We conducted a three-wave longitudinal and a diary study simultaneously measuring different antecedents for perpetration. The results of the first wave longitudinal study (LS) (N = 2508) were used to recruit participants and to set control variables for the diary study. For the LS, we collected data mainly by reaching out to two psychology and organizational psychology professors at Spanish and Turkish universities. We invited them to help in the initial wave data-gathering phase by encouraging their students to find respondents who worked at least eight hours per week, in line with the ILO definition of being employed [47], in exchange for extra credit. Data obtained by students gathering respondents were heterogeneous and thus more likely to be generalizable [48]. Respondents were informed that the study was about employee health without explaining the hypotheses and disguising that it was a study on WB. Data were collected via the Qualtrics survey tool. The study was conducted under the approval of the Bioethical Committee of the University of Barcelona covering the countries mentioned (protocol code IRB00003099, approved as of 5 October 2020). All respondents provided electronic informed consent to participate, their data to be used for publication and entered their email addresses to be further contacted for research.The following criteria were used to invite first-wave respondents to the diary study (i) bullies and perpetrators, (ii) victims and targets, since being a target strongly predicts being a perpetrator, (iii) participants high in neuroticism, low in agreeableness and conscientiousness as these traits are related to WB bullying and perpetration. Therefore, from the LS T1 results, employees with higher-than-average perpetration (M = 1.22, SD = .57), target (M = 1.66, SD = .91), victim (M = 1.47, SD = 1.15), and bullying scores (M = 1.14, SD = .66) were invited to the diary study. Additionally, employees with lower-than-average conscientiousness (M = 5.43, SD = 1.17), agreeableness (M = 5.52, SD = 1.05), and higher-than-average neuroticism (M = 3.74, SD = 1.15) traits were also invited to join the diary study. Therefore, 493 participants were invited to the study disguised as wellness training called the “Leadership Wellness Program”. Thirty-eight individuals adhering to our inclusion criteria and who were currently working joined the diary study. Seven participants reported no perpetration during the diary study. Therefore, they were taken out from the analysis leaving a total of 31 participants (Table 1). All the analyses conducted on the within-level were based on the 31 participants involved in WB perpetration during the diary study, while between-level analysis is based on their scores at the first wave of LS. The second (T2) and third waves (T3) of the LS are not part of the present study.

The participants provided 720 observations, where 28 participants completed 24 waves, one participant 19 waves, one participant 15 waves and one participant 14 waves of data collection. We observed WB perpetration 720 times of the possible 912 (24 weeks × 38 participants), yielding an observation rate of 78.95%.

Their average age was 37.94 (SD = 12.27), with 6.39 years of tenure in work-life. On average, they worked 5.10 days (SD = .70) weekly. Participants had various professions (e.g., academicians, customer support and sales representatives, finance managers, medical doctors, graphic designers, human resources professionals, IT managers, municipality administration officials, and teachers). They were from various sectors: manufacturing (16.67%), wholesale and retail trade (16.67%), information and communication (16.67%), education (13.33%), health (10.00%), and other sectors (20.00%). Of the 31 participants, only four participants (12.90%) worked in a gender-balanced environment, twelve (38.71%) were supervisors, and eighteen (58.06%) were living in Turkey. Fourteen participants (45.16%) were female, and 9 (29.03%) reported having or had been diagnosed with a mental illness (Mental Illness score was formed by (i) asking for a “yes = 1” or “no = 0” answer to; “Has a physician ever informed you that you have or have had chronic diseases listed below?” Depression [49]. (ii) Open-ended question on other chronic illnesses. Then, mental illnesses mentioned (e.g., bipolar disorder, obsessive-compulsive disorder) were scored as “yes = 1” in the other mental illnesses column. Finally, depression scores and other mental illnesses columns were combined to form “mental illnesses”). Participants were not subject to COVID-19 lockdown measures. Based on the first wave of LS, they scored 4.05 (SD = 1.17) on extraversion (Personality traits were measured using the 20-item mini-IPIP scale [50], (1 = completely false, 7= completely true)), 5.65 (SD = .83) on agreeableness, 5.21 (SD = 1.15) on conscientiousness, 4.35 (SD = 1.30) on neuroticism, 4.92 (SD = 1.14) on intelligence and imagination. They reported that they were victims of bullying (T1 Victim score was measured by single-item questions with a bullying definition (COPSOQ III); “Bullying means that a person repeatedly is exposed to unpleasant or degrading treatment, and that the person finds it difficult to defend himself or herself against it”. Have you been exposed to bullying at your workplace in the last 6 months? (1 = never, 7 = very frequently) [51]). (M = 2.16, SD = 1.70), and they bullied others (T1 Bully question was obtained by modifying the bullying questions into an active form; “Have you bullied others at your workplace in the last 6 months? (1 = never, 7 = very frequently).) in their current jobs (M = 1.32, SD = 1.14). We also inquired about bullying experiences and WB perpetration through a behavioral approach. The participants scored 2.28 (SD = .86) on target questions (Workplace bullying was measured by a 4-item EAPA-T-R scale [52] (1 = never, 7 = very frequently/more than once a week). Workplace bullying perpetration was measured by the same scale by adopting the questions to an active format), 1.30 (SD = .39) on WB perpetration, 3.97 (SD = 1.49) on organizational trust (Organizational Trust was measured by a 7-item scale [53] (1 = strongly disagree, 7 = strongly agree)), 3.73 (SD = 1.58) on organizational justice (Organizational Justice was measured by a 6-item scale [54] (1 = strongly disagree, 7 = strongly agree)), 3.11 (SD = 1.49) on psychological distress (Psychological Distress was measured by a 4-item scale [55] (1 = never, 7 = always)) and 2.61 (SD = .77) on physical symptoms (Physical Symptoms were measured by the 12-item version [56] (1 = never, 7 = always)).