Table 1.
Studies included in the review and meta-analysis by outcome.
| Study | Country | Study design | Age range | Setting | Outcome measure | Sample size | Cases | Main findings |
|---|---|---|---|---|---|---|---|---|
| Panel A. Studies reporting death by suicide | ||||||||
| Anzai T, 202046 | Japan | Observational | <19 | General population | Number of suicides from March to May | 2019: 21,192,500 2020: 20,872,500 |
2019: 212 2020: 197 |
Male: excess mortality was observed in May (0.6) and June (3.7). Female: excess mortality was observed in March (5.3) and June (12.6) |
| Charpignon ML, 202250 | USA | Observational | 10–19 | General population | Annual number of suicides | 2019: 41,852,838 2020: 41,715,352 |
2019: 2755 2020: 2806 |
|
| Ehlman DC, 202249 | USA | Observational | 10–14 | General population | Annual number of suicides | 2019: 20,538,461 2020: 20,750,000 |
2019: 534 2020: 581 |
|
| Isumi A, 202032 | Japan | Observational | <19 | General population | IRR comparing the number of events from March to May in 2020 and in 2018–2019 | NA | NA | The event rate significantly increased in May (IRR: 1.34, 95% CI 1.01–1.78) compared to March |
| Matsumoto R, 202148 | Japan | Observational | <19 | General population | Annual number of suicides (first 6 months of 2021) | 2019: 21,691,777 2020: 21,404,883 2021: 21,037,601 |
2019: 21,691,777 2020: 21,404,883 2021: 404 |
|
| Tanaka T, 202147 | Japan | Observational | <19 | General population | Number of suicides February–June and July–October | Feb–Jun 2019: Jul–Oct 2019: Feb–Jun 2020: Jul–Oct 2020: |
Feb–Jun 2019: Jul–Oct 2019: Feb–Jun 2020: Jul–Oct 2020: |
IRR first wave (February–June): 0.98, 95% CI: 0.75–1.27 IRR second wave (July–October): 1.49, 95% CI: 1.12–1.98 |
| Panel B. Studies reporting prevalence data of suicidal behaviors | ||||||||
| Bukuluki P, 202151 | Uganda | Cross-sectional | 13–19 | General population | Prevalence within the past 6 months (structured interview in August 2020) | 219 | 53 | The prevalence within the past 6 months preceding the survey was 24.2% (95% CI: 18.7–30.4) |
| Carison A, 202152 | Australia | Observational | 7–18 | ED | Prevalence (time-period: April–September) | 2019: 18,935 2020: 11,235 |
2019: 313 2020: 515 |
|
| Psychiatric setting | 2019: 809 2020: 1190 |
2019: 313 2020: 515 |
||||||
| Díaz de Neira M, 202153 | Spain | Cross-sectional | 0–17 | Psychiatric setting | Prevalence (time-period: 11th March–11th April) | 2019: 95 2020: 43 |
2019: 15 2020: 10 |
|
| Ferrando SJ, 202154 | USA | Observational | NA | Psychiatric setting | Prevalence (time-period: January–February 2020 , March–April 2020) | Jan–Feb: 202 Mar–Apr: 65 |
Jan–Feb: 36 Mar–Apr: 13 |
|
| Fidancı I, 202155 | Turkey | Cross-sectional | 0–18 | ED | Prevalence (time-period: April–October) | 2019: 55,678 2020: 19,061 |
2019: 187 2020: 31 |
|
| Gatta M, 202256 | Italy | Observational | 0–17 | Psychiatric setting | Prevalence (time-period: February–March) | 2019–2020: 102 2020–2021: 96 |
2019–2020: 25 2020–2021: 18 |
|
| Gorny M, 202157 | UK | Observational | 0–18 | Psychiatric setting | Prevalence (time-period: March–May 2020) | 39 | 17 | |
| Gracia R, 202158 | Spain | Observational | 12–18 | General population | Prevalence (time-period: March–March) | 2019: 835,030 2020: 835,430 |
2019: 552 2020: 690 |
|
| Habu H, 202159 | Japan | Observational | NA | ED | Prevalence (time-period: March–August) | 2019: 1136 2020: 685 |
2019: 1 2020: 2 |
|
