Table 1 Overview of data collection phases, steps, sources and instruments

1: Identifying interventions

1: Searching existing sources

Sources: Databases, abstract books, internet

2: Identifying and approaching key informants

Sources: Researchers’ professional networks, EU projects, public health networks, government departments, non-governmental organisations. Instrument: Short questionnaire (Additional file 1)

3: Identifying contact persons of interventions, collecting general information on interventions

Sources: Key informants, internet

2: Collecting and verifying detailed information

1: Selecting interventions

Instrument: Research team analysis of short questionnaire and other available information

2: Collecting detailed information on interventions

Instrument: Partially pre-filled extensive questionnaire (Additional file 1)