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Tap Water Placebo Developed and Validated for Medicinal Water Efficacy Trials

4 years ago3 min read

Key Insights

  • Researchers have developed and validated a method to create a placebo from tap water for use in medicinal water efficacy trials, addressing a critical need in balneotherapy research.

  • The study involved 174 patients and found no significant differences in perception between those treated with medicinal water and those treated with the tap water placebo.

  • This validated placebo method enables more rigorous, placebo-controlled randomized clinical trials to assess the true benefits of medicinal waters, such as Harkány medicinal water.

Researchers have successfully developed and validated a method for producing a placebo from tap water, intended for use in medicinal water efficacy trials. This advancement addresses a significant challenge in balneotherapy research, where the creation of an indistinguishable placebo has been difficult. The study, conducted at the Harkány Spa Hospital in Hungary, aimed to create a cost-effective and easy-to-use placebo for Harkány medicinal water.
The study enrolled 174 patients, dividing them into two groups: one receiving Harkány medicinal water and the other receiving the tap water placebo. Participants underwent a single 20-minute treatment in bathtubs and were asked to identify the water type four times during the session. The results indicated no significant differences between the average scores or answers of the two groups, confirming the tap water effectively served as a placebo. The study was a randomised (1:1 for two groups) triple-blind, controlled, parallel-group study conducted at the Harkány Spa Hospital

Overcoming Challenges in Balneotherapy Research

Medicinal waters have been used for therapeutic purposes for centuries, particularly for musculoskeletal, dermatological, and gynecological conditions. However, a lack of proper placebo-controlled randomized clinical trials (RCTs) has hindered the recognition and financial support of balneotherapy in some countries. The primary challenge lies in producing a placebo that mimics the characteristics of medicinal water, including scent, color, and sensation.
Previous studies have often used tap water as a placebo without validating whether patients could distinguish it from medicinal water. This new method, validated through rigorous testing, ensures that patients cannot differentiate between the medicinal water and the tap water placebo, thereby strengthening the integrity of clinical trials.

Methodology and Findings

The method involved coloring both the Harkány medicinal water and tap water with commercially available water coloring tablets to ensure visual similarity. The pH of the tap water was adjusted to match that of the medicinal water. Patients were asked to identify the water type at various points during the treatment, and their responses were scored. Statistical analysis revealed no significant differences in the scores between the two groups (p=0.128), indicating successful blinding.
Notably, being familiar with Harkány medicinal water did not influence the rate of correct answers, further supporting the effectiveness of the placebo. The study also assessed the number of changes in opinions during the questioning, finding no statistically significant difference between the two groups (p=0.199).

Implications for Future Research

This validated placebo method represents a crucial step forward in evidence-based balneology research. By providing a reliable placebo, researchers can now conduct more rigorous RCTs to determine the true benefits of medicinal waters. This is particularly important for Harkány medicinal water, which contains carbonyl sulfide (COS) and is used to treat degenerative joint and spinal disorders.
"Based on our findings, our opinion is that a placebo validation should be the first step before performing a randomized, controlled, double-blind clinical trial in balneotherapy research," the researchers stated. The limitation of this trial is that this method is appropriate to produce placebo water only for Harkány medicinal water.
The development of this tap water placebo could pave the way for more widespread acceptance and utilization of balneotherapy as a legitimate treatment modality.
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