Regarding the Robustness of Results for “Association of Tryptophan Metabolites with Incident Type 2 Diabetes in the PREDIMED Trial: A Case–Cohort Study”

Ultra hCG device capable of detecting physiologically relevant concentrations of hCG␤cf, ultimately reducing the likelihood of false-negative results.However, it is disturbing that the other 2 OSOM devices (OSOM Combo and OSOM Card) are still marketed for use.The package inserts of the OSOM Combo and OSOM Card devices state: "This assay is capable of detecting only whole molecule (intact) hCG, which is the predominant form of hCG in early pregnancy.It cannot detect the presence of hCG fragments or free subunits.In later term pregnancies (generally beyond the first trimester), occasionally urine samples can contain very high levels of hCG fragments.Therefore, the OSOM Pregnancy test is most effective when used for the detection of pregnancy in earlier stages."However, concentrations of hCG␤cf are known to be increased as early as week 7 of pregnancy (3 ), and there is no warning about the potential for false-negative results because of high hCG␤cf, only that these fragments will not be detected.We applaud the manufacturer for the addition of the OSOM Ultra device to its menu.However, we urge the manufacturer to either remove the other devices from the market or include cautionary information about the potential for false-negative results in women beyond 7 weeks of gestation.