Development and Evaluation of a Scored Sodium Questionnaire-Screening Form for Kidney Disease Patients

Abstract

Objective: To develop and evaluate a screening version of the validated Scored Sodium Questionnaire (SSQ).

Design: Development phase—a Scored Sodium Questionnaire–Screening Form (SSQ-SF) and scoring system were developed using data previously collected in 47 chronic kidney disease outpatients participating in the SSQ validation study; evaluation phase—conducted in 49 participants with end-stage kidney disease on hemodialysis and 16 nursing staff.

Subjects: A total of 49 outpatients (61% male) aged 63.1 ± 14.8 years attending a hemodialysis kidney clinic at a tertiary referral hospital in Australia. On separate occasions, participants completed the SSQ, the SSQ-SF, and a feasibility questionnaire. Nursing staff from the same clinic completed a feasibility questionnaire.

Main Outcome Measures: Time and ease of completion; association and agreement between the SSQ and SSQ-SF scores; assessment of binary classifications for sodium consumption: sensitivity and specificity.

Results: Median time to complete the SSQ-SF was 4 minutes versus 10 minutes for the SSQ (P < .01); 93% of participants and nursing staff agreed that the SSQ-SF was easy to complete. There was strong and significant association between total SSQ and SSQ-SF scores (r = 0.777, P ≤ .01), with strong agreement between individual scores and no fixed bias. Compared with the SSQ, the SSQ-SF score cut-point of ≥50 successfully classified 23 of 27 participants as high sodium consumers: sensitivity 85% and specificity 68%.

Conclusion: The SSQ-SF is quick and feasible to implement in the clinical setting and may be a useful first step for screening the sodium intakes of kidney disease patients for referral into the nutrition care process.