---
title: "Blinded experiment"
chunk: 3/3
source: "https://en.wikipedia.org/wiki/Blinded_experiment"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T03:43:16.884871+00:00"
instance: "kb-cron"
---

==== Acupuncture ====
While the possibility of blinded trials on acupuncture is controversial, a 2003 review of 47 randomized controlled trials found no fewer than four methods of blinding patients to acupuncture treatment: 1) superficial needling of true acupuncture points, 2) use of acupuncture points which are not indicated for the condition being treated, 3) insertion of needles outside of true acupuncture points, and 4) the use of placebo needles which are designed not to penetrate the skin. The authors concluded that there was "no clear association between the type of sham intervention used and the results of the trials."
A 2018 study on acupuncture, which used needles that did not penetrate the skin as a sham treatment, found that 68% of patients and 83% of acupuncturists correctly identified their group allocation. The authors concluded that blinding had failed, but that more advanced placebos may someday enable well-blinded studies in acupuncture.

=== In physics ===
It is standard practice in physics to perform blinded data analysis. Once the data analysis is complete, one may unblind the data. A prior agreement to publish the data regardless of the results of the study may be made to prevent publication bias.

=== In social sciences ===
Social science research is particularly prone to observer bias, so it is essential in these fields to properly blind the researchers. In some cases, while blind experiments would be helpful, they are impractical or unethical. Blinded data analysis can reduce bias, but is rarely used in social science research.

=== In forensics ===
In a police photo lineup, an officer shows a group of photos to a witness and asks the witness to identify the individual who committed the crime. Since the officer is typically aware of who the suspect is, they may (subconsciously or consciously) influence the witness to choose the individual that they believe committed the crime. There is a growing movement in law enforcement toward a blind procedure in which the officer who shows the photos to the witness does not know the suspect's identity.

=== In music ===

Auditions for symphony orchestras take place behind a curtain so that the judges cannot see the performer. Blinding the judges to the gender of the performers has been shown to increase the hiring of women. Blind tests can also be used to compare the quality of musical instruments.

== See also ==

Allocation concealment
Amplified placebo effect
Black boxing
Blind taste test
Inverse placebo effect
Jadad scale
Lessebo effect
Observational study
Metascience
Royal Commission on Animal Magnetism
Scientific control

== References ==