United Kingdom - Scotland Survey of Urinary Sodium and Potassium Excretion 2006

This study consisted of both a 24-hour measurement and three spot samples from each respondent, with the aim of establishing the extent to which findings from the spot samples correlate with those from the 24-hour samples. Participants were selected using sampling from the Scottish Health Survey 2003, and a random digit dialing sample. In the case of the latter, the telephone interviewers asked a household questionnaire that covered basic demographic details and some information on eating habits. Nurses then visited co-operating households.

Overall, 574 adults (243 men, 331 women), aged 19 - 64, completed the study and provided spot urine samples and one 24-hour sample (448 from the SHS sample, and 126 from the random digit dialling sample). This included 7 who provided a 24-hour sample and two out of three spot samples. In analysis, 10 samples were discarded because of incomplete or inconsistent labelling, leaving 564 useable samples.