The study Attributes and predictors of Long-COVID: analysis of COVID cases and their symptoms collected by the Covid Symptoms Study App is a prospective observational cohort study of COVID-19 symptoms in a subset of 4182 users of the COVID Symptom Study app meeting inclusion criteria.
Briefly, the subset comprised individuals
- who had tested positive for SARS-CoV2 by PCR swab testing
- who logged as “feeling physically normal” before the start of illness (up to 14d ays before testing) so that we could determine onset.
From Table 1. "Characteristics of COVID-19 by duration of symptoms" contains values in brackets() and i would like to know what they mean
| A | B | C | D | | Overall | Short | LC28 | LC56 | Remark Number | 4182 | 1591 | 558 | 189 | A-B-C-D = 1844 question 7 Age (years) | 42.8(13.4)| 40.1(13.6)| 48.9(12.7)| 50.9(12.5)| questions 1 to 3 BMI | 27.3(5.9) | 26.8(5.7) | 27.5(5.7) | 27.5(5.8) | question 4
Questions 5 and 6 concerns line 111:
Cardiac symptoms (palpitations, tachycardia) were over-represented in the LC28 group (6.1%) compared to in short-COVID (0.5%) (p<0.0005)
My understanding (Q5, Q6)
I assume that p stand for p-value. According to exclusions of null hypothesis (often denoted H0) the null hypothesis is a default hypothesis that there is no difference between two measured phenomena.
H0is the hypothesis that there is no correlation between cardiac symptoms among short-covid compared to LC28 than the likelihood / probability of this hypothesis is very low (0.0005)?
Age (years)What does
42.8 (13.4)mean - is 42.8 the median age and 13.4 Interquartile range (IQR) from 25% to 75%?
13.4is the IQR does that mean the lower boundary (25%) age is 29.4 years
(42.8 - 13.4)or 36.1 years
(42.8 - (13.4/2))?
42.8 (13.4)means something different could you explain?
27.5(5.8)mean regarding body mass index?
(p<0.0005)mean the p-value (likelyhood) for no correlation?
- Is my understanding correct?
- Does anyone know what is up with the delta of 1844 persons? Are they without symptoms?