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Updated: Jul 20, 2026

Assessment of Sexual Behavior of Male Mice
Published on: March 5, 2020
Evaluation of the Sexual Assessment Monitor, a diagnostic device used to electronically quantify ejaculatory latency
Wallace W Dinsmore1, David J Ralph, Phillip Kell
1Royal Victoria Hospital, Belfast.
Objective:
To validate the Sexual Assessment Monitor (SAM), a novel apparatus designed to collect electronic data on ejaculatory latency time (ELT) for diagnosing premature ejaculation (PE), and for accurately measuring treatment outcomes in clinical trials.
Patients, Subjects And Methods:
Men with PE, and healthy volunteers aged 18-75 years, were enrolled in three open-label studies, conducted in the UK. The SAM, which consists of a control box with two front attachments, a vibrator and sensor, was attached to the penis. The vibrator, which provides stimulation, was positioned at the frenulum using a soft cuff; the vibrator intensity was set at 80 units for most subjects. The sensor is an indium-gallium elasticated loop, which was positioned around the base of the penis to detect ejaculatory pulses. These pulses were transmitted to a data recorder in the control box. The data, which are displayed graphically as traces, were automatically classified by a computer-generated algorithm to quantify ELT.
Results:
In all, 53 healthy volunteers and 58 men with PE provided 213 and 195 evaluable records, respectively. Most were complete records (99% and 96%). The pooled data showed that the ELT was much higher for healthy volunteers than for men with PE (geometric means: 687 vs 169 s, respectively), with a healthy volunteer to PE patient ratio of 2.87 (P < 0.001). Only 6.3% of subjects reported mild adverse events, which were unrelated to the SAM.
Conclusions:
These open-label studies show that the SAM can consistently and safely measure times to erection (from the start of vibration) and ejaculation, and ELT in healthy volunteers and men with PE. These findings show that the SAM has the potential to become the 'gold standard' in the diagnosis of PE and in clinical trials design.

