A Taste-intensity Visual Analog Scale: An Improved Zinc Taste-test Protocol

Studies employing methods for measurement of zinc sulfate taste acuity have had diverse results, and although the studies have had limitations in design and implementation, they have suggested salient findings beyond the assessment of taste acuity. These findings have included, but were not limited to, relationships between zinc sulfate taste acuity and weight, levels of serum zinc, diastolic hypertension, levels of salivary carbonic anhydrase 6, and frequency of illness. However, current protocols for zinc sulfate taste assessment are problematic and warrant improvement. The current study intended to compare the ranking scale for the original Bryce-Smith and Simpson zinc taste test (BS-ZTT) with a novel, taste-intensity visual analog scale (TI-VAS) to explore the potential for improved zinc sulfate taste-acuity measurement. Participants were administered a 0.1% solution of zinc sulfate and assessed using the 2 scales. The study took place at West Liberty University, in West Liberty, WV, USA. Participants were 500 West Liberty University students who volunteered to participate in the study. A strong, statistically significant, positive correlation existed between the BS-ZTT and the TI-VAS scores (r s = 0.79; P < .0001; n = 491). The study found that the BS-ZTT offered a limited number of ordinal variable ranks and depended on an examiner's evaluation. Conversely, the TI-VAS had an expanded range of variables and was independent of the examiner. The TI-VAS can be used as a taste-acuity test for zinc sulfate and as a benchmark for future analyses of zinc sulfate taste acuity and zinc taste tests.