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A pilot study found no significant difference in hair cortisol or cortisone between circumcised and intact men. However, the study was underpowered, and its conclusions about circumcision

Keywords:
PTSDcircumcisionnegative resultsnull-hypothesis significance testingunderpowered studies

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Area of Science:

  • Endocrinology
  • Psychiatry
  • Urology

Background:

  • Male circumcision is a common procedure with ongoing debate regarding potential long-term psychological effects.
  • The hypothalamic-pituitary-adrenal (HPA) axis is a key regulator of the stress response.
  • Hair cortisol and cortisone levels are increasingly used as biomarkers for long-term stress exposure.

Purpose of the Study:

  • To investigate potential long-term psychopathological effects of male circumcision by examining hair cortisol and cortisone levels.
  • To assess the functionality of the HPA axis in circumcised versus non-circumcised men.

Main Methods:

  • A pilot study comparing hair cortisol and cortisone levels in circumcised men and genitally intact (non-circumcised) men.
  • Analysis of hair samples to measure levels of cortisol and cortisone, serving as biomarkers for chronic stress.
  • Statistical analysis to determine significant differences between the two groups.

Main Results:

  • The study reported no statistically significant reduction in hair cortisol or cortisone levels in circumcised men compared to non-circumcised men.
  • The authors interpreted these null findings as evidence against long-term psychopathological effects of circumcision.
  • The authors also claimed evidence for healthy HPA axis functionality in circumcised individuals.

Conclusions:

  • The authors' conclusions regarding the refutation of psychopathological effects and healthy HPA axis functionality are not supported by the null findings of this underpowered pilot study.
  • The study's limitations, including potential underpowering, suggest that the observed trends might indicate opposite effects in a larger, adequately powered study.
  • Weaknesses in study design, measurement, and interpretation further undermine the authors' strong claims, indicating their conclusions are not data-supported.