Table 2

Conceptualisation of some representative forms of iCBT or control conditions according to a component-level perspective

Interventions or controlsPossible decompositions into components
Waiting list w (±pl±pe±dt)±ff
No treatment ±ff
Attention/psychological placebo (APP) pl±ff
Treatment as usual (TAU)* pl+dt±ff
Psychoeducation (PE)† pl+pe±rp±dt±(ae/he)±tg±ff
Relaxation therapy† pl(±pe)+re±rp±dt±(ae/he)±tg±ff±hw
Cognitive therapy† pl (±pe±re)+cr±rp±dt±(ae/he)±tg±ff±hw
Behavioural activation (BA)† pl (±pe±re)+ba±rp±dt±(ae/he)±tg±ff±hw
Problem-solving therapy† pl (±pe±re)+ps±rp±dt± (ae/he)±tg±ff±hw
Assertiveness training† pl (±pe±re)+at±rp±dt±(ae/he)±tg±ff±hw
Cognitive-behavioural therapy (CBT)† pl (±pe±re)+cr+(ba±ps±at±bi)±rp±dt±(ae/he)±tg± ff±hw
Third-wave CBT (3W)† pl (±pe±re±cr±ba±ps±at±bi)+3w±rp±dt±(ae/he)±tg±ff±hw
  • *TAU here must include pharmacotherapy. Watchful waiting or follow-up by community nurses will therefore be classified as APP even when it is ‘treatment as usual’ in some settings.

  • †Any of these active interventions may be provided with or without TAU.

  • 3W, third-wave components; ae, automated encouragement to proceed with iCBT; bi, behaviour therapy for insomnia; cr, cognitive restructuring; dt, conventional drug treatment; ff, initial face-to-face contact; he, human encouragement to proceed with iCBT; hw, homework required; iCBT, internet-delivered cognitive–behavioural therapy; is, interpersonal skill training; pe, psychoeducation about depression; pl, placebo effect; ps, problem solving; re, relaxation; rp, relapse prevention; tg, therapeutic guidance for iCBT; w, waiting component.