Section 1B: UK Immigration Policy and Migration
Datasets and Preprocessing
Two datasets were used to examine the relationship between UK immigration policy and the migration of Nigerian healthcare workers. The first dataset captured UK immigration policy changes and was used to construct a cumulative Policy Index, where lower values indicate more restrictive policy conditions. The second dataset contained migration totals of Nigerian healthcare workers to the United Kingdom for selected years (2000, 2005, 2010, 2015, 2020, and 2024).
Both datasets were structured using year as a common variable, allowing them to be merged into a single dataset for analysis. The final dataset included three variables: year, Policy Index, and healthcare migration.
Before analysis, the data were standardised to ensure comparability. This included aligning time periods across both datasets and transforming variables where necessary for correlation and regression analysis. Standardisation also enabled clearer interpretation of trends and relationships between policy and migration over time.
Analytical Approach
A quantitative analytical approach was adopted to assess the relationship between UK immigration policy and Nigerian healthcare worker migration.
The analysis was conducted in four stages. First, the Policy Index was plotted over time to examine changes in immigration policy openness. Second, migration trends were visualised alongside the Policy Index to identify patterns and potential relationships.
Third, both variables were standardised and a Pearson correlation analysis was conducted to measure the strength and direction of the relationship between policy and migration.
Finally, an Ordinary Least Squares (OLS) regression model was estimated to quantify the association between the Policy Index (independent variable) and healthcare migration (dependent variable). The model is expressed as:
HealthcareMigration =β0 +β1 (PolicyIndex)+ε
This approach allows for the estimation of how changes in immigration policy are statistically associated with changes in migration levels.
| ← Previous: Section 1A | Next: Section 2 → |