Men with subjective premature ejaculation have a similar lognormal IELT distribution as men in the general male population and differ mathematically from males with lifelong premature ejaculation after an IELT of 1.5 minutes (Part 2)

Int J Impot Res. 2019 Sep;31(5):341-347. doi: 10.1038/s41443-019-0172-5. Epub 2019 Aug 8.

Abstract

Men with Subjective premature ejaculation (PE) have complaints of PE but have normal intravaginal ejaculation latency time (IELT) durations. We found two previously published large epidemiological stopwatch-mediated IELT studies to encompass IELT details of men with Subjective PE, albeit this term was not mentioned in both studies or in reviews of them. In the current study we developed the mathematical formula of the IELT distribution of men with complaints of PE, as diagnosed by a clinician on basis of the DSM-IV-TR definition of PE, as reported in the two studies performed in the USA and Europe, respectively. The formula was calculated by investigation of the fitness of various well-known mathematical Probability Density distributions into the IELT distribution of the PE men and non-PE men of the two studies. The better the fitness the lower is the Goodnes of Fit (GOF). Another aim of the study was to investigate whether the IELT distribution of men with "complaints" of PE (Subjective PE) differs mathematically from the IELT distribution of the general male population and that of Lifelong PE. The overlap of the area under the curve (AUC) of the IELT distribution of the men with PE complaints and that of the general male population was calculated together with the cut-off point at which the AUC equals 10%. We found that the IELT distributions of the PE men in both studies were Lognormal distributions and that at the cut-off point at which the AUC is equal to 10% (p = 0.10) the IELT is 1.5 min, indicating that after 1.5 min the IELT distribution of males with complaints of PE becomes mathematically identical to that of the general male population. In conclusion, there is hard mathematical evidence that the IELT distribution of men with complaints of PE with normal IELT values (e.g., the Lognormal IELT distribution of Subjective PE) and the IELT distribution of men with Lifelong PE (e.g. the Gumbel Max IELT distribution) belong to two independent populations. According to the applied mathematical calculations Subjective PE starts after an IELT of 1.5 min and encompasses all higher IELT values. It may imply that the current IELT cut-off point in Lifelong PE should be 1.5 min instead of the approximate 1 min, as has previously been stated by ISSM and DSM 5.

MeSH terms

  • Europe / epidemiology
  • Female
  • Humans
  • Male
  • Premature Ejaculation / diagnosis
  • Premature Ejaculation / epidemiology*
  • Premature Ejaculation / psychology
  • United States / epidemiology