Prevalence and Patterns of Use of Natural Health Products and Medicines in New Zealand: A Pilot Study Using an Online Market Research Panel

Abstract

Background: Traditional, complementary and alternative medicine (TCAM), including natural health products (NHPs), are used by many consumers to address their [perceived] health needs. While many developed countries have national data on NHPs use, limited information is available for New Zealand (NZ). Current, robust data on the prevalence and patterns of NHPs use in NZ are required.

Objective: This project explored the feasibility of conducting a national study and collecting preliminary data on the prevalence and patterns of use of NHPs, including access to and expenditure on NHPs, and of the use of conventional medicines in NZ using a newly designed bespoke questionnaire.

Methods: An online cross-sectional survey was administered to a sample of the adult population in NZ via an online market research panel in November 2021. Self-reported data on participants' use of NHPs (including photographs of products), consultations with TCAM practitioners and use of conventional medicines were collected. Data on the prevalence and patterns of use of NHPs were analysed and reported using descriptive statistics. Multivariable logistic regression was applied to assess the impact of sociodemographic variables on NHPs, TCAM practitioners and conventional medicines use.

Results: The final sample comprised 992 participants. Sociodemographic data for these participants were comparable to those reported for the NZ Census 2018. The frequency of missing data was < 10% for most of the questions; data quality for broad-level prevalence analysis was good, but was moderate to poor for analysis at the specific NHP or TCAM practitioner level. The specific product(s) and their respective ingredient list(s) could not be determined for most NHPs described as photographs were not uploaded, rendering product names unverifiable. Preliminary data indicate that 57.6% of participants have used NHPs and 22.9% consulted a TCAM practitioner in the last 12 months. Among current NHP users, 71.1% concurrently used one or more conventional medicines. Over half (53%) of the NHPs were self-selected (not recommended by a health practitioner). The median daily cost per NHP was NZD 0.28 (interquartile range NZD 0.14-0.50) and the median cost for visits to a TCAM practitioner over the last 12 months was NZD 120 (interquartile range NZD 40-270). Female participants, younger individuals and conventional medicine users were more likely to use NHPs/consult a TCAM practitioner/use any TCAM. Higher-income participants were more inclined to consult a TCAM practitioner. Individuals born overseas were more likely to use any type of TCAM.

Conclusions: There was a high prevalence of use of NHPs and of consultations with TCAM practitioners, which may reflect the extent of use in the general NZ population. Recognising the potential impact on patients' health outcomes, there is a need for a larger and nationally representative dataset, preferably linkable to other health data collections, to validate these preliminary findings.

Fig. 1

Questionnaire distribution and response rates

Fig. 2

Overview of the data quality of the market research dataset. NHP natural health products, OTC over-the-counter medicines, TCAM traditional, complementary and alternative medicines. Box fill colour indicates data quality, orange: poor, yellow: moderate, green: good. Data quality rated based on missing data and any anomalies (e.g. misinterpretation of questions). ^aMissing data < 5%. ^bMissing data 5–10%. ^cMissing data 10–20%. ^dMissing data > 20%. ^eMissing data/question < 10% except for cost-related (~ 13.4%) and photograph (76.4%) questions. Most entries were not formulated/specially compounded products and the data were inadequate to identify a specific product/preparation. ^fMissing data/question < 10% except for questions related to cost (~ 10%), photographs (~ 66%), brand/manufacturer names (12.7%), ingredients (10.5%), and barcode (58.5%). ^gMissing data/question < 10% except for questions related to cost (~ 17%), photographs (~ 78%), brand/manufacturer names (17.1%), ingredients (10%), and barcode (84.3%). Most entries were manufactured products (64.3%) and only 15 entries (21.4%) had photographs. ^hMissing data/question < 5%, except for question related to cost (8.3%). ⁱMissing data/question < 1%, except for question on brand/manufacturer name (15.8%). Medicine unidentifiable for 5.9% of entries due to errors (e.g. inadequate and/or irreconcilable information, non-conventional medicines). ^jMissing data/question <5%, except for question on brand/manufacturer name (8.3%). Medicine unidentifiable for 15.5% of entries due to errors (e.g. inadequate and/or irreconcilable information, non-conventional medicines). ^kMissing data/question <5%, except for question on brand/manufacturer name (14.4%). Medicine unidentifiable for 15.5% of entries because of errors (e.g. inadequate and/or irreconcilable information, non-conventional medicines). ^lIngredients data unreliable, except where photographs are available for verification. ^ySubstantial number of products were incorrectly categorised as ‘formulated’. ^zQuestions were misinterpreted