In-House vs Reference Laboratory: The Real Cost Is the Wait

Quick Answer — Comparing cartridge price with laboratory price is the wrong comparison, and it is the one most clinics make. The correct comparison is fully loaded cost per test — cartridge, controls, staff time, instrument — against fully loaded send-out cost including the clinical consequence of a delay. Once the delay is priced, the split is usually obvious: in-clinic for decisions, send-out for everything else.

The comparison, done properly

Cost component	In-house	Send-out
Per-test reagent	Higher	Lower
Controls and QC	Clinic’s time and materials	Included in laboratory operation
Staff time	Collection + run + record	Collection + packaging + courier
Transport, packaging	None	Real, and often forgotten
Delay to result	Minutes	Hours to days
Consequence of delay	Minimal	Hospitalisation, second visit, empirical treatment
Result provenance	Your own record	Accredited laboratory report
Menu breadth	Limited	Broad

Pricing the delay

The delay is not an abstraction. In a suspect parvovirus case it is a day of ward space and cohort exposure. In a breeding management case it is a cycle. In a dyspnoeic cat it is diuretics started blind. In post-operative monitoring it is a complication identified a day later.

Data pending. This section reports measured values from internal validation studies. They are published once the supporting study is complete; the current report is available from technical support on request.

The honest version of this calculation includes the tests that would not have changed anything — because those are the ones that make in-house capacity expensive if the menu is bought indiscriminately.

Where send-out is the right answer

1. Rare analytes where the cartridge would expire before use.
2. Batch screening — a breeding programme, a study cohort, a shelter intake panel.
3. Confirmatory testing where a second method is the point.
4. Traceability-sensitive work — regulatory, legal, research endpoints.
5. Anything that will not be acted on today.

Where in-house wins

1. Isolation decisions — a positive or negative result changes where the animal goes within the hour.
2. Treatment decisions in unstable patients — fluids, antibiotics, diuretics.
3. Time-critical breeding decisions.
4. Clients who will not return for the result.
5. Outbreak settings where transmission continues while a batch is pending.

The hybrid rule

The useful decision rule is per-test, not per-clinic:

Test characteristic	Where it belongs
Changes action within hours	In-house
Changes action within a day, animal stable	Either — cost decides
Screens asymptomatic animals	Send-out, or not at all
Confirms a diagnosis already suspected	Send-out unless timing matters
Uncommon, low volume	Send-out

Data pending. This section reports measured values from internal validation studies. They are published once the supporting study is complete; the current report is available from technical support on request.

The comparison nobody publishes

Most vendor comparisons assume every in-house test changes a decision and ignore the expired-cartridge problem. An honest page states the opposite: in-house capacity is efficient when the menu is narrow and used frequently, and expensive when it is broad and used occasionally.

Six traps

1. Comparing reagent price with laboratory price. Ignores the delay and the overheads.
2. Buying a broad menu. Expiry is a real cost line.
3. Forgetting staff time. Especially in understaffed clinics.
4. Ignoring the tests that did not change anything. They are part of the economics.
5. Sending out tests that are decided today. The delay is the whole point.
6. Comparing results across methods later. Bias, not equivalence.

The Author’s Take

Position. The honest commercial position is “in-house for decisions, send-out for everything else” — and a vendor that says this sells fewer menus and keeps more accounts.

Reasoning. Clinics that buy a broad in-house menu to “save money” typically discover expiry and underuse within a year, and the resulting disappointment attaches to the platform rather than to the purchasing decision. A vendor that helps the clinic size the menu to its decision load ends up with a customer who uses the instrument daily, renews consumables predictably, and recommends it to peers — because it did what it was bought for. The narrower sale is the durable one, and in a category where trust is the scarce resource, that is the better trade.

Disclosure. This page is economic and workflow guidance, not a performance claim. Figures marked indicate where platform pricing, menu boundaries and clinic cost models must be inserted.

Sources

1. Reference to be added.
2. Reference to be added.
3. Reference to be added.