Table 2

Characteristics of serological (index) and reference tests in included studies (n=40)

Characteristics*No (%)
Commercial serological kit as index test: 
 Yes23 (58)
 No16 (40)
 Unclear1 (3)
Class of immunoglobulin measured by index test: 
 IgM24 (60)
 IgG25 (63)
 IgM and IgG17 (43)
 IgA3 (8)
 Total Ig4 (10)
Antigen target of immunoglobulin measured by index test: 
 Surface protein11 (28)
 Nucleocapsid protein8 (20)
 Surface and nucleocapsid proteins14 (35)
 Not reported11 (28)
Type of specimen for RT-PCR reference test†: 
 Nasopharyngeal16 (40)
 Sputum, saliva, or oral, throat, or pharyngeal8 (8)
 Not reported15 (38)
No of specimens for RT-PCR reference test†: 
 26 (15)
 1 or not reported33 (85)

RT-PCR=reverse transcriptase polymerase chain reaction.

  • * See supplementary table S3 for additional test characteristics of each study. Supplementary table S4 lists the commercial kits.

  • Denominator is 39 studies reporting sensitivity.