The Science

Reportable ranges

Every analyte Clinicore reports by LC-MS/MS, with the interval it reports over. Published openly so an ordering physician can decide whether the assay fits their clinical question before they order it, rather than after.

These are not the instrument's detection floor

Each limit is set at a concentration the method reproduces reliably under production conditions — at a throughput of 120 samples per day per instrument, not in a best-case sensitivity study with a technologist watching.

Clinicore's sensitivity studies demonstrate performance below these limits. We publish the concentration we can deliver every day rather than the one we achieved once.

The distinction is real, and it is why clinicians are right to be sceptical of published limits generally. A limit taken from a best-case study describes what an instrument did under favourable conditions. A limit set where performance is reproducible at volume describes what the ordering clinician actually receives.

LC-MS/MS endocrine panel 20 analytes

Analyte	Reportable range	Unit
5α-Dihydrotestosterone scope note	10.125 – 900	ng/dL
11-Deoxycorticosterone	5.625 – 500	ng/dL
11-Deoxycortisol	5.625 – 500	ng/dL
17α-OH-Progesterone	3.375 – 300	ng/dL
17β-Estradiol scope note	10.125 – 900	pg/mL
21-Deoxycortisol	0.1 – 9	ng/mL
25-OH Vitamin D3 scope note	2.25 – 200	ng/mL
Aldosterone	4.5 – 400	ng/dL
Androstenedione	6.75 – 600	ng/dL
Corticosterone	16.875 – 1500	ng/dL
Cortisol	0.315 – 28	µg/dL
Cortisone	0.056 – 5	µg/dL
Dexamethasone	45 – 4000	ng/dL
DHEA (unconjugated) scope note	45 – 4000	ng/dL
DHEA-sulfate	10.125 – 900	µg/dL
Estriol	0.056 – 5	ng/mL
Estrone	10.125 – 900	pg/mL
Pregnenolone scope note	8.4375 – 750	ng/dL
Progesterone	0.3375 – 30	ng/mL
Testosterone, total	13.5 – 1200	ng/dL

5 of these 20 carry a scope note — a plain statement of a clinical question the reportable range does not cover. Those are on the analyte pages, rendered as a callout rather than a footnote.

Toxicology

Toxicology analytes carry no reference interval. What each page publishes is the assay cutoff — the concentration below which the analyte is reported as not detected. That is the meaningful number for a confirmation assay, and results are reported as a measured concentration against it rather than as a presumptive call.

The cutoff applicable to a result is stated on the report for that specimen. Cutoffs for the 65 toxicology analytes are available on request.

Chemistry and hematology

The 64 routine chemistry, immunoassay and hematology analytes run FDA-cleared or FDA-approved assays on automated analysers. Specimen type, tube and measuring range follow the manufacturer's package insert, and reference intervals are established or verified by the laboratory as CLIA requires.

Results from cleared assays are broadly comparable with other laboratories running the same assays. Results from the LC-MS/MS panel are method-specific — which is the point of running it. See methods.

Two configurations, two purposes

Method development and proof-of-concept work runs at enhanced sensitivity, at or near the instrument's demonstrated floor. Production runs at the published limits above.

One consequence is worth stating plainly rather than explaining away each time it surfaces: historical validation data shows concentrations below current reportable limits. The vein-to-capillary study is the clearest example — it was run pre-launch at enhanced sensitivity, because the question was whether capillary collection introduces any difference at all, and the most sensitive configuration is the one most likely to expose one.