| Hou T, 202060 | China | Cross-sectional | Senior high school students | General population | Prevalence within the past 2 weeks (structured interview) | 859 | 64 | |
| Hou T, 202161 | China | Cross-sectional | 15–17 | General population | Prevalence within the past 2 weeks (structured interview in August 2020) | 761 | 79 | |
| Ibeziako P, 202262 | USA | Observational | 4–18 | Psychiatric setting | Prevalence (time-period: March 2019–February 2020, March 2020–February 2021) | 2019–2020: 2020 2020–2021: 1799 |
2019–2020: 236 2020–2021: 369 |
|
| Jones SA, 202263 | USA | Cross-sectional | 14–18 | General population | Prevalence within the past 12 months (January–June 2021) | 7705 | 693 | |
| Kirič B, 202264 | Slovenia | Observational | 6–19 | Psychiatric setting | Prevalence (time-period: March 2019–February 2020, March 2020–July 2021) | 2019–2020: 784 2020–2021: 1191 |
2019–2020: 67 2020–2021: 160 |
|
| Koenig J, 202165 | Germany | Observational | 12–18 | General population | Prevalence within the past 2 weeks (structured interview, before and after March 2020, matching subjects in the two periods on age, sex and type of school) | Before March 2020: 324 March–August 2020: 324 |
Before March 2020: 1 March–August 2020: 1 |
|
| Kose S, 202166 | Turkey | Observational | <18 | Psychiatric setting | Prevalence (time-period: 11th March–11th June 2019, 11th March–11th June 2020) | 2019: 128 2020: 66 |
2019: 31 2020: 14 |
|
| Llorca-Bofí V, 202267 | Spain | Observational | <18 | Psychiatric setting | Prevalence (time-period: January–March 2020, March–June 2020, October 2020–May 2021) | Jan–Mar 2020: 46 Mar–Jun 2020: 51 Oct 2020–May 2021: 245 |
Mar–Jun 2020: 9 Mar–Jun 2020: 6 Oct 2020–May 2021: 31 |
|
| McLoughlin A, 202268 | Ireland | Observational | <18 | Psychiatric setting | Prevalence (time-period: March–May) | 2019: 15 2020: 23 2021: 47 |
2019: 8 2020: 9 2021: 24 |
|
| Miles J, 202169 | USA | Observational | 2–18 | Psychiatric setting | Prevalence (time-period: January–December 2019, January–December 2020) | 2019: 1380 2020: 1380 |
2019: 538 2020: 239 |
|
| Millner AJ, 202270 | USA | Observational | 12–19 | Psychiatric setting | Prevalence within the past month (time-period: March 2017–March 2020, March 2020–March 2021) | 2017–2020: 1096 2020–2021: 275 |
2017–2020: 318 2020–2021: 139 |
|
| Mohd Fadhli SA, 202271 | Malaysia | Cross-sectional | 13–17 | General population | Prevalence within the past 12 months (online survey, time-period: May–September 2021) | 1290 | 108 | |
| Murata S, 202172 | USA | Cross-sectional | 13–18 | General population | Prevalence (online survey, time-period: April–July 2020) | 583 | 8 | |
| Ridout KK, 202173 | USA | Cross-sectional | 5–17 | ED | Prevalence (time-period: 10th March–15th December 2019, 10th March–15th December 2020) | 2019: 104,293 2020: 48,207 |
2019: 699 2020: 868 |
|
| Rømer TB, 202174 | Denmark | Observational | 0–17 | Psychiatric setting | Prevalence (time-period: January–December 2019, January 2020–February 2021) | 2019: 768 2020: 1133 |
2019: 295 2020: 406 |
|
| Sevecke K, 202275 | Germany | Observational | 6–18 | Psychiatric setting | Prevalence (time-period: January–December 2020, January–December 2021) | 2020: 383 2021: 538 |
2020: 112 2021: 158 |
|
| Zhang L, 202076 | China | Longitudinal cohort study | 9–16 | General population | Prevalence within the past 3 months (structured questionnaire in November 2019 and in May 2020) | 2019: 1271 2020: 1241 |
2019: 38 2020: 79 |
