Treatment Recommendations Should Take Account of Individual Patient Variation Not Just Group Responses
Recommendations for treatment are commonly based on results evaluating variation in systematic effects (group responses) from randomised controlled trials without taking the individual patient's variation into account. In the evaluation of acupuncture-related treatment effects, the trial design and statistical analysis used are a challenge since the assessed variables commonly have subjective properties and are based on the person's own self-report. Thus, the results that are seen are often varied, most likely due to inter-individual variation in rating of the actual variable such that the treatment effects are expressed more (or less) in some individuals than in others. The basis for the individual variation is probably multi-modal and could be related to the individuals’ expectation, gender, genetic polymorphisms and the aetiology of the condition. The assessment methods used should preferably have proven useful in controlled trials, and the methods for statistical analysis should consider the non-metric properties of the variable and the contribution of the individuals’ variation in the results. In order to evaluate the treatment effects more properly and increase the possibility of detecting any effectiveness, it is therefore important to assess the level of perceived dysfunction or symptom, taking into account the individual variation as well as the systematic effects (the effects of the group). In the evaluation of acupuncture effects, both systematic and individual variation should be reported allowing for the detection of subgroup effects and thereby leading to treatment recommendations that are more likely to be based on each individual's specific needs.