Behnammoghadam 2019.

Study characteristics
Methods	Study design: randomised controlled trial Study grouping: parallel group
Participants	Baseline characteristics Eye movement desensitisation and reprocessing (EMDR) Age in years (mean ± SD): 30.8 ± 5.5 Sex (N (% female)): NR Sample size: 25 Years of experience (mean ± SD): 7.5 ± 4.9 Control (no intervention) Age in years (mean ± SD): 31.5 ± 6.4 Sex (N (% female)): NR Sample size: 25 Years of experience (mean ± SD): 8.6 ±5.6 Overall Age in years (mean ± SD): 31.1 ± 5.9 Sex (N (% female)): NR Sample size: 50 Years of experience (mean ± SD): 5.2 ± 8 Included criteria: employed as one of the technician classes (rescuer, basic, middle, or senior technician) at pre‐hospital medical emergency services, age range 18–55 years, working at pre‐hospital medical emergency services as their main job, not employed in administrative departments or communication centre of pre‐hospital medical emergency services, no drug addiction, no hearing or vision impairment, and concurrently, getting scores above 19 in the Alken stress scale, and provided written informed consent to participate in the study. Excluded criteria: no motivation to cooperate, intolerance to the treatment, absent for more than one therapeutic session, imprecise completion of data collection instruments, transfer or death of the technician. Pretreatment: there were no significant differences between the two groups for age, years of experience and stress at baseline. Compliance rate: not able to assess as participants absent for more than one therapeutic session were excluded Response rate: not able to assess Type of healthcare worker: exclusively emergency medical technicians
Interventions	Intervention characteristics Eye movement densensitization and reprocessing (EMDR) Type of the intervention: Intervention type 1 ‐ to focus one’s attention on the experience of stress Description of the intervention: Subjects in the intervention group received EMDR training in five consecutive 45–90 sessions, as a research intervention based on the approved protocol, and according to the following eight stages: 1. History taking and treatment design: while communicating with the subject, the history was taken and the treatment process was designed. 2. Preparation: by describing the process, the subject was being prepared for EMDR implementation. 3. Evaluation: the subjects were asked to recall the problematic distressing events and measure their subjective units of disturbance using an 11‐degreemental disorder scale from 0 to 10. Zero means a lack of mental discomfort, and 10 means the maximum mental discomfort. Then, in a test to assess the validity of cognitions as one of the other pre‐test scales, they were asked to express their positive beliefs and rank it from 1 to 7 in a seven‐point scale. One means completely false and 7 means perfectly true. Then, after applying this technique, both of the scales were re‐evaluated. 4. Desensitisation: according to Shapiro, the inventor of this technique, at this stage the subject is asked to imagine the most prominent part of an annoying scene, focusing on the negative recognition of the scene that the subject previously described in a brief sentence expressing a harmful event such as “I am guilty“ or “it is really terrible or disturbing to me“to concentrate on emotions and physical states related to tension and anxiety, and then, after determining which part of the body is affected by the anxiety, the subject is instructed to follow the rapid movements of the therapist’s finger just about 30 cm away from his eyes, from right to left and vice versa, across his field of vision. This movement involves two rounds of trips to the sides within 1 second, which is considered a cycle, and each 24–24 cycles constitute a set. After each set, the researcher asks the subjects to stop imagining the scene, lean back into the back of their seat, and breathe deeply. Then, the level of mental discomfort and cognitive validity were ranked, evaluated, and recorded. This process, based on the need and motivation of the subjects, was continued until the level of mental discomfort reached 0 or minimum. 5. Implementation: the subjects were asked to recall the positive phrases and then repeat the eye movement process. 6. Physical scan: subjects were asked to focus on that part of the body that had difficulty during stress or anxiety, and evaluate the problem. 7. Completion: this step was to ensure the stability of the subjects at the end of the session. 8. Re‐evaluation: subjects again completed subjective units of disturbance and VOC scale. The number of sessions: 5 Duration of each session on average: NR Duration of the entire intervention: 5 days Duration of the entire intervention short vs long: Short Intervention deliverer: NR Intervention form: Individual Control (no intervention) Type of the intervention: NA Description of the intervention: NA The number of sessions: NA Duration of each session on average: NA Duration of the entire intervention: NA Duration of the entire intervention short vs long: NA Intervention deliverer: NA Intervention form: NA
Outcomes	Elkin stress symptoms scale Outcome type: ContinuousOutcome
Identification	Sponsorship source: NR Country: Iran Setting: Medical Emergency Services, urban and road stations Comments: NR Authors name: Sharif Shahini Institution: University of Medical Sciences, Next to Imam Sajad Hospital Email: sharif.shahini@yahoo.com Address: PO Box: 2591994 Yasuj, Iran Time period: 2017
Notes	Elkin stress symptoms scale included in analysis 1.1
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "A number was assigned to the subjects who concurrently got a score of above 19 in the SSS, and by matching that number with the block random allocation list, the technicians were assigned to the intervention or control group, and the process was continued until the completion of the estimated sample size."
Allocation concealment (selection bias)	Unclear risk	Quote: "25 people for each group. During random block assignment, the order of the participants in the intervention and control groups was determined as follows. By multiplying the number of study groups (two groups) by 2, the number of samples per block was calculated as 4; then, by calculating the factorial of each block sample size (4!=4×3×2×1=24), the number of blocks generated from all possible orders was obtained as 24; since the number of people in each block was 4 and the estimated sample size was 50 based on the following description, by matching 13 random numbers generated by Sample Randomizer with the mentioned block numbers, the order of 50 research subjects was determined, numbers 1–50 were allocated to the subject and control groups, and the random allocation list was edited." Difficult to judge whether participants and/or investigators could possibly foresee assignment
Blinding of participants and personnel (performance bias) All outcomes	High risk	Participants were not blinded.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Participants were not blinded whereas outcomes are self‐reported.
Incomplete outcome data (attrition bias) All outcomes	Low risk	No loss to follow‐up
Selective reporting (reporting bias)	Low risk	Quote: "Iranian Clinical Trial Registry Website (code: IRCT20180102038191N1)." Trial registration in which the stress scale is not specified. No indication of selective reporting.
Other bias	Unclear risk	Not able to assess compliance/as participants absent for more than one therapeutic session were excluded.