Thread by @nicolamlow

This paper is (mostly) being interpreted as showing that #SARSCoV2 viral load is higher in children than adults. But is it? jpeds.com/article/S0022-… @EricTopol @DoctorYasmin @angie_rasmussen @skepteis @apsmunro @mugecevik My pedantic post-publication peer review thread (1/n)

https://twitter.com/EricTopol/status/1296453662022291457

The headline result on Tweets is that VL is higher in children than adults. But the same p-value seems to appear with different comparisons in different parts of the manuscript. Have a look. NB: I am not a fan of p-values or sub-group comparisons (2/n)

Abstract: “Nasopharyngeal viral load was highest in children in the first 2 days of symptoms, significantly higher than hospitalized adults with severe disease (P = .002).

So, in the first 2 days, when there were 2 adults and 9 children?

(3/n)

Or,
Results, “Viral load in children in the asymptomatic/early infection phase was significantly higher than in hospitalized adults with severe disease with over 7 days of symptoms (P=0.002) (Figure 2, B).”

So, children ‘early’ (maybe <7 days) vs. adults >7 days?

(4/n)

Or,
Figure 2B, when the p-value 0.002 seems to cover entire time period, overall, between children and adults.
But wait,
Results “Pediatric patients displayed no apparent difference in viral load compared with adults requiring intubation for severe SARS-CoV-2 infection..." 5/n

And,
Discussion: “...there was no age correlation with viral load, indicating that infants through young adults can carry equally high levels of virus.”

Crystal clear? It would help if we knew who were the children and adults enrolled in the study, right? (6/n)

Abstract: Study design, doesn’t mention adults. But they are in Results.

Methods, end of para 1, “For the virology and antibody studies, adult patients being evaluated for COVID-19 in the outpatient or inpatient setting were enrolled through the...COVID-19 Biorepository” (7/n)

Results, Patient demographics, doesn’t mention any adults. But then they appear in Tables, Figures and text.

Summary: we don’t really know who was in the comparison group of adults. There are no comparisons of enrolled and not enrolled children or adults, or case mix (8/n)

It would really help to understand if we knew what were the planned analyses and hypotheses. I didn't really get a feeling for this,

Methods: “Prism software was used to analyze and graph data.”

(9/n)

Finally, we should be careful not to extrapolate from RT-PCR assessed viral load to transmission, but

Discussion: “Potential transmission of SARS-CoV-2 between children and families should be considered when designing strategies to mitigate the COVID-19 pandemic.” (10/n)

#SARSCoV2 in children and adults is important. There are interesting and unanswered questions about relative contributions to transmission. But please study, report and interpret carefully. As @apsmunro says "We must do better. Too much is at stake and people are so scared."

@threadreaderapp unroll please