Noncompartmental analysis
Set up, run, and review this analysis in Lifescio.
Supported analysis
Time and concentration observations produce linear-up/log-down trapezoidal AUC. The selected last positive terminal points estimate a log-linear elimination slope, half-life and extrapolated area. Dose and route determine clearance or apparent clearance calculations.
Supported scope: The app requires strictly increasing times starting at zero and an appropriate post-peak terminal segment. It does not impute missing or below-quantification values. Extravascular clearance is CL/F because bioavailability is not identified from these data.
Prepare data and configure the analysis
Enter exactly two columns, Time and Concentration, in strictly increasing time order with an observation at time zero. Concentrations must be nonnegative. Supply dose in units consistent with concentration and time, and select extravascular or iv-bolus administration.
Terminal points selects exactly the last k observations, with at least three points. They must be positive and begin at or after the observed peak. The tool does not search for an optimal terminal window, impute time zero, or handle below-quantification values automatically. Integration uses linear-up/log-down trapezoids.
Input reference (4 fields)
Enter your data and prespecified choices. Ranges include both limits. For table fields, use cell editing, Paste data, or Import CSV / TSV. Review whether the first imported row contains headings and map the source columns before applying the import. Empty numeric cells are not treated as zero. Open file is for an exported Lifescio analysis JSON file, not a spreadsheet.
| Input | Format | Allowed range | Guidance |
|---|---|---|---|
| Concentration–time observations | Table | — | Columns in order: Time; Concentration. |
| Dose | Number | 0.000001–1000000 | — |
| Terminal points | Whole number | 3–20 | — |
| Administration | Selection | — | Choices: extravascular, iv-bolus. |
Run and review
- Give the analysis a descriptive name and review every example value. Record units, data preparation, and planning assumptions in Reproducibility & notes. For simulations, record the seed and replication or sampling settings.
- Choose Run analysis. Resolve input errors before interpreting output. In the connected app, a run uses a saved input revision; local preview runs need the page to stay open.
- Review Diagnostics for method limitations, warnings, and available numerical checks. A completed run means computation finished; it does not establish that the assumptions fit your study.
- Use the Result table selector to inspect each output. Editing inputs does not recalculate existing results: an earlier-input notice means you need to run again to obtain matching results.
Understand the outputs
NCA parameters includes observed peak, AUC last, AUC infinity, extrapolated percentage, terminal slope and half-life, apparent or intravenous clearance/volume, and moment-based summaries. Route changes the apparent-parameter labels; it does not estimate bioavailability.
The concentration plot overlays the fitted terminal segment. Diagnostics flag a large extrapolated fraction or weak terminal fit. These flags guide review rather than certify the remaining estimates. The application does not calculate parameter confidence intervals for this single profile.
Troubleshooting and common mistakes
If the terminal fit is rejected, inspect zeros, the selected point count, and whether the final log-concentrations actually decline. Duplicate or unordered times are invalid. Do not replace unquantifiable values with invented positive concentrations just to pass validation.
A high extrapolated percentage warrants better late sampling or a qualified interpretation. If clearance units seem implausible, reconcile dose and concentration units first. Infusions, repeated doses, and population profiles require a more suitable analysis.
After correcting inputs, run again and check that the results belong to the new input snapshot. Increasing simulation draws improves numerical precision only; it does not repair invalid data or an unsuitable model.
Save, compare, and export
In the connected app, Save analysis retains the inputs in your account. Run history lets you inspect earlier runs, each with the input revision it used. In local preview, Save analysis downloads an input file instead; download results before leaving the page.
Use Result + inputs for a JSON archive containing the completed result and its inputs, Download CSV for the selected result table, PDF report for a report, and a chart's SVG button for its figure. Table displays round to three decimals; CSV and JSON exports retain calculation precision. Use those values when assessing a result near a decision boundary.
To reopen an archive, select the matching analysis method and choose Open file. Imported inputs start a new draft; a result archive can also display its retained result. It does not attach itself to an existing account analysis or recompute the result. Save or run the imported draft when you want a new account record.