Sensory assessment and acceptability of coated tablets relationship between instrumental methods and human data

Development of acceptable medicines is central for adherence and effectiveness of treatment. However, the assessment of medicines’ acceptability has not yet been standardised. Correlating in vitro and in vivo acceptability data would facilitate the development of acceptable medicines, but research in this area is limited. This thesis aims to evaluate and correlate in vivo and in vitro acceptability data of conventional tablets with a range of coatings. In two randomised studies participants, ranging from pre-school children to older adults, evaluated acceptability of tablets in two aspects: ease-of-swallowing and palatability. Sensory attributes which were statistically related to acceptability were established with high selectivity and specificity, i.e. bitterness, aftertaste, stickiness, slipperiness, and smoothness. Discrepancies found between children and adults responses indicated differences in their perception of tablets and acceptability. Also developed was an array of instrumental methods and results were investigated for links to sensory perception. A linear relationship between tribology and oral sensory perception, specifically for ease-of-swallowing, slipperiness and stickiness, of tablets was found and is described for the first time. Lastly, a vocabulary describing tablets has been collected and organized into a lexicon, which provides the first step towards the standardisation of sensory testing, as a part of acceptability evaluation.