Each study type has a Method ID such as LMS-CMP-1.12. You'll find it in the report's C Audit trail (with Include technical details) and in the Calculation file (JSON). When a method's numbers change, it gets a new ID. Earlier calculations and reports keep theirs. The checks behind each method are in Validation. See History and revisions.
Methods by study type#
| Study type | Method ID | Main estimators | Main sources |
|---|---|---|---|
| Descriptive summary | LMS-DESC-1.7 | Mean, sample SD (n − 1), CV, type-7 quartiles, Student t CI for the mean | NIST/SEMATECH e-Handbook §1.3.5.6 and §1.3.5.2 |
| Repeatability | LMS-RPT-1.7 | As descriptive, for one material, day and run per level | NIST/SEMATECH e-Handbook §1.3.5.6 and §1.3.5.2 |
| Multi-day precision | LMS-PREC-1.7 | Balanced nested variance components for days, runs and replicates. Repeatability and within-laboratory SD and CV | NIST/SEMATECH nested designs; Chakravarthy et al. 2019 worked example |
| Bias against an assigned value | LMS-ACC-1.10 | Mean minus assigned value, percent bias, recovery, Student t bias CI, combined uncertainty | NIST/SEMATECH e-Handbook §1.3.5.2 |
| Method comparison | LMS-CMP-1.12 | Specimen differences against the allowable difference, with at least 95% of at least 5 specimens within. Ordinary least squares, Deming, weighted Deming and Passing-Bablok on specimen means. Mean bias and limits of agreement. Bias at decision levels | Linnet 1990 and 1993 (via the mcr package); Passing and Bablok 1983; Bilić-Zulle 2011; Giavarina 2015 |
| Instrument comparison | LMS-ICOMP-1.7 | Specimen differences from the comparator instrument against the allowable difference, with at least 95% of at least 5 specimens within. Mean differences and limits of agreement on cell means | NIST/SEMATECH e-Handbook §1.3.5.6 and §1.3.5.2 |
| Dilution verification | LMS-AMI-1.7 | Dilution factors, corrected results and recovery. Verified range from accepted recoveries | Generic dilution arithmetic |
| Reagent lot comparison | LMS-LOT-1.10 | New-minus-previous difference for each patient specimen against the greater of an absolute or percentage-of-previous allowance. Every specimen, at least 2, must be within and the plan complete. Supporting mean differences, Student t intervals and imprecision | NIST/SEMATECH e-Handbook §1.3.5.2 |
| Linearity | LMS-LIN-1.11 | Least-squares line through level means. Deviation from the line and recovery at each level. Optional reportable-range check: a level within the proximity allowance of each limit. Optional expected values from an equally spaced kit, two levels held true | NIST/SEMATECH e-Handbook §1.3.5.2 and §1.3.5.6; Xiao and Chambliss 2023 (endpoint proximity) |
| Reference interval verification | LMS-RIV-1.9 | Counts of subjects below, within and above the claimed interval, compared with your staged rule | Counts against your decision rule |
| Reference interval establishment | LMS-RIE-1.12 | Nonparametric percentiles (type 6) with exact rank-based CIs, or parametric or log-normal limits when you choose them | Horowitz 2008; Bland, An Introduction to Medical Statistics; StatsDirect reference range (log-normal) |
| Qualitative agreement | LMS-QAL-1.3 | PPA, NPA and overall agreement with Wilson CIs. Kappa and McNemar as supplements | FDA 2007 guidance on diagnostic test studies; Fleiss, Cohen and Everitt 1969; Newcombe 1998 |
| Near-cutoff precision | LMS-QCO-1.4 | Hit rates with Wilson CIs. Probit fit. C5, C50 and C95 with Fieller limits | SAS/STAT PROC PROBIT documentation |
| Detection limits: LoB, LoD, LoQ | LMS-LOB-1.5, LMS-LOD-1.6, LMS-LOQ-1.7 | Percentile or parametric LoB. Parametric LoD from LoB and pooled low-level SD. Goal-based LoQ | Armbruster and Pry 2008; NIST/SEMATECH §1.3.5.8 and §7.2.4.1 |
| Sample carryover, 21-position sequence | LMS-CO-2.2 | Mean low-after-high minus mean low-after-low in each run, against 3 SD or an absolute limit | pSMILE carryover guideline VAL 2015 |
| Sample carryover, historical high-then-low design | LMS-CO-1.4 | Broughton carryover percentage and low-result bias in each run | Broughton 1984; Haeckel 1988 |
| Interference | LMS-INT-1.9 | Test minus vehicle-matched control, Welch–Satterthwaite intervals | NIST/SEMATECH e-Handbook §1.3.5.3 |
| Stability | LMS-STB-1.4 | Change from baseline at each condition and time, paired or independent design | NIST/SEMATECH e-Handbook §1.3.5.2 and §1.3.5.3 |
| Sigma metric | LMS-SIG-1.0 | (TEa% − |bias%|) / CV% at a stated concentration. Descriptive | Westgard, Bayat and Westgard 2019; Coskun et al. 2019 (counter-position) |
| QC targets (ADM export) | LMS-ADM-QC-1.3 | Candidate target mean, sample SD (n − 1) and CV by instrument, lot, analyte and level. Optional mean ± 1, 2 and 3 SD ranges and combined performance across chosen instruments. Descriptive | Sample SD and CV definitions |
Supporting methods:
| Method ID | Used for |
|---|---|
LMS-CRITERIA-1.0 | Comparing estimates with acceptance criteria |
LMS-DIAG-1.0 | Normal Q–Q plot and box plot in descriptive, repeatability, multi-day precision and reference interval studies |
LMS-RI-REVIEW-1.0 | Flags values outside the box-plot whiskers in reference interval studies. Flagged values stay in the result |
Calculations use NumPy and SciPy. The report's audit trail prints their versions.
Calculation details#
The Results stage lists the method statements and sources under Methods and sources. So does the report's A Methods appendix when Include technical details is on. Each method chapter gives the formulas.