Sullivan 2009.

Methods	Study design: RCT Duration of study: 3 months
Participants	Country: USA Setting: multicentre Diagnostic criteria: HD patients Number: treatment group (145); control group (134) Mean age ± SD (years): treatment group (54 ± 13); control group (52 ± 13) Sex (M/F): treatment group (83/62); control group (88/46) Comorbidity: hyperphosphataemia
Interventions	Intervention A study coordinator provided approximately 30 minutes of education regarding phosphorus‐containing additives and provided each intervention participant with a small magnifier in a plastic case. The names of common phosphorus‐containing additives were printed on the case. The coordinator instructed participants to avoid purchasing any items whose ingredient lists include phosphorus‐containing additives. A handout that listed specific menu items to be avoided was also given because they contained phosphorus additives. The study coordinator telephoned intervention participants during the second month of the study to reinforce the instructions and to answer any questions. Control Participants continued to receive care from their dietitians and nephrologists. A study coordinator telephoned control participants during the second month of the study
Outcomes	Serum phosphorus (mg/dL)
Notes	Funding: "supported by grant DK51472 from the National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland, and by the Leonard C. Rosenberg Renal Research Foundation, Cleveland, Ohio. Role of the Sponsor: The funding organizations had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; or preparation, review, or approval of the manuscript."
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	a random number generator was used
Allocation concealment (selection bias)	Unclear risk	Not reported
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not reported
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not reported
Incomplete outcome data (attrition bias) All outcomes	Low risk	Missing outcome data had similar reasons and balanced in numbers across intervention groups. Multiple imputation was used to account for missing data.
Selective reporting (reporting bias)	Low risk	The published reports included all expected outcomes that were pre‐specified
Other bias	Unclear risk	Insufficient information to permit judgement

CKD ‐ chronic kidney disease; CrCl ‐ creatinine clearance; FGF‐23 fibroblast growth factor 23; HD ‐ haemodialysis; M/F ‐ male/female; PTH ‐ parathyroid hormone; RCT ‐ randomised controlled trial; SCr ‐ serum creatinine