Table 1. Summary of included studies (full details in online supplemental table S4).
| Author | Category: number and type of interventions included | Summary of study countries and income level | Study outcome measure/s | Main risk estimate from meta-analysis | Events in non-intervention group | Events in intervention group |
|---|---|---|---|---|---|---|
| Okolie et al36 | Roads: no eligible studies | NA | NA | NA | NA | NA |
| Okolie et al16 | Jumping: 14 studies of means restrictions at bridges and other jumping sites | Switzerland (3) USA (3), UK (2), Canada (2), New Zealand (2) and Australia (2). All high-income countries. | Number of suicide deaths (13 studies), suicide attempts (1) | Suicide deaths: IRR 0.09 (0.03 to 0.27), p<0.001. | 742.3 suicide deaths per year | 70.6 suicide deaths per year |
| Pirkis et al2 | Jumping: 9 studies of 8 structural interventions on bridges and cliffs | UK (2), USA (2), New Zealand (2), Canada (1), Switzerland (1). All high-income countries. | Numbers and rates of suicide deaths. | Suicide deaths: RR 0.14, 95% CI 0.09 to 0.21, p=0.001. | 436 (5.7 per year) | 21 (0.5 per year) |
| Barker et al21 | Railway: 5 articles of means restriction measures at railway stations. | Hong Kong (2), Japan (1). All high-income countries. | Number of suicide deaths (6), fatality rate of suicide attempts (2), suicide attempts (2). | Meta-analysis was not conducted. | Not available | Not available |
| Lim et al27 | Poisoning (multiple): 62 studies of pesticides (23 studies), domestic gas (17), motor vehicle exhaust (11) and pharmaceuticals (11). | 26 countries: 20 high-income countries (53 studies) and 6 low- and middle-income countries (9 studies). | Change in rate of suicide deaths using the restricted poison, measured using IRR. | Meta-analysis was not conducted. | Not available | Not available |
| Morgan et al28 | Paracetamol poisoning: 12 studies examining restrictions of paracetamol. | All 12 studies were of the UK (high-income). | Severity of poisoning (8 studies), hospital admission (6) and deaths from paracetamol poisoning (3). | Meta-analysis was not conducted. | Not available | Not available |
| Gunnell et al4 | Pesticides: 27 studies of specific pesticides bans (12 studies), sales restrictions (8) and mandatory licensing or registering of users (5). | 16 countries. 5 low-income or middle-income countries (Bangladesh, Colombia, India, Jordan and Sri Lanka) and 11 high-income (Denmark, Finland, Germany, Greece, Hungary, Ireland, Japan, South Korea, Taiwan, UK and USA). | Rates and numbers of pesticide suicide deaths. | Meta-analysis was not conducted. | Not available | Not available |
| Reifels et al30 | Pesticides: 5 studies. | 3 studies in India and 2 in Sri Lanka. All lower- and middle-income countries. | Rates of suicide (4), suicide from pesticide poisoning (2) and attempted suicide (3). | Meta-analysis was not conducted. | Not available | Not available |
| Pirkis et al17 | Jumping: 23 articles representing 18 unique studies of jumping. | USA (5), UK (3), NZ (2), Australia (2), Canada (2), Hong Kong (2), Switzerland (2). All high-income countries. | Suicide rates | Suicide deaths: IRR 0.07, 95% CI 0.02 to 0.19, p<0·0001. | 863 (5.8 per year) | 211 (2.4 per year) |
| Cox et al22 | Jumping: 9 studies of restricting access to means by installing physical barriers at sites used for jumping. | UK (2), Hong Kong (1), New Zealand (2), USA (2), Switzerland (1), Canada (1). All high-income countries. | Numbers of suicide deaths. | Meta-analysis was not conducted. | Not available | Not available |
| Linskens et al19 | Multiple: 10 studies of 9 interventions including 4 studies of barriers at bridges or railway stations, 3 of platform screen doors and 3 of restricting access to charcoal. | Hong Kong (2), South Korea (2), Taiwan, Canada, Australia, Switzerland, Japan. All high-income countries. | Suicide deaths (including method-specific) per year. | Meta-analysis was not conducted. | Not available | Not available |
| Ishimo et al20 | Multiple: 11 studies on physical barriers, 3 studies on pesticides restrictions, 4 studies on domestic gas, motor vehicle gas and charcoal poisoning. | 3 studies (of 2 interventions) in Canada, Japan (3 studies), New Zealand (2), Switzerland (2), South Korea (1), UK (1) Australia (1). All high-income countries. | Suicide mortality rates and site/method-specific suicide deaths. | Meta-analysis was not conducted. | Not available | Not available |
| Zalsman et al23 | Multiple: 24 studies of firearms restrictions (11), medication withdrawal (5), pesticide restriction (5), barriers at jumping sites (2) and charcoal sales restrictions (1). | USA (4), Australia (2), UK (3), Sri Lanka (3), India (1), Norway (1), Sweden (1), Denmark (1), Switzerland (1), Israel (1), New Zealand (1), Austria (1), Canada (1), Hong Kong (1). 4/24 studies in lower- and middle-income countries. | Suicide death, including methods-specific death. | Meta-analysis was not conducted. | Not available | Not available |
| Mann et al24 | Multiple: 27 studies of barbiturate restrictions (7), firearms restrictions (6), domestic gas detoxification (6), catalytic converters (4), pesticide restrictions (2), barriers to jumping (1), analgesic pack size change (1). | USA (5), Canada (3), Australia (4), Finland (1), Samoa (1), UK (5), Japan (1), New Zealand (1), Germany (1), Norway (1), Sweden (1), Netherlands (1), Denmark (1). One upper-middle income country. | Suicide deaths. | Meta-analysis was not conducted. | Not available | Not available |
| Mann et al31 | Multiple: 49 studies of firearms restrictions, 2 studies of pesticides, 3 studies of domestic and motor vehicle gas. | List of included studies not available. | Suicide deaths. | Meta-analysis was not conducted. | Not available | Not available |
| Robinson et al29 | Multiple: 8 studies on means restriction (2 on restriction of SSRIs in under 18 s and 6 on firearms restrictions). | Canada (3), New Zealand (1), Israel (1), Austria (1), UK (1). One study of 23 WHO Stratum A countries. | All suicide deaths, method-specific suicide. | Meta-analysis not conducted. | Not available | Not available |
| Bailey et al32 | Pesticides (1). | Sri Lanka (1). Lower-middle-income country. | Pesticide self-poisoning. | Meta-analysis was not conducted. | Not available | Not available |
| Hahn et al34 | Firearms: 15 studies of firearms restrictions. | USA (14) and Canada (2). High income countries. | Suicide deaths. | Meta-analysis was not conducted. | Not available | Not available |
| National Institute for Health and Care Excellence18 | Multiple: 16 studies of barriers and safety nets at jumping sites (11), platform screen doors (2), road access restriction (2) and firearm legislation (1). | Canada (2), USA (3), New Zealand (2), Switzerland (1), UK (2), Austria (1), Australia (3), South Korea (1), Japan (1). All high-income countries. | Suicide deaths and suicide attempts. | Suicide deaths: risk ratio=0.24 (95% CI 0.14 to 0.39). | 1001 (3.16 per year) | 116 (0.72 per year) |
| Rubbo et al33 | Pesticides: 9 studies of pesticide regulations. | India (2), South Korea (2), Taiwan (2), Japan (1), China (1), Mongolia (1). 4/9 studies were in lower- and middle-income countries. | Suicides by pesticide poisoning. | Meta-analysis was not conducted. | Not available | Not available |
IRR, incident rate ratio.