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Table 1 Detection of viruses in NPA and fNS specimens compared with total viral findings by either method

From: Flocked nasal swab versus nasopharyngeal aspirate for detection of respiratory tract viruses in immunocompromised adults: a matched comparative study

Virus No. of samples in which virus was detected by: Total no. Sensitivityafor fNS (%) Mean differencebin Ct values (range) Agreementcbetween NPA and fNS (95% CI d)
  Both methods NPA only fNS only     
Rhinovirus 7 2 0 9 78 3.2 (-2.0-6.5) 0.86 (0.68-1.05)
RSV A 1 1 1 3   5.8  
RSV B 2 0 0 2   2.2 (5.6-9.9)  
Influenza A 0 1 0 1   N/A  
Influenza B 1 1 0 2   15.5  
Bocavirus 0 1 0 1   N/A  
Enterovirus 0 1 0 1   N/A  
Metapneumovirus 0 0 1 1   N/A  
Any virus 11 7 2 20 65 5.1 (-2.0-15.5) 0.66 (0.44-0.87)
  1. NOTE. NPA, nasopharyngeal aspirate; fNS, flocked nasal swab; Ct, cycle of threshold; CI, confidence interval.
  2. a Percentage of positive samples from fNS in relation to the total number of pairs with positive results from any of specimens.
  3. b The Ct value for the flocked nasal swab minus the corresponding Ct value for NPA.
  4. c Cohen's kappa: >0.8, almost perfect agreement; 0.6-0.8, substantial agreement; 0.4-0.6, moderate agreement; <0.4, poor agreement.
  5. d CI, confidence interval.