Table 1

Study characteristics

StudyTotal nTarget groupEligible age groupComparisoniCBT weeks (no of modules)Included measure of suicidal ideationDrop-out iCBT*Drop-out control*IPD
Batterham 201826 132†General population (young adults)18+ (initially 18–25)

  1. unguided iCBT (online)

  2. active online intervention

2 (10)SIDAS41 (62.1%)37 (56.1%)Yes
De Jaegere 201930 724General population (adults)18+

  1. unguided iCBT (online)

  2. waitlist

6 (6)BSS270 (74.0%)187 (52.1%)Yes
Eylem 202128 18Turkish migrants (adults)18+

  1. guided iCBT (online)

  2. waitlist

6 (6)BSS0 (0%)2 (25.0%)Yes
Hetrick 201725 50School students (adolescents)13–19

  1. guided iCBT (online)+TAU

  2. TAU

10 (8)SIQ8 (30.8%)3 (12.5%)No
Hill 201929 80General population (adolescents)13–19

  1. unguided iCBT (online)

  2. waitlist

2 (2)BSS5 (12.2%)4 (10.0%)Yes
Mühlmann 202127 402General population (adults)18+

  1. guided iCBT (online)

  2. waitlist

6 (6)BSS25 (12.8%)24 (11.7%)Yes
Tighe 201723 61Australian Indigenous youth (young adults)18+ (initially 18–35)

  1. unguided iCBT (App)

  2. waitlist

6 (3)DSI-SS2 (6.5%)0 (0%)Yes
Van Spijker 201416 236General population (adults)18+

  1. unguided iCBT (online)

  2. waitlist

6 (6)BSS11 (9.5%)10 (8.3%)Yes
Van Spijker 201831 418General population (adults)18–65

  1. unguided iCBT (online)

  2. active online intervention

6 (6)SIDAS98 (47.3%)94 (44.5%)Yes
Wilks 201832 59Heavy episodic drinkers (adults)18+

  1. guided iCBT (online)

  2. waitlist

8 (8)BSS8 (26.7%)1 (3.4%)Yes

  • *This refers to drop-out at postintervention as reported in the original trials.

  • †The total number of participants does not include the ineligible static intervention condition (third intervention arm with an additional n=62, excluded from our analyses).

  • BSS, Beck Scale for Suicidal Ideation; DSI-SS, Depressive Symptom Inventory-Suicidality Subscale; iCBT, interventions based on cognitive–behavioural therapy; SIDAS, Suicidal Ideation Attributes Scale; SIQ, Suicidal Ideation Questionnaire.