Clinical evaluation of traditional medicine The examples of "Yoga for stress reduction" and "Outpatient use of cannabis-based medicines in Germany"

Evaluating traditional medicines based on the criteria of evidence-based medicine offers the opportunity to identify readily available and cost-effective therapies. Despite decades of international efforts, there is still a great need for research in this area. In addition to economic reasons, there are methodological challenges. The often complex mechanisms of action of traditional medicines can make it difficult to define clinically relevant study endpoints, control groups and study populations. This requires an understanding of the reasons for their application and also of the subjective experience of their application. Qualitative research methods can be used to gain these insights. The following section describes how this has been implemented in specific cases. In the so-called RELAX study, three methods of stress reduction were compared in a three-armed, randomized controlled trail in n=102 healthy adults suffering from stress and stress-associated secondary diseases. The examined methods of integrative yoga, Iyengar yoga and mindfulness training were equally effective. There were no significant group differences in the primary variables and only marginal differences in the secondary variables. It was concluded that all three methods can be used in practice according to patient preference and availability. Qualitative interviews showed that the amount of time consciously spent on relaxation was considered particularly relevant. This led to the new hypothesis that readily available and less expensive alternatives could be similarly effec- tive as the relaxation methods studied. In the so-called EXCARP study, a survey of the hard-to-reach study population of patients who were being treated with cannabis-based medication on an outpatient basis was conducted. The study design was intended to enable a representative survey by means of a stratified cluster sample. Whether this was successful is uncertain. Qualitative interviews were conducted to understand the subjective treatment experiences. Special attention was paid to quality of life and mental illness as a result. 11,744 physicians were contacted to reach n=216 patients. There were significant improvements in almost all examined variables. In particular, quality of life and pain improved significantly. The sur- vey included a large proportion of privately insured patients (16%) and a large proportion of patients receiving treatment with cannabis flowers (45%). This is a relevant coverage of patient groups that have so far been underrepresented. The study results contribute to a better description of the population of outpatient cannabinoid patients in Germany and point to the known efficacy of cannabis-based med- ications for some indications. The studies presented thus contribute to level III evidence for the outpatient use of cannabinoids and to level 1b evidence for yoga, Iyengar yoga, and mindfulness training for stress reduction.