Reference intervals
Reference interval verification
To check that a reference interval fits the population your laboratory serves, you test a group of healthy subjects and count how many fall outside it. Enter the results and LabRuns does the counting for each partition and applies the decision rule you saved.
Your first week is free, with no card needed. See pricing.
Collection plan
Have the claimed limits and their unit ready, decide who is eligible, and settle any separate population groups (partitions), such as age groups. Each person gets one coded subject ID and belongs to one partition.
Suggested starting design: 20 different eligible subjects per partition, 1 result each. Two partitions: 40 people, 40 results.
Limits and decision rule
Choose a two-sided interval, a lower reference limit or an upper reference limit. A value exactly on a claimed limit counts as inside.
A new study starts with one stage of 20 subjects. Accept the interval when no more than 2 fall outside it, following the 2-of-20 criterion of CLSI EP28-A3c (2010) §11.2. Reject it when 3 or more fall outside. LabRuns judges each partition separately and takes subjects in the order you entered them.
Change the numbers or add stages to test more subjects before deciding. Each stage can count all subjects tested so far or only the new subjects in that stage. You can also set a minimum percentage inside the interval, or clear the stages and report the counts alone. The report lists every stage with its count, the subjects outside and its outcome.
Results and report
Import, paste or type each subject's ID and result, with a partition if you use them. Repeat draws under one ID are averaged so each person counts once, and an ineligible result can be excluded with its reason.
Results show how many subjects fell below, within and above the limits, the percentage inside and the outcome under your rule, with a plot of every subject against the limits.
Records
Each saved calculation keeps the data and limits it used. History lists every saved calculation and signed report, each with its own PDF. Prepare an evidence binder with the report versions you choose, grouped by analyte or analyzer, and download the combined PDF and supporting archive.
Example
Try the study with the example results file: white blood cell counts in two partitions, with repeat draws and values exactly on the limits. The example guide takes you through it.
Guides
Read the bench guide before you collect, or follow an example study from setup to its signed report.
Run your next reference interval verification.
Start from the suggested collection plan, bring in your analyzer results and sign the report once your laboratory has made its decision.