Two quotations with the same product name can cover different molecular forms, quantities or documentation. A fair comparison first establishes what each offer includes, then calculates the cost of meeting the same defined research requirement.
Give every quotation the same reference point
Use a dated requirement sheet identifying the material, amount basis, number of containers and essential supporting information. Check which version each supplier has quoted against.
UC Davis procurement guidance identifies quotation references, delivery and payment terms, validity and conditions as features of a formal quote. Those fields help keep an offer interpretable; the university’s internal purchasing rules are not universal rules for research laboratories.UC Davis Supply Chain Management — Price Justification for Requested Purchases (opens in a new tab)
Do not compare a current written offer with an old catalogue price as though both have the same status. Record the date, validity and any unresolved assumptions for each entry.
If one supplier proposes an alternative molecular form, place it in a separate comparison until the researcher has assessed the substitution. Price arithmetic cannot decide scientific equivalence.
Calculate the cost of the defined requirement
| Cost or condition | Offer A | Offer B |
|---|---|---|
| Equivalent defined material amount | £80 | £95 |
| Required additional result | £20 extra | Included |
| Delivery | £10 | £5 |
| Comparable total before any applicable tax | £110 | £100 |
These invented figures show how the lower material price can produce a higher total for the same documented requirement. They are not Novum prices, tax advice or quotations from named suppliers.
The comparison only works because the material and required result are assumed equivalent for the example. If one result has a different scope, the total alone cannot determine which offer meets the requirement.
Record currency, taxes where applicable and other charges consistently. If an item is unknown, leave it unresolved rather than assigning zero and making the offer look artificially cheaper.
Keep non-price differences visible
Lead time, minimum quantity and lot availability can affect whether an offer fits the study. Document these as separate decision factors instead of hiding them inside an unexplained overall score.
A larger pack may have a lower unit price while requiring more total expenditure and supplying material the project has no defined need for. Compare the requested usable amount as well as the nominal pack size.
For repeat work, ask whether a quoted lot is identified or whether the supplier can only confirm the product. Do not treat a general availability statement as a reservation or a guarantee of future lot continuity.
Retain the comparison and the accepted scope
Save the source quotations alongside the comparison, including any clarification that changed a line item. A spreadsheet total should be traceable to the offer rather than replacing it.
Describe the selection reason in terms of the study requirement: for example, a complete evidence package within the required schedule, or the lowest comparable cost among suitable offers. Avoid declaring a supplier universally best.
Before ordering, ensure the selected scope is reflected in the final confirmation. A useful comparison loses its value if the actual order silently omits the condition that made the offer suitable.
Sources and further detail
- UC Davis Supply Chain Management — Price Justification for Requested Purchases (opens in a new tab)
Institutional guidance checked for identifiable quote terms. Original comparison excludes institution-specific thresholds and does not prescribe tax or purchasing-law treatment.
Sources checked 20 September 2026. Assessment examples are original illustrations, not vendor rankings, audits or Novum supplier-process claims. This article has not undergone independent scientific peer review.