The physicians of topical innovations have developed at their center in the Netherlands, patients a new placebo controlled test paradigm. In order to identify putative responders and exclude an (initial) placebo-response, first a single-blind and subsequently a double-blind placebo-controlled response tests has been developed.
This test can be performed when the patient has a symmetrical polyneuropathy with a pain score difference of not more than 1 point on the 11-point numerical rating scale (NRS) between bilateral pain areas. On one area (eg, left foot) the placebo cream and on the other area (eg, right foot) the active cream will be applied. Within a time frame of 30 minutes, patients are considered responders if they rate a pain difference of at least 2 points on the NRS between the bilateral areas on which the active cream and placebo cream are applied. Response tests can be easily conducted during the first consultation.
In the January 2019 paper in the Journal of Pain research, the authors present for the first time the ethical context of using a placebo in clinical practice in a single-blind and double-blind fashion to improve and individualize treatment of neuropathic pain outside a context of a formal clinical trial.
Keppel Hesselink JM, Kopsky DJ, Bhaskar AK. Ethical justification of single-blind and doubleblind placebo-controlled response tests in neuropathic pain and N-of-1 treatment paradigm in clinical settings. J. Pain Res. 2019; 12: 345–352. (PDF)