Novel centrifugal technology for measuring sperm concentration in the home

Trak is declared a ‘novel technology for measuring sperm concentration at home’. This study recorded results from self-testing users and the laboratory reference method and were evaluated against Trak’s semiquantitative method of measurement. See Fertility and Sterility for full text.

Objective
To evaluate the analytical performance and usability of the Trak Male Fertility Testing System, a semiquantitative (categorical) device recently US Food and Drug Administration (FDA)-cleared for measuring sperm concentration in the home by untrained users.

Design
A three-site clinical trial comparing self-reported lay user results versus reference results obtained by computer-aided semen analysis (CASA).

Setting
Simulated home use environments at fertility centers and urologist offices.

Patient(s)
A total of 239 untrained users.

Figure 1
The Trak Male Fertility Testing System. (A) Photo of the system contents, including the reusable Engine,
fluid transfer device, instructions, liquefaction cups, seal-before-spin stickers, the Prop in a foil pouch, and several unpouched Props. Photo shows a Prop placed on the Engine with a seal-before-spin sticker in place. (B) Photo of the Prop, with and without label. (C) Example test results of semen samples with low (≤15 M/mL), moderate (15–55 M/mL), and optimal (>55 M/mL) sperm concentrations.

Main Outcome Measure(s)
Sperm concentration results reported from self-testing lay users and laboratory reference method by CASA were evaluated semiquantitatively against the device’s clinical cutoffs of 15 M/mL (current World Health Organization cutoff) and 55 M/mL (associated with faster time to pregnancy). Additional reported metrics include assay linearity, precision, limit of detection, and ease-of-use ratings from lay users.

Figure 2
Linear assessment. A Deming regression best-fit line is also plotted for reference (slope = 0.91, intercept = 2.0 M/mL), along with 95% confidence interval (CI) estimates for the Deming best-fit line. r = 0.99.

Result(s)
Lay users achieved an accuracy (versus the reference) of 93.3% (95% confidence interval [CI] 84.1%–97.4%) for results categorized as ≤15 M/mL, 82.4% (95% CI 73.3%–88.9%) for results categorized as 15–55 M/mL, and 95.5% (95% CI 88.9%–98.2%) for results categorized as >55 M/mL. When measured quantitatively, Trak results had a strong linear correlation with CASA measurements (r = 0.99). The precision and limit of detection studies show that the device has adequate reproducibility and detection range for home use. Subjects generally rated the device as easy to use.

Conclusion(s)
The Trak System is an accurate tool for semiquantitatively measuring sperm concentration in the home. The system may enable screening and longitudinal assessment of sperm concentration at home.

Authors
Ulrich Y. Schaff, Ph.D., Laura L. Fredriksen, M.S., Jon G. Epperson, B.S., Tiffany R. Quebral, B.A., Sara Naab, M.S.I., Mark J. Sarno, E.J.D., Michael L. Eisenberg, M.D., Greg J. Sommer, Ph.D.

February 2017 Volume 107, Issue 2, Pages 358-364. e4