be certain that the sample represents the population as a whole.
At small population size, we can use the methods presented by Hoyle during this workshop on improving health research for small populations. Our objective is appropriate statistical power, along with a calibrated sample size. For this type of population and study, power of 80% is appropriate.
Two types of survey instruments were developed: (1) questionnaires and (2) an observational checklist. The design of the survey instruments was informed by two previously-completed pieces of research: (1) The data ecosystem assessment and (2) the rapid literature review. These documents identified key areas of relevance for which data are required to inform future decisions about the most feasible and effective digital interventions for secondary schools in The Gambia.
Outcomes
Whythawk successfully completed technical support for the survey, including complex analysis for statistical rigor. The project was intended to be continuous with implementation after the conclusion of the survey, but the project was abruptly ended after the destruction of USAID-funded initiatives, including the MCC.