|
| Panel C. Studies reporting prevalence data of suicidal ideation | ||||||||
| Berger G, 202277 | Switzerland | Observational | <18 | Psychiatric setting | Prevalence (time period: March–April) | 2019: 109 2020: 86 2021: 164 |
2019: 74 2020: 62 2021: 137 |
|
| Bukuluki P, 202151 | Uganda | Cross-sectional | 13–19 | General population | Prevalence within the past 4 months (structured interview in August 2020) | 219 | 67 | |
| Cai H, 202278 | China | Cross-sectional | 10–19 | General population | Prevalence (online survey, study period: August 2020–March 2021) | 1057 | 125 | |
| Chadi N, 202179 | Canada | Observational | 12–17 | ED | Prevalence (time-period: January–December) | 2018–2019: 24,824 2020: 18,988 |
2018–2019: 1180 2020: 1073 |
|
| Psychiatric setting | 2018–2019: 2355 2020: 2201 |
2018–2019: 1180 2020: 1073 |
||||||
| Cordeiro F, 202180 | Portugal | Observational | NA | Psychiatric setting | Prevalence (time-period: March–June) | 2019: 178 2020: 59 |
2019: 31 2020: 10 |
|
| Davico C, 202181 | Italy | Observational | <18 | ED | Prevalence (time-period: 7 weeks before–8 weeks after lockdown (24th February 2020)) | Before 24th Feb: 10,888 After 24th Feb: 3395 |
Before 24th Feb: 18 After 24th Feb: 9 |
|
| Psychiatric setting | Before 24th Feb: 93 After 24th Feb: 50 |
Before 24th Feb: 18 After 24th Feb: 9 |
||||||
| Díaz de Neira M, 202153 | Spain | Cross-sectional | 0–17 | Psychiatric setting | Prevalence (time-period: 11th March–11th April) | 2019: 95 2020: 43 |
2019: 31 2020: 24 |
|
| Ferrando SJ, 202154 | USA | Observational | NA | Psychiatric setting | Prevalence (time-period: January–February 2020, March–April 2020) | Jan–Feb: 202 Mar–Apr: 65 |
Jan–Feb: 93 Mar–Apr: 28 |
|
| Fogarty A, 202282 | Australia | Cross-sectional | 14–17 | General population | Prevalence within the past 2 weeks (online survey, time period: June–September 2020) | 257 | 54 | |
| Gatta M, 202256 | Italy | Observational | 0–17 | Psychiatric setting | Prevalence (time-period: February–March) | 2019–2020: 102 2020–2021: 96 |
2019–2020: 46 2020–2021: 52 |
|
| Hou T, 202060 | China | Cross-sectional | 15–17 | General population | Prevalence within the past 2 weeks (structured interview) | 859 | 269 | |
| Hou T, 202161 | China | Cross-sectional | 15–17 | General population | Prevalence within the past 2 weeks (structured interview in August 2020) | 761 | 277 | |
| Ibeziako P, 202262 | USA | Observational | 4–18 | Psychiatric setting | Prevalence (time-period: March 2019–February 2020, March 2020–February 2021) | 2019–2020: 2020 2020–2021: 1799 |
2019–2020: 1004 2020–2021: 1073 |
|
| Jones SE, 202263 | USA | Cross-sectional | 14–18 | General population | Prevalence within the past 12 months (January–June 2021) | 7705 | 1533 | |
| Kiric B, 202264 | Slovenia | Observational | 6–19 | Psychiatric setting | Prevalence (time-period: March 2019–February 2020, March 2020–July 2021) | 2019–2020: 784 2020–2021: 1191 |
2019–2020: 307 2020–2021: 537 |
|
| Koenig J, 202165 | Germany | Observational | 12–18 | General population | Prevalence within the past 2 weeks (structured interview, before and after March 2020, matching subjects in the two periods on age, sex and type of school) | Before March 2020: 324 March–August 2020: 324 |
Before March 2020: 44 March–August 2020: 33 |
|
| Kose S, 202166 | Turkey | Observational | <18 | Psychiatric setting | Prevalence (time-period: 11th March–11th June 2019, 11th March–11th June 2020) | 2019: 128 2020: 66 |
