Socio-economic and demographic characteristics of audit cohort
| Characteristic | Proportions in cohort |
| Age | |
| 16–19 years | 4.6% |
| 20–30 years | 45.6% |
| 31–44 years | 49.8% |
| Country of birth classification Using World Bank economies list (www.worldbank.org/data/countryclass/classgroups.htm) | |
| Low income country | 20.4% |
| Lower middle income country | 10.3% |
| Upper middle income country | 4.5% |
| High income country (including the UK) | 57.7% |
| Socio economic status | |
| Using Index of Multiple Deprivation (IMD) scores based on postcode of residence ranked within cohort from ‘most deprived’ to ‘least deprived’ | Grouped in quintiles |