Characteristics of included systematic reviews and meta-analysis
| Characteristic | Form response | N (%) |
| Journal in which systematic reviews were published (n=127) | Addiction | 30 (23.6) |
| Drug and Alcohol Dependance | 18 (14.2) | |
| Addictive Behaviors | 14 (11.0) | |
| Journal of Substance Abuse Treatment | 14 (11.0) | |
| Nicotine and Tobacco Research | 12 (9.4) | |
| Alcohol and Alcoholism | 6 (4.7) | |
| Other* | 33 (26.0) | |
| Conflict of interest (COI) statement (n=127) | All authors report no COI | 81 (63.8) |
| No COI statement present | 18 (14.1) | |
| One or more authors report a COI | 28 (22.0) | |
| Intervention type (n=127) | Pharmacologic | 64 (50.4) |
| Procedure | 2 (1.6) | |
| Behavioural therapy/psychosocial treatments | 53 (41.7) | |
| Prevention | 8 (6.3) | |
| Affiliation of first author (n=127) | Public academic institution | 92 (72.4) |
| Private academic institution | 15 (11.8) | |
| Government | 14 (11.0) | |
| Public academic institution, government | 1 (0.8) | |
| Non-profit institution | 4 (3.1) | |
| Private-for-profit | 1 (0.8) | |
| Affiliation of last author (n=127) | Public academic institution | 94 (74.0) |
| Private academic institution | 15 (11.8) | |
| Government | 13 (10.2) | |
| Public academic institution, government | 1 (0.8) | |
| Non-profit institution | 3 (2.4) | |
| Private-for-profit | 1 (0.8) | |
| Author source of funding (n=127) | No funding received | 33 (26.0) |
| No statement listed | 19 (15.0) | |
| Private/industry | 2 (1.6) | |
| Public | 66 (52.0) | |
| University | 4 (3.1) | |
| Public and university | 3 (2.4) | |
| Self-citation of primary studies (n=127) | No, did not include self-cited primary studies | 109 (85.8) |
| Yes, included one or more self-cited primary studies | 18 (14.2) |