2019: 42 2020: 15 |
|
| Liu Y, 202183 | China | Cross-sectional | 9–18 | General population | Prevalence within the past 2 weeks (structured questionnaire administered in June 2020) | 5175 | 155 | |
| Llorca-Bofí V, 202267 | Spain | Observational | <18 | Psychiatric setting | Prevalence (time-period: January–March 2020, March–June 2020, October 2020–May 2021) | Jan–Mar 2020: 46 Mar–Jun 2020: 51 Oct 2020–May 2021: 245 |
Mar–Jun 2020: 11 Mar–Jun 2020: 15 Oct 2020–May 2021: 65 |
|
| McLoughlin A, 202268 | Ireland | Observational | <18 | Psychiatric setting | Prevalence (time-period: March–May) | 2019: 15 2020: 23 2021: 47 |
2019: 13 2020: 13 2021: 40 |
|
| Miles J, 202169 | USA | Observational | 2–18 | Psychiatric setting | Prevalence (time-period: January–December 2019, January–December 2020) | 2019: 1380 2020: 1380 |
2019: 655 2020: 277 |
|
| Millner AJ, 202270 | USA | Observational | 12–19 | Psychiatric setting | Prevalence within the past month (time-period: March 2017–March 2020) | 2017–2020: 1096 2020–2021: 275 |
2017–2020: 827 2020–2021: 227 |
|
| Mohd Fadhli SA, 202271 | Malaysia | Cross-sectional | 13–17 | General population | Prevalence within the past 12 months (online survey, time-period: May–September 2021) | 1290 | 154 | |
| Murata S, 202172 | USA | Cross-sectional | 13–18 | General population | Prevalence (online survey, time-period: April–July 2020) | 583 | 156 | |
| Peng X, 202284 | China | Cross-sectional | 12–18 | General population | Prevalence within the past 2 weeks (April 2020) | 39,751 | 8069 | |
| Ridout KK, 202173 | USA | Cross-sectional | 5–17 | ED | Prevalence (time-period: 10th March–15th December 2019, 10th March–15th December 2020) | 2019: 104,293 2020: 48,207 |
2019: 2688 2020: 2481 |
|
| Sevecke K, 202275 | Germany | Observational | 6–18 | Psychiatric setting | Prevalence (time-period: January–December 2020, January–December 2021) | 2020: 383 2021: 538 |
2020: 187 2021: 264 |
|
| Shanmugavadivel D, 202185 | UK | Observational | 0–18 | ED | Prevalence (time-period: March–May) | 2019: 8813 2020: 4417 |
2019: 111 2020: 54 |
|
| She R, 202286 | China | Cross-sectional | 12–15 | General population | Prevalence within the past 2 weeks (time-period: September–November 2020) | 3080 | 918 | |
| Turner BJ, 202187 | Canada | Cross-sectional | 12–18 | General population | Prevalence within the past 4 months (structured questionnaire administered between June and July 2020) | 809 | 352 | |
| Zalsman G, 202188 | Israel | Observational | 10–17 | Psychiatric setting | Prevalence (time-period: January–June) | 2019: 1235 2020: 1598 |
2019: 246 2020: 250 |
|
| Zhang L, 202076 | China | Longitudinal cohort study | 9–16 | General population | Prevalence within the past 3 months (structured questionnaire administered in November 2019 and in May 2020) | 2019: 1271 2020: 1241 |
2019: 286 2020: 369 |
|
| Zhang Y, 202289 | China | Cross-sectional | 9–19 | General population | Prevalence within the past 2 weeks (online survey in February 2020) | 3471 | 115 | |
| Zhu S, 202190 | China | Longitudinal cohort study | 10–17 | General population | Prevalence within the past 2 weeks (structured questionnaire administered in September 2019 and in June 2020) | 2019: 1381 2020: 1381 |
2019: 336 2020: 291 |
|
| Zhu J, 202291 | China | Cross-sectional | 9–19 | General population | Prevalence during COVID-19 lockdown period (online survey in June 2020) | 5175 | 155 | |
Abbreviation: ED, emergency departments.