Background: The traditional Chinese medical literature provides a substantial resource for natural products research. When undertaking systematic searches, investigators need to assess the scope, content, and relevance of collections both singly and in comparison.
Objectives: This study examines eight collections of pre-modern literature, develops an approach to quantitatively assess their content, and compares their relative inclusivity.
Methods: All publications listed in each collection were collated and a uniform scoring system was developed to account for variant editions, incorporation of multiple books under a single title, addition of commentaries, and other factors affecting content. Comparisons were undertaken between collections to determine the degree of overlap, genres of literature represented, and relevance to natural products research.
Results: Following adjustments for differences in how books were listed, duplications, and variant editions, Zhong Hua Yi Dian (Encyclopaedia of Traditional Chinese Medicine) (4th edition CD) is the largest collection of complete books containing 1009 different books. Zhong Guo Ben Cao Quan Shu (The Complete Collection of Traditional Texts on Chinese Materia Medica) contains 2026 titles including multiple editions and extracts, so after adjustments the number of different complete books is approximately 740. No collection was fully inclusive of the others, but Zhong Hua Yi Dian includes between 52.1% and 91.5% of the books in the six smaller collections.
Conclusions: Comparing traditional collections is complex due to variant editions and multiple titles. This necessitates examination of the text rather than title alone. Prior to undertaking systematic searches, the characteristics of collections need to be investigated, duplicated books identified, and differences between editions should be assessed. Its size, electronic format, and broad spread of genres makes Zhong Hua Yi Dian suitable for systematic searches, but due to the lack of bibliographical detail on included books, cross-referencing to other collections is recommended.