Medichecks Sexual health & STIs

Prothrombin Time (INR) Blood Test

Measures your INR to check how well your blood is clotting. Aimed at people on warfarin who need their dose monitored, or investigating unexplained bleeding, clotting or liver problems.

  • Doctor reviewed
Sample
Blood
Collection
In-store clinic
Results in
3 days
Biomarkers
1
Doctor reviewed
Yes
Tests for
  • INR

Test specifications

Provider
Medichecks
Sample type
blood
Collection method
in-store clinic
Turnaround time
3 days
Biomarkers tested
1
At-home test
No
Doctor reviewed
Yes
Gender focus
Both

What's tested

1 biomarker as listed by Medichecks.

Clotting status

  • INR

About this test

This test measures your INR (International Normalised Ratio), which reflects how quickly your blood clots. It's mainly used to monitor people taking warfarin, to check the medication is working at the right level, but it can also help look at liver function or unexplained bleeding or clotting problems.

There isn't a directly comparable group of INR tests tracked on the site for this listing, but among similarly sized tests in this part of our catalogue, £59 sits well below the typical £145 cost. The main limitation on convenience is that you cannot collect the sample at home: it needs a venous draw at Medichecks' Inuvi Clinic in London, because the sample isn't suitable for posting.

The test scores well for value given its price against similarly sized tests, and for clarity, since the listing sets out the biomarker, turnaround and collection detail clearly. It scores lower for collection convenience because there is no home or local clinic option, only the London clinic. As with all Medichecks tests, results come with a doctor's comment, which supports the results and follow-up score.

Who is it for?

This is a sensible option if you are on warfarin and need to check your INR is in the right therapeutic range, or if a clinician has suggested checking your clotting status or liver function. If you notice unexplained bleeding or bruising, it's worth seeing a GP as well as checking your INR. Because there is no home collection option, it works best if you are able to attend Medichecks' Inuvi Clinic in London or already have a reason to be nearby.

The sheet doesn't identify a directly comparable INR test from another provider, so there's no specific cheaper or deeper alternative to point to here.

How it works

This is a blood test collected via a venous draw at Medichecks' Inuvi Clinic in London; the sample is not suitable for posting, so no at-home or other clinic option is offered for this test. Turnaround is around 3 days, and a doctor reviews your result before you receive it.

Pros & cons

Pros

  • Priced well below the typical cost of similarly sized tests in this part of our catalogue.
  • Clear listing: biomarker, turnaround and collection route are all stated upfront.
  • Comes with a doctor's review of your result.

Cons

  • No home collection option; you must attend Medichecks' Inuvi Clinic in London for a venous draw.
  • Only measures one marker (INR), so it will not give wider liver or clotting-disorder context.

Our editorial score

Compare Health Test Score In-clinic-only INR check for warfarin monitoring
Editorial confidence: 10.0/10

At £59, this INR check sits well below the £145 median for similarly sized tests we track, but you'll need to attend Medichecks' Inuvi Clinic in London for a venous draw, since the sample can't be posted. It's aimed mainly at people monitoring warfarin therapy.

Score breakdown

  • Clarity and documentation 8.0/10

    The listing publishes a short description, the full biomarker list, a stated turnaround, clear collection options, the sample type; it does not state what the report looks like.

  • Clinical depth 5.8/10

    1 biomarkers, placing it in the 21st percentile of sexual health tests we track.

  • Collection convenience 3.0/10

    Requires a visit to a clinic; results in around 3 days, slower than similar tests.

  • Results and follow-up 7.0/10

    Results are reviewed by a doctor; the provider does not describe the report format.

  • Trust signals 9.5/10

    Trustpilot 4.5 from 2,477 reviews; accredited lab (UKAS ISO 15189 partner labs); doctor review as standard; trading 25+ years.

  • Value for money 9.5/10

    £59.00 against a median of £145.00 for the 81 similarly sized sexual health tests we track (-59%).

Calculated 13 September 2026 from the facts we hold about this test and provider, using our published scoring formula. Scores are not hand-edited.

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