Posting on behalf of @Peter_MacIsaac:
One of our tissue banks has requested an internal change to OS default units for the molecular class of specimen types (eg. DNA/RNA) from micrograms ug to nanograms ng.
Seeking input from other institutions about how you manage units for this type of micro specimen/aliquot
The issue is that OS allows only a single default unit for each of the 4 major specimen type classes for mass and concentration. If we change then we have to identify all previous specimens stored and adjust their units (in this case multiply by 1000) as changing the units does not change the quantity. As it happens this is not a major issue as we have very few stored specimens of this type and easy to change.
When I ran a query on specimens for DNA/RNA the few we had came up with mass around 10ug – so to change to nanogram would mean recording as 10,000 nanogram? too many zeros for usability and reliable data entry?
However as this change impacts any future users of this type of specimen, would appreciate a crowd sourced view of how this is done elsewhere – ie. do you use micrograms or nanograms
What is the common practice in describing the mass/concentrations of this type of tissue sample.
Dr. Peter MacIsaac
Clinical Research Informatics – Open Specimen Coordinator
Hunter Medical Research Institute
Newcastle Australia.