Lay summary
Many people in New Zealand use ‘natural health products’/complementary medicines (NHPs) and 'traditional medicines' (NHPs/TMs) for health and wellbeing. Some people use NHPs/TMs with other complementary therapies or conventional medicines. New Zealand does not have reliable information on how many people use NHPs/TMs, how people use them with other therapies and medicines, and on how much people spend on these healthcare approaches. It is important to have this information so that we can look at trends in how people use, access, and pay for these healthcare approaches. This study involves developing a questionnaire to collect information on peoples' use of all types of medicines, including NHPs/TMs and conventional medicines, as well as complementary therapies. We also need to test the questionnaire to check that it collects the information we need. This work will lead to a bigger, future study – an NHPs and medicines census – for all New Zealanders.