CAMbrella Final Report

Work package 4:

CAM use – the patients' perspective

Leading beneficiary: University of Southampton (US)

The objectives of WP4 were to:

  • address the prevalence of CAM use in Europe, taking into account regional and national variations, and creating a summary of current information about prevalence of CAM use and its trajectory
  • identify the major conditions treated with CAM, based on existing literature as well as suggesting future research strategy to overcome relevant evidence gaps
  • explore the reasons why patients choose CAM through a systematic review of survey material and existing databases
  • identify a standardised questionnaire for CAM use in at least 3 European languages that will provide a consistent EU approach to a widespread, but clearly defined range of CAM.

Description of work:
First, WP4 used a developed systematic review protocol in order to perform the original literature searches, so as to evaluate the use of CAM by EU citizens. Over 5,500 papers were identified in the peer-reviewed literature. After removing duplicates and excluded opinion pieces, editorials or letters, guidelines, reviews, pharmacological, historical or geographical studies, effectiveness or efficacy studies and ethno botanical research, qualitative studies pertaining to the attitudes of CAM patients, CAM practitioners or CAM education and any studies of CAM use in disease specific populations, a total of 190 papers left potentially containing CAM use prevalence in general population surveys. Full papers were retriever from the publishing journals, and further papers were excluded that did not meet the inclusion criteria. In the end 87 eligible studies were included in the final analysis. This selection process resulted in the fact that for 25 EU member states (64%) no general population data on CAM use was located. The main characteristics of the included studies were that:
a) the studies were generally of poor quality,
b) in 32% of the papers, CAM was not defined to survey participants, and
c) only 29% reported pilot studies of the questionnaire used and 79% reported data collection strategies that were subject to recall bias (recall over 12 months or more).
Second, a standardised European Questionnaire (I-CAM-Q)80 was translated from English into German, Italian, Spanish, Hungarian, Romanian and Dutch. Country specific instructions were added as some terms differ across countries, e.g. the term chiropractor does not exist in Romania and would be poorly understood. It was also noted that there were differences in provider qualifications between countries, and with respect to education (MD or non MD). The translation of terms with explanations was also used on a country specific basis. A protocol was developed to perform a pilot-study with 50 people (40 people completed the questionnaire alone and returned it by post, and 10 completed it with a researcher).

There is a lack of reliable data on the prevalence of CAM. However, use of herbal medicine was the most frequently reported use of CAM. Musculoskeletal problems were the most reported condition (Eardley S et al. A systematic literature review of Complementary and Alternative Medicine prevalence in EU. Forsch Komplementmed 2012;19(suppl 2):18-28)81. While there are a few rigorous prevalence studies that are based on nationally representative samples, the vast majority are small and of poor quality. Most EU countries do not have any data at all. Reported prevalence rates of CAM use were between 0.3% and 86%. We were unable to calculate the overall prevalence rate for herbal medicine, homoeopathy, chiropractic, acupuncture or reflexology by either country or across the EU or to differentiate between practitioner (doctor) based prescriptions and over the counter purchases of homeopathic and herbal medicines.

Prevalence rates of the main therapies in use were reported as follows:

  • Herbal medicine (31 studies): prevalence rates varied from 5.9 - 48.3% of the population studies. However herbal medicine was not well defined (it may be included in naturopathy, folk medicine or traditional Chinese medicine) and variously categorised as medical herbalism, herbal remedies, herbal teas, phytotherapy. Some specific herbs were reported by name such as St John’s Wort.
  • Homeopathy (25 studies): prevalence rates varied from 2 - 27% of the populations studied.
  • Chiropractic (17 studies): sometimes reported as ‘Chiropractic or osteopathy’ (1 study), as one of a group of CAMs (4 studies) and as ‘manual or manipulative treatments’ (2 studies. Prevalence rates were 0.4 - 20.8% of the populations studied. 
  • Acupuncture (14 studies): was poorly defined. Prevalence rates were 0.44 - 23% of the populations studied. Eight further studies reported acupuncture as part of groups of CAMs.
  • Reflexology (11 studies): and in a group of CAMs in one other study. Prevalence rates varied from 0.4 - 21% of the populations studied.
  • Dietary supplements: calcium supplement use was reported in 9 studies. Use of all other dietary supplements, vitamins, minerals, fish oils, glucosamine and other products was reported heterogeneously in groups, singly or combinations of supplements in 28 papers. It was not possible to distinguish whether the dietary supplements were bought over the counter or prescribed at consultations.

As regards a reliable method to measure CAM prevalence the analysis of the pilot study identified common problems across countries including a ‘hard to read’ layout, misunderstood terminology and uncertainty in choosing response options. Quantitative analysis confirmed that a substantial minority of respondents failed to follow questionnaire instructions and some questions had substantial rates of missing data. As a self-complete questionnaire, there were serious indications that I-CAM-Q has low face validity, low acceptability, and is likely to produce biased estimates of CAM use if used in England, Romania, Italy, Netherlands or Spain. There is need for major revision before it can be widely utilized for this purpose (Eardley et al. A pilot feasibility study of a Questionnaire to determine European Union-wide CAM use. Forsch Komplementmed 2012;19:302-310). (82)