Similarity index for sound-alikeness of drug names with pitch accents

Drug name similarity is one of major reasons of medical accidents. In order to prevent from the accidents, one of the best ways is to avoid approving drugs that has the names similar to that of existing drugs. It is well-known that there are two kinds of drug name similarity, look-alikeness and sound-alikeness. Nabeta et. al. proposed a look-alikeness similarity index,which excludes the sound-alikeness. Though, in Japan, oral prescription is basically prohibited, emergent situation can force a doctor to prescribe orally. In such a situation, medical accidents can occur. In this study, we proposed a sound-alikeness similarity index based on quantitative similarity of consonants. The consonant similarity was proposed based on The International Phonetic Alphabet (IPA). Overall drug name similarity is calculated based on Letter Sequence Kernel (LSK). The similarity calculation method takes account of the effect of plural pitch accents. We divided a drug name into some pieces at the position where a pitch accent changes, applied LSK to each of them, and combined them to obtain the value of the similarity index. The similarity index proposed in this study achieved relatively high correlation to the results of our experiment, r ≈ 0.8.