Dietary compliance
Energy and macronutrient intake were similar at baseline.
Compliance with the protein prescription was monitored
by a daily food checklist and a food frequency questionnaire
(at baseline, 4 and 12 months) and was also assessed
by 24 h urine urea excretion. At baseline urea excretion did
not differ significantly between groups (496 31 and
521 32 mmol/24 h in HPD and SPD respectively;
p Z 0.41). At 12 months the UUE was not significantly
different compared to baseline (p Z 0.13), however the
adjusted urea excretion at 12 months was significantly
different between groups (519 39, for the HPD and
456 25 for the SPD group; p Z 0.04) indicating
compliance to the protein prescription. This was confirmed
by self-reported diet data (supplement Appendix 5).