Elena conducted an investigation to see whether mindfulness practice delivered via a smartphone application was as effective as mindfulness practice delivered in a face-to-face group setting. If people were interested in taking part in Elena's investigation, they could sign up online.

Her participants came from different local community centers and presented with varying levels of mild-to-moderate anxiety. The participants were allocated to one of two groups:

• Condition A: the mindfulness practice was completed using a smartphone app daily.
• Condition B: the mindfulness practice was completed in a weekly face-to-face group session.

Every participant completed four weeks of their assigned practice, after which Elena asked them if their anxiety symptoms had decreased, stayed the same, or increased.