Reference Value Advisor is a set of macroinstructions for Excel that compute reference intervals using the standard and robust methods with and without generalized Box-Cox data transformation. It also allows to study the effect of continuous covariates on reference intervals.
It can be freely used.
For any series of data presented in an Excel column, the software:
computes the limits by the nonparametric method (when n≥40), and by parametric and robust method from native and generalized Box-Cox transformed values;
when possible, gives the 90% confidence interval for the two limits. These intervals quantify the imprecision of the reference interval limits;
tests the normality of distributions according to Anderson-Darling
tests the symmetry of distributions required by the robust method
detects possible outliers according to Tukey and to Dixon-Reed tests;
shows the distribution of values (dot-plot and histograms) and QQ plots for visual inspection;
gives some observations according to EP28
A reference interval can change with covariates (age, weight,...) leading to a reference interval to each value of the covariates (reference bands) instead of a single reference interval.
The software computes:
parametric reference bands for continuous covariates — with and without Box-Cox transformation — for homoscedastic and heteroscedastic models (the length of the reference interval is free to change with the covariates),
the confidence intervals for these bands
provide a test for the usefulness of the Box-Cox transformation,
a graphical validation of the building of such bands
nonparametric reference bands for a single covariate (experimental).
If you used this software for your article, do not hesitate to cite the companion paper :
Geffré A, Concordet D, Braun JP, Trumel C. Reference Value Advisor: a new freeware set of macroinstructions to calculate reference intervals with Microsoft Excel, Vet Clin Pathol. 2011 40(1) 107-112. file available here
Reference Value Advisor V 2.1 is fully compatible with Office 2010. A version running with Office 2007 will be available by the end of march 2012.
Reference Value Advisor V 2.1 is composed of six files:
These six files are zipped in a single file.
Last upgrade: february 29th 2012