Patient-Reported Outcome Instruments for Physical Symptoms Among Patients Receiving Maintenance Dialysis: A Systematic Review

Background: Patients with end-stage renal disease (ESRD) receiving dialysis have poor health-related quality of life. Physical symptoms are highly prevalent among dialysis-dependent patients and play important roles in health-related quality of life. A range of symptom assessment tools have been used in dialysis-dependent patients, but there has been no previous systematic assessment of the existing symptom measures' content, validity, and reliability.

Study Design: Systematic review of the literature.

Settings & Population: Patients with ESRD on maintenance dialysis therapy.

Selection Criteria For Studies: Instruments with 3 or more physical symptoms previously used in dialysis-dependent patients and evidence of validity or reliability testing.

Intervention: Patient-reported physical symptom assessment instrument.

Outcomes: Instrument symptom-related content, validity, and reliability.

Results: From 3,148 screened abstracts, 89 full-text articles were eligible for review. After article exclusion and further article identification by reference reviews, 58 articles on 23 symptom assessment instruments with documented reliability or validity testing were identified. Of the assessment instruments, 43.5% were generic and 56.5% were ESRD specific. Symptoms most frequently assessed were fatigue, shortness of breath, insomnia, nausea and vomiting, and appetite. Instruments varied widely in respondent time burden, recall period, and symptom attributes. Few instruments considered recall periods less than 2 weeks and few assessed a range of symptom attributes. Psychometric testing was completed for congruent validity (70%), known-group validity (25%), responsiveness (30%), internal consistency (78%), and test-retest reliability (65%). Content validity was assessed in dialysis populations in 57% of the 23 instruments.

Limitations: Consideration of physical symptoms only and exclusion of single symptom-focused instruments.

Conclusions: The number of available instruments focused exclusively on physical symptoms in dialysis patients is limited. Few symptom-containing instruments have short recall periods, assess diverse symptom attributes, and have undergone comprehensive psychometric testing. Improved symptom-focused assessment tools are needed to improve symptom evaluation and symptom responsiveness to intervention among dialysis-dependent patients.