Mixing different air quality indexes AQI within the same device_class AQI?

There are many different air quality index (AQI) that are calculated in many different ways (https://en.wikipedia.org/wiki/Air_quality_index#)

  • US AQI,
  • CAQI
  • WAQI
  • EAQI,
  • China AQI,
  • etc…

Home assistant has the device class: aqi: Air Quality Index (unitless).
(Sensor - Home Assistant)

Should this device class only be used for a specific AIQ (for exmample US AQI) or is it meant to be used with a mix of different type of aqi’s?