Table 1. Scoring system for evaluation of published reports describing seroprevalence studies of zoonotic influenza virus infections.
| Parameter | Maximum score | Individual scores | |||
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | ||
| Control group | 6 | No | Unmatched | Age-matched (2)a Sex-matched (2)a Area-matched (2)a |
NA |
| Repeated samplingb | 2 | No | NA | Yes | NA |
| Correction for age or reporting of study participants’ age groupsc | 1 | No | Yes | NA | NA |
| Human vaccination status reported | 1 | No | Yes | NA | NA |
| Testing included human influenza type(s) | 1 | No | Yes | NA | NA |
| Other evidence | 3 | No | Serological evidence in animals to which humans were exposed | Virological evidenced in animals to which humans were exposed | Virological evidenced in human study participants |
| Laboratory method | 5 (Table 2) |
NA | NA | NA | NA |
| Total | 18 | NA | NA | NA | NA |
NA: not applicable.
a Two points are added to the final scoring result for age-matched, sex-matched and area-matched controls (same country), adding up to a maximum score of six.
b Sampling to assess changes in antibody levels.
c Score applied only if there was no age-matched control group.
d Virus detection by culture or (real-time) reverse transcription-polymerase chain reaction (rtRT-PCR) and sequencing is listed as virological evidence.