Which supplement works better to reduce severity of the common cold: echinacea angustifolia or echinacea purpurea?

Ratings at a Glance

Supplement	Effectiveness Rating	Confidence Rating
Echinacea Angustifolia
Echinacea Purpurea

Effectiveness Rating: Echinacea Angustifolia vs Echinacea Purpurea

The effectiveness rating is a measure of the supplements' ability to reduce severity of the common cold. This rating answers the question of whether or not a supplement does what it claims. The evidence shows echinacea purpurea is better than echinacea angustifolia in its ability to reduce severity of the common cold. Echinacea Purpurea should provide some positive results while echinacea angustifolia will not.

Confidence Rating: Echinacea Angustifolia vs Echinacea Purpurea

Another factor to take into account when comparing supplements is the confidence rating. This rating is a measure of how valid each supplement's effectiveness rating is. Remember, the confidence rating is a measure of how much you can trust the effectiveness rating. This rating is based on how many studies are included in the database on a supplement's claims. Ideally, you want a high effectiveness AND confidence rating.

Both echinacea angustifolia and echinacea purpurea have low confidence ratings. This means neither supplement has an adequate amount of research to back up this claim. A low confidence rating questions the validity of the effectiveness rating.