Ahmady 2019.

Study characteristics
Methods	Study design Parallel RCT Study dates Duration of follow‐up: 14 days Study duration: December 2016 to August 2017
Participants	Study characteristics Setting: single centre (Imam Reza Hospital based in Kermanshah) Country: Iran Inclusion criteria: history of HD for at least 6 months; 18 to 65 years; ability to communicate verbally; not being allergic to the smells of lavender and orange; lack of respiratory diseases such as asthma; having a healthy sense of smell (through patient statements and nasal examination for no obstruction); being a non‐candidate for kidney transplantation; not pregnant (for women); having no addiction Exclusion criteria: patients who were not interested in continuing the study and being absent for more than 3 consecutive sessions at the time of intervention Baseline characteristics Number (analysed/randomised): intervention group 1 (30/30); intervention group 2 (30/30); control group (30/30) Mean age ± SD (years): overall (55.25 ± 11.79) Sex (M/F): intervention group 1 (16/14); intervention group 2 (16/14); control group (9/21) Dialysis type: HD Mean dialysis vintage ± SD (years): overall (4.1 ± 0.4) Comorbidities CVD: not reported Diabetes: intervention group 1 (12/18); intervention group 2 (8/22); control group (12/18) Hypertension: not reported Depression (clinician diagnosis): not reported
Interventions	Intervention classification Non‐pharmacological intervention Indication: study targeting fatigue Intervention group 1 Aromatherapy with 5 drops of lavender essential oil Intervention group 2 Aromatherapy with 5 drops of orange essential oil Control group Placebo: 5 drops of distilling water Co‐interventions Not reported
Outcomes	Outcomes reported Fatigue outcome measures used: validation data available Fatigue: FSS (Appendix 3) Death
Notes	Additional information Funding: Kermanshah University of Medical Sciences (Grant No. 95571) Conflicts of interest/disclosures: none Trial registration identification number: IRCT201610244736N17 A priori published protocol was reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Random block of numbers. Block randomisation was conducted as follows: the group of aromatherapy with lavender essential oil was given the code “A,” the group of aromatherapy with orange essential oil was given the code “B,” and the group of distilled water was given the code “C.” Then, six blocks of three were formed: ABC, ACB, BAC, BCA, CAB, and CBA. In order to select the groups, block BAC was randomly selected. Thus, on the first day (which was Saturday), 30 subjects were assigned to the group of aromatherapy with orange essential oil. On Sunday, 30 subjects were assigned to lavender essential oil group and finally on Monday, another 30 subjects were assigned to the control group." Comment: random numbers are considered at low risk of bias
Allocation concealment (selection bias)	Low risk	Quote: "The names of subjects in each group were registered in the coming days. The statistical adviser of the study (second author) was responsible for determining the blocks, and the subjects were allocated into the study groups by the first author."
Blinding of participants and personnel (performance bias) All outcomes	High risk	Quote: "There was no possibility of blinding subjects for the type of the assigned group."
Blinding of outcome assessment (detection bias) All outcomes	High risk	Fatigue was assessed with an appropriate measure, without differences between groups. However, subjective measures were used, it was not stated whether outcomes were assessed without knowledge of treatment allocation, and knowledge of treatment assignment may have influenced reporting. Participant beliefs about the superiority/inferiority of either intervention could have influenced their assessment of the outcome, but there was no evidence that this was likely. No other outcomes were assessed
Incomplete outcome data (attrition bias) All outcomes	Low risk	All participants completed the study. No lost to follow‐up were reported
Selective reporting (reporting bias)	High risk	Protocol was published. It was reported if multiple eligible outcome measurements (scales and time points) were pre‐specified. It was unclear if the reported approach to analysing this outcome was pre‐specified or influenced by the results. Fatigue data were cumulated for 2 RCTs, all time points were not reported. All outcomes that should be addressed (fatigue, cardiovascular disease, and death) were not reported
Other bias	Low risk	There was no evidence of different baseline characteristics, or different non‐randomised co‐interventions between groups. Funding did not influence the data analysis and conflicts of interest were not reported. No other source of bias were apparent