Santos JA et al estimated mean population salt intake in Fiji and Samoa using spot urine samples compared with measured salt intake from 24 hour urine samples in a sample of 414 and 725 participants from Fiji and Samoa respectively.
They found that the INTERSALT equation with potassium produced the closest salt intake estimates in both samples, and identified the presence of proportional bias for most spot urine equations.
The authors suggest additional studies are needed to assess whether spot urine samples can be used to estimate mean population salt intake in these populations.