Barre 1988.

Study characteristics
Methods	Study design Cross‐over RCT Study dates Duration of follow‐up: 2 months (first period) (each patient was randomly assigned a dialysate for 1 month period over 6 months) Time frame: not reported
Participants	Study characteristics Setting: single centre Country: Canada Inclusion criteria: male patients undergoing HD Exclusion criteria: patients who took antihypertensive drugs Baseline characteristics Number (analysed/randomised): overall (not reported/5) Age range: overall (46 to 62) Sex (M/F): overall (5/0) Dialysis type: HD Dialysis vintage (years, range): overall (2.1 to 10) Comorbidities CVD: not reported Diabetes: not reported Hypertension: not reported Depression (clinician diagnosis): not reported
Interventions	Intervention classification Pharmacological intervention Indication: study reporting fatigue Intervention group 1 Dialysate containing 145 mEq/L of sodium for a 1‐month period Intervention group 2 Dialysate containing 150 mEq/L of sodium for a 1‐month period Intervention group 3 Dialysate containing 155 mEq/L of sodium for a 1‐month period Co‐interventions All patients were taking a magnesium‐containing phosphate binder (magaldrate) No changes were made in the dialysis therapy, diet, or medications
Outcomes	Outcomes reported Fatigue outcome measures used: validation data available (fatigue was reported as an adverse event) Vital signs (arterial BP while seated, pulse, dry weight, interdialytic weight gain, predialysis MAP): assessed before and after dialysis Adverse events (including fatigue) (reported using a self‐reported questionnaire for each dialysis): assessed for each dialysis Routine haematologic and biochemical data (change in serum sodium and magnesium levels): assessed before dialysis and at the end of each month
Notes	Additional information Funding: Erika (Rockleigh, Nj) Conflicts of interest/disclosures: not reported Trial registration identification number: not applicable A priori published protocol: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "Dialysis was performed in random sequence with dialysate sodium of 145, 150, or 155 mEq/L for 2 months at a time." Comment: Sequence generation methods were not reported in sufficient detail to permit judgement
Allocation concealment (selection bias)	Unclear risk	Quote: "The customise coded dialysis concentrates were provided by Erika (Rockleigh, Nj)." Comment: The sponsor performed the allocation. Not sure if they were unaware of treatment assigned
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Quote: "A double blind prospective study was carried out in five stable men on chronic haemodialysis." Comment: Although author reported that the study used a double‐blind design, information about blinding of participants and investigators were not clearly stated
Blinding of outcome assessment (detection bias) All outcomes	High risk	Quote: "Each patient completed a questionnaire for each dialysis and was asked to report symptoms during and between dialysis. These included thirst, nausea, vomiting, headache, weakness, restless, fatigue, itchiness, crams, or any other symptoms." Comment: The outcomes were assessed with an appropriate measure, without differences between groups. However, fatigue was assessed as an adverse event and it was not stated whether it was 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. However, objective and subjective outcomes were assessed
Incomplete outcome data (attrition bias) All outcomes	High risk	The number of patients who completed the study was not clearly stated for the first phase. It was unclear if there was evidence that the results were not biased by missing outcome data
Selective reporting (reporting bias)	High risk	Information about the protocol and the statistical analysis plan were not reported. It was unclear if the reported approach to analysing this outcome was pre‐specified or influenced by the results. Fatigue at the end of treatment was not reported in a format that was extractable for meta‐analysis (cross‐over study: data related to the first period were not reported). All outcomes that should be addressed (fatigue, cardiovascular disease, and death) were not reported
Other bias	High risk	No data were available to assess the possible imbalance between groups. Funding was likely to influence data analyses and interpretation and conflicts of interest were not reported