Siemens CLINITEST - Home Test23 Apr 2021 23:54
Another puzzling one and an example of misleading performance data and use case. Sorry for the long read.
This test has recently received certification for home use in Germany following a 50 person lay study, having already held a CE mark for pro use.
https://www.corporate.siemens-healthineers.com/press/releases/covid19-self-test
Intended Use
“ The CLINITEST® Rapid COVID-19 Antigen Test is an in vitro immunochromatographic assay for the qualitative detection of nucleocapsid protein antigen from SARS-CoV-2 in direct nasopharyngeal (NP) swab or nasal swab specimens directly from individuals who are suspected of COVID-19 by their healthcare provider. It is intended to aid in the rapid diagnosis of SARS-CoV-2 infections and can be used by healthcare professionals up to ten days post symptom onset, or to screen asymptomatic individuals or individuals from areas of low infection prevalence. Negative results from patients with symptom onset beyond ten days should be treated as presumptive and confirmation with a molecular assay, if necessary, for patient management, may be performed. The CLINITEST Rapid COVID-19 Antigen Test does not differentiate between SARS-CoV and SARS-CoV-2. The test also provides individuals with the option to self-collect their nasal sample under the supervision of a healthcare professional.”
Summary;
Sample - NP or AN
Symptomatic or Asymptomatic
Results in 15 mins
N protein targeting.
AN Sens: 97.25%
AN Spec: 100%
https://cdn0.scrvt.com/39b415fb07de4d9656c7b516d8e2d907/aef3862a159f8063/80b57fc93ae3/CLINITEST-Rapid-COVID-19-Antigen-Test-PI-Healgen-CE-Rev.-G_English.pdf
First glance - superb. But scratch the surface...
It appears to be yet another NP designed test to detect symptom onset individuals, repurposed as an asymptomatic AN test. Ala Innova.
My conclusion was drawn from this study:
https://www.medrxiv.org/content/10.1101/2021.02.02.21250984v1.full-text
Which evaluates and presents the data in a simple to read, no smoke a mirrors style, Ct value metrics, etc. And...It concludes:
Sens (Symptomatic): 80.2%
Sens (Asymptomatic): 60%
Adding: “ In contrast, the POC performance of this and other RAD assays [1,6], is clearly suboptimal in asymptomatic close-contact individuals, either household or non-household. This was also observed in a previous study using the Panbio RAD assay from Abbott Laboratories“.
In conclusion - it is very bad at detecting asymptomatic individuals and not fit for purpose.
There are so many inconsistencies with tests currently on the market, especially those reacting quickly to the demands of it. AS provided an honest no holds barred view of our test performance. The performance in all areas is first class.