Table 2 Eligibility criteria for included articles

Participants

General population

Populations with specific conditions for breastfeeding or Code implementation (e.g., women living with HIV; orphaned or sick children who require special formula use).

Intervention

National laws imposing restrictions on the marketing of commercial milk formula (CMF), commercially produced complementary foods (CPCF), bottles, and teats following the scope of the Code, including:

1) CMF advertisement,

2) CMF promotions in public,

3) CMF promotions in health facilities,

4) Engagement between CMF companies and the health sector,

5) CMF labeling,

6) Promotion of CPCF, bottles, and teats.

National laws that regulate CMF products but are not specific to the Code, such as safety measures for CMF production and distribution, or ingredients requirement of CMF.

Comparators

Not applicable, as we aimed to summarize available evidence on national law implementation and thus included all study types primarily observational studies.

NA

Outcomes

The implementation outcomes of the national law adopted from the Code.

Other aspects that are relevant to the Code i.e. the Code’s history and interpretation, the formulation or adoption of the Code as national policy or law at the country level, or the progress of the Code implementation at the regional/global level

Settings

Any of 144 countries, as listed by WHO in 2022 [18], with national law adopted from the Code

50 countries, as listed by WHO in 2022, with no legal measures adopted from the Code.

Language

Published in English

Published in any other languages.

Year

Published from 1982, as the Code was first adopted in May 1981.

Published before 1982.

Publication

type

All study designs and publication types for which full texts were accessible.

Studies that did not include full texts (e.g., conference abstracts, posters), or for which they were unobtainable, or that did not include primary data collection (e.g. commentaries, editorials).