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This guide explains what a nucleic acid amplification test is, how the main methods differ, and why turnaround time and sensitivity vary so much between tests. It is general method and laboratory information, not medical advice, and it does not tell anyone how to interpret a personal result.
Short answer: what is a nucleic acid amplification test?
A nucleic acid amplification test (NAAT) detects a target piece of DNA or RNA by first making many copies of it, so very small amounts can be detected. A “PCR NAAT” is a NAAT that uses the polymerase chain reaction, with a reverse transcription step when the target is RNA. How long it takes depends on the test: the CDC describes point-of-care NAATs that can return a result within minutes and laboratory-based NAATs that take from under an hour to more than a day.
Definition and scope
The CDC’s NAAT page states that the procedure works by first amplifying, or making many copies of, the genetic material of the target, which lets the test detect very small amounts. That page was written for SARS-CoV-2 testing, so this guide uses it for the general principle only. The same logic applies to any NAAT, whatever the target organism or sequence.
NAAT is therefore a category, not a single technique. The CDC names RT-PCR, LAMP, NEAR, TMA, HDA, CRISPR-based and SDA methods under the NAAT umbrella. If you came here from a result page that only says “PCR”, that is one family inside the category.
What is amplification of nucleic acids?
Amplification means enzymatically copying a chosen target sequence many times over, either by repeating temperature cycles or by holding one constant temperature (isothermal methods). A detection step then reads the copies, for example by fluorescence, color change, lateral flow or a chemiluminescent probe. The amplification step is what separates a NAAT from a test that looks for the target directly.
How a NAAT works in practice
A NAAT workflow generally runs through four stages, as described across the methods in a peer-reviewed review of NAAT technologies (Khan et al., Analytical Chemistry 2024, PMC11112543):
- Sample collection.
- Nucleic acid extraction and purification.
- Amplification, by thermal cycling or isothermal reaction.
- Detection and interpretation.
Each stage has its own failure mode, which is where laboratory staff spend most of their attention, as the section on where it matters for labs below shows.
How long does a NAAT test take?
There is no single answer, because the label covers very different test formats. The CDC states that some rapid point-of-care NAATs can provide a result within minutes, while the time to complete laboratory-based NAATs ranges from less than an hour to more than a day. The reviewed literature adds that conventional PCR delivers results within a few hours with high throughput. Turnaround depends on the method, whether the test runs at the point of care or in a laboratory, and the laboratory’s own workflow, so the figure to trust is the one in the specific test’s instructions for use.
Types of NAAT compared
The table covers only the three methods for which the review gives specific, citable conditions. The temperatures for PCR are example conditions from the review, not a protocol.
| Method | Temperature profile | Key mechanism | Reported detail |
|---|---|---|---|
| PCR / RT-PCR | Thermal cycling; example conditions 95 °C denaturation, 58 °C annealing, 72 °C extension | Repeated cycles copy the target; an RT step converts RNA to cDNA first | Results within a few hours with high throughput |
| LAMP | Constant, about 60 to 65 °C (isothermal) | Four primers recognise six target regions; readouts can be colorimetric, fluorescent or lateral flow | One described protocol runs at 65 °C for 60 minutes |
| TMA | Isothermal | Reverse transcription plus RNA polymerase transcription, after magnetic-particle target capture and washing | Increase by a factor of 10 billion within 15 to 30 minutes |
For a wider look at LAMP, NASBA, HDA and SDA against PCR, see isothermal amplification. For the real-time PCR workflow, see the qPCR and RT-qPCR guide, and for a related enzymatic route, recombinase polymerase amplification.
Where it matters for labs, clinics and supply decisions
A failure-point checklist for each stage
- Extraction and cleanup: the review describes a TMA step in which magnetic particles are washed so that leftover specimen matrix, which can contain amplification inhibitors, is removed.
- Amplification: the review describes UDG-based systems that remove traces of earlier amplification products from a reaction, a measure against carryover into later reactions. It also notes that isothermal methods make primer design and multiplexing harder, and that one RT-LAMP test was less sensitive than real-time RT-PCR.
- Setting: the CDC states that sensitivity varies by test, and that laboratory-based NAATs generally have higher sensitivity than point-of-care tests.
Consumables that sit in the workflow
The stages above map onto categories of laboratory consumables: specimen collection devices such as an oropharyngeal swab, reaction vessels such as a PCR tube, and plate formats such as a microplate. Which product suits a given assay is set by that assay’s manufacturer instructions, not by this guide.
Common misunderstandings
Not every NAAT is PCR
PCR is the best-known NAAT, but LAMP, TMA, HDA, SDA and other methods are NAATs too. “PCR NAAT” specifically means the PCR-based kind.
All NAATs are not equally sensitive
The CDC states that sensitivity varies by test and that laboratory-based NAATs generally have higher sensitivity than point-of-care tests, so two tests that both carry the NAAT label are not interchangeable. This is method-level information, not a rule for any individual result.
Frequently asked questions
What does PCR NAAT mean?
It means a nucleic acid amplification test that uses the polymerase chain reaction as its amplification method, adding a reverse transcription step first when the target is RNA. PCR is one of several amplification methods grouped under NAAT.
How long does a NAAT test take?
According to the CDC, anywhere from minutes for some rapid point-of-care NAATs to more than a day for laboratory-based NAATs, with many laboratory tests falling between under an hour and a day. The test’s instructions for use give the figure that applies.
What is amplification of nucleic acids?
It is the enzymatic copying of a target DNA or RNA sequence so that a detection step can read it. It can be done by temperature cycling (PCR) or at a constant temperature (isothermal methods such as LAMP).
What does NAAT stand for?
Nucleic acid amplification test. It is a subset of nucleic acid tests (NAT) that includes an amplification step.
Sources
- CDC, “Nucleic Acid Amplification Tests (NAATs)” (archived page, last updated May 12, 2023), https://archive.cdc.gov/www_cdc_gov/coronavirus/2019-ncov/lab/naats.html. Checked 2026-11-01.
- Khan SF et al., review of nucleic acid amplification technologies, Analytical Chemistry 2024;96(20):8124-8146, https://pmc.ncbi.nlm.nih.gov/articles/PMC11112543/. Checked 2026-11-01.
