History of Rural-to-Urban migration within low-and-middle-income country (LMIC)

Children under the age of 5 years

Non-migrants (rural and urban), rural–rural migrants

Studies in which migrants’ origin is not rural (eg, urban–rural, urban–urban migrants)

Studies with no mention of migration status or the migration status is unclear

Quantitative coverage of any/all of the WHO recommended routine vaccines under the original Expanded Programme on Immunisation (EPI). These are: BCG, diphtheria-tetanus-pertussis, oral polio, measles and recently added hepatitis B and Haemophilus influenzae type B vaccines. As well vaccines relevant to country-specific EPI schedule.

Immunisation status assessed objectively using child's immunisation records or health facility data and maternal/care-giver recall

Quantitative coverage of non-routine EPI vaccines

Supplementary immunisation activities (SIAs) and campaigns

Studies assessing Immunity to VPDs

Observational studies

Any publication date

Any language

Published and unpublished data

Qualitative studies

Policy papers without original data