How often are PCRs wrong?

[lackingchristmasspirit]

My husband had a positive PCR result Monday morning. My daughter with the same symptoms was negative.

DD has become increasingly unwell but tested negative again yesterday. The rest of us also negative.

DH lateral flows have all been negative despite a terrible cough.

He is isolating anyway and we are only going for dog walks, and don't plan to change that. But I wondered what are the chances of the PCR being a false negative?

I would get her tested again in a few days. Mine was negative a few days ago, as were all my LFTs, and my PCR came back positive yesterday.

I think it’s far more likely to be a false negative then false positive.

Think I read 1 in 5 negative PCRs were false negatives. Will see if I can find a source.

I don't actually know but I imagine self administered tests do have a fair chance of being false negatives if she hasn't swabbed quite right.

Also know of people who did one, negative, did another a few days later and positive.

Either way, maybe assume the worst if you've got a positive test in the house and she's got symptoms.

Yes we are, I'm just curious.

She's had two negative PCRs and being so unwell I thought they'd show up positive if she was.

We are treating as if positive that is.
I've actually got her a drs appointment for later because I'm a bit concerned about her

Agree it'll be the negatives that are false.

Here's our timeline for some context

DH tested positive on LFT 15/12
Confirmed by PCR 16/12

DS & I negative PCR on 16/12

I had daily negative lateral flows between 15/12 - 19/12

Developed a slight fever late on 19/12 and a slight cough

LFT on 20/12 positive for me

PCR on 20/12 confirmed positive

DS PCR 20/12 - negative

DS develops cough and fever on 21/12

DS LFT positive on 21/11

Awaiting further PCR test for DS (had to order a home test as both parents are now isolating).

Expecting this PCR to be positive now given the LFT (but he's had two negative the last week).

It takes time for there to be enough viral load to test positive. If you're all symptomatic you should isolate and continue to LFT and my bet will be you'll test positive in the coming days.

The only reason I didn't lateral flow my DS every day is because he's only two and its not recommended to do so.

The weird thing is Dh Has had no positive lateral flows as all!

DD has had 2 negative PCRs

It's odd

We’re the opposite , DH testing positive on several LFTs but his pcr was negative. His lines are getting progressively darker on the LFTs so we’ve been for another PCR this morning - the rest of us are negative.
I just don’t understand any of it

You probably feel like you can't trust it @Ellie1311 even if the pcr is negative