Table 1 Description of the four adaptive interventions (AI). N = Nurse, A = App and A + N = App + Nurse

AI1

(N, N^RA^1 − R)

Nurse at stage 1, continue with Nurse at stage 2 if responder, or switch to App at stage 2 if non-responder.

AI2

(N, N^R(A + N)^1 − R)

Nurse at stage 1, continue with Nurse at stage 2 if responder, or provide combination at stage 2 if non-responder.

AI3

(A, A^RN^1 − R)

App at stage 1, continue with App at stage 2 if responder, or switch to Nurse at stage 2 if non-responder.

AI4

(A, A^R(A + N)^1 − R)

App at stage 1, continue with App at stage 2 if responder, or provide combination at stage 2 if non-responder.