Final answer:
The PDCAAS and the newer DIAAS are both useful methods to evaluate protein quality in clinical practice, with DIAAS providing a more accurate assessment as it considers individual amino acid digestibility.
Step-by-step explanation:
The most useful method for evaluating protein quality in clinical practice is often considered to be the Protein Digestibility Corrected Amino Acid Score (PDCAAS). This method has been widely used and endorsed by international organizations such as the Food and Agriculture Organization and the World Health Organization. PDCAAS considers both the essential amino acid composition of a protein and its digestibility. However, the FAO recently recommended a shift towards the Digestible Indispensable Amino Acid Score (DIAAS), which takes individual amino acid digestibility into account, providing a more accurate assessment of protein quality. DIAAS is calculated using the formula: DIAAS % = 100 x [(mg of digestible dietary indispensable amino acid in 1 g of the dietary protein) / (mg of the same dietary indispensable amino acid in 1g of the reference protein)]. Compared to PDCAAS, the DIAAS is potentially more precise, as it does not truncate values at 100 and uses ileal digestibility, ideally human, for a more exact measure.