Lateral Flow Tests

GDB2222

The government is doling out rapid Covid test kits for home use, if you want them.

https://www.gov.uk/order-coronavirus-rapid-lateral-flow-tests

Sorry if that has been posted elsewhere.


These are less accurate than PCR tests that are sent off to a laboratory, but results only take 30 minutes.

They use a swab like the PCR tests.

JamoLew

Indeed - not without its flaws but useful nevertheless and it will attract the haters

IMO this would have been better rolled out mid Dec - but there may be good reasons why not

I suspect these will be the way to go to opening up mass attendance events

Batesy1976

JamoLew said:

Indeed - not without its flaws but useful nevertheless and it will attract the haters

IMO this would have been better rolled out mid Dec - but there may be good reasons why not

I suspect these will be the way to go to opening up mass attendance events

As long as the Government doesn't get the results of the test I don't care.


They're too inaccurate for mass testing if the results actually get recorded (and worse yet given to the general public.)  If everyone in the country took a lateral flow test every day they'd be 67000 false positives a day, more than we've ever recorded as, loosely speaking, "confirmed cases". We'd never get out of this mess.

JamoLew

Batesy1976 said:

JamoLew said:

Indeed - not without its flaws but useful nevertheless and it will attract the haters

IMO this would have been better rolled out mid Dec - but there may be good reasons why not

I suspect these will be the way to go to opening up mass attendance events

As long as the Government doesn't get the results of the test I don't care.


They're too inaccurate for mass testing if the results actually get recorded (and worse yet given to the general public.)  If everyone in the country took a lateral flow test every day they'd be 67000 false positives a day, more than we've ever recorded as, loosely speaking, "confirmed cases". We'd never get out of this mess.

Plus as "herd immunity" is achieved you will get more false positives than real positives (Bayes Theorem)

I think the advice with the LFT is to get and get a PCR test if positive is indicated

Currently a discussion here: http://forums.pepipoo.com/index.php?showtopic=138789

Re the bit in bold - 100% agree. I have great respect for Chris Whitty (and co) but he does come across as very pessimistic and like a good number of clinicians is very much in the "save a single life at any cost" brigade. Whilst in normal times this is a great principle, it doesn't work in these current times

GDB2222

Initially, people were worried that the swabbing would be painful, but it really isn’t. Ticklish, yes, but not painful. 

I have done a couple of tests, and I found it difficult to self administer the swabs. It helps to use a mirror. Or get someone else to do it for you.

MattMattMattUK

Whilst lateral flow tests have a use at time of high infection, the current low infection rates make them ineffective. They have a false positive rate that is higher than the current infection rate, so more than half of positive test results would in fact be wrong. On top of that they miss more than half of all positive tests, so giving infected people a false sense of security. 

I have been tested multiple times due to work, I agree testing has a very important role to play, but the use of LFTs in a period of incredibly low infection rates is of no real benefit and might even be a negative.

MattMattMattUK

GDB2222 said:

Initially, people were worried that the swabbing would be painful, but it really isn’t. Ticklish, yes, but not painful. 

I have done a couple of tests, and I found it difficult to self administer the swabs. It helps to use a mirror. Or get someone else to do it for you.

I agree, the nose swab made me feel like like I needed to sneeze but it was not painful and the throat swab whilst not fun was not unpleasant. 

When not swabbed by the tester, the throat swab I use a mirror, the nose swab I got used to pretty easily.

GDB2222

Batesy1976 said:

JamoLew said:

Indeed - not without its flaws but useful nevertheless and it will attract the haters

IMO this would have been better rolled out mid Dec - but there may be good reasons why not

I suspect these will be the way to go to opening up mass attendance events

As long as the Government doesn't get the results of the test I don't care.


They're too inaccurate for mass testing if the results actually get recorded (and worse yet given to the general public.)  If everyone in the country took a lateral flow test every day they'd be 67000 false positives a day, more than we've ever recorded as, loosely speaking, "confirmed cases". We'd never get out of this mess.

In case it’s not obvious to anyone, there’s no way that anybody can get the test results unless you tell them.

If you got a positive result from one of these tests, is it worth repeating the test?

JJ_Egan

Yes i would repeat the test before reporting .

JamoLew

GDB2222 said:

Batesy1976 said:

JamoLew said:

Indeed - not without its flaws but useful nevertheless and it will attract the haters

IMO this would have been better rolled out mid Dec - but there may be good reasons why not

I suspect these will be the way to go to opening up mass attendance events

As long as the Government doesn't get the results of the test I don't care.


They're too inaccurate for mass testing if the results actually get recorded (and worse yet given to the general public.)  If everyone in the country took a lateral flow test every day they'd be 67000 false positives a day, more than we've ever recorded as, loosely speaking, "confirmed cases". We'd never get out of this mess.

In case it’s not obvious to anyone, there’s no way that anybody can get the test results unless you tell them.

If you got a positive result from one of these tests, is it worth repeating the test?

Absolutely - repeating a positive test is what we were directed to do via work (NHS) 

A double positive somewhat removes the false positives but should/must (?) be followed up with a PCR

We have moved onto weekly LAMP tests now as opposed to twice weekly LFT

Sea_Shell

Under what circumstances would an LFT give a void result?

Would it be a faulty test kit, or does it detect that you've not done the swab properly?