Relative condition factor: Le Cren's legacy for fisheries science

Abstract: Aim In this paper we present a scientometric analysis aimed at to assess and quantify the contribution of Le Cren’s condition factor and the main ideas advanced by ‘Le Cren, 1951’ to studies on the health of individuals or populations in aquatic environments. Specifically, we addressed the following questions: (i) what are the temporal and spatial citation trends of ‘Le Cren, 1951’?; (ii) Which journals cited ‘Le Cren, 1951’ most frequently?; (iii) In which types of aquatic environments and organisms have Le Cren’s condition factor been most commonly applied?; (iv) Which of the main applications addressed in ‘Le Cren, 1951’ have been most frequently used by fisheries scientists?; (v) Which of the methods (i.e., Quételet’s index or body mass index, Fulton’s condition factor, Le Cren’s condition factor, relative weight, residual index and scaled mass index) used to estimate condition factor identified in the papers that cited ‘Le Cren, 1951’ have been most frequently used? In addition, the main criticisms of the use of the relative condition factor are discussed. Methods We carried out a scientometric analysis on the papers published from 1951 to December 2015 that cited Le Cren’s article. The papers were obtained from the Thomson Reuters database (ISI Web of Knowledge, apps.isiknowledge.com) in May 2016. Results In total, 1128 papers were assessed. The number of citations increased significantly over time. Most citations occurred in two journals (Journal of Fish Biology and Journal of Applied Ichthyology). Most of papers were carried out in marine environments. In addition, we show that Le Cren's paper has been cited mainly in articles that estimate the condition factor or the weight-length relationship of populations. Finally, we emphasize that the relative condition factor proposed by Le Cren in 1951 is still the main method used to estimate the body condition of an individual or population. Conclusions Le Cren's significant contribution to animal well-being is undeniable, and we emphasize that among the methods identified in the papers that cited ‘Le Cren, 1951’ that estimated body condition, the relative condition factor proposed by Le Cren in 1951 is still the most commonly used method.摘要：研究目的 本文开展科学计量分析，旨在评估并量化勒克伦条件系数（Le Cren’s condition factor）以及“勒克伦，1951年”提出的核心学术观点，对水生环境中个体或种群健康研究的贡献。具体而言，我们针对以下问题展开研究：(i) “勒克伦，1951年”的时空引用趋势如何？(ii) 哪些期刊对“勒克伦，1951年”的引用频次最高？(iii) 勒克伦条件系数最常应用于哪些类型的水生环境与生物类群？(iv) 渔业科学家最常使用“勒克伦，1951年”中阐述的哪些主要应用场景？(v) 在引用“勒克伦，1951年”的文献中，用于估算条件系数的各类方法（即凯特勒指数（Quételet’s index）或身体质量指数（body mass index）、富尔顿条件系数（Fulton’s condition factor）、勒克伦条件系数、相对体重（relative weight）、残差指数（residual index）以及标准化体重指数（scaled mass index））中，哪一种的使用频次最高？此外，本文还讨论了使用相对条件系数的主要争议点。 研究方法 我们对1951年至2015年12月期间发表的引用勒克伦论文的文献开展科学计量分析。相关文献于2016年5月从Thomson Reuters数据库（ISI Web of Knowledge，apps.isiknowledge.com）获取。 研究结果 本次共评估1128篇文献。引用频次随时间呈显著上升趋势。绝大多数引用集中在两种期刊：《鱼类生物学杂志》（Journal of Fish Biology）与《应用鱼类学杂志》（Journal of Applied Ichthyology）。多数研究在海洋环境中开展。此外，本文发现勒克伦的论文主要被用于估算种群条件系数或体重-体长关系的文献中。最后，我们指出，勒克伦1951年提出的相对条件系数仍是估算个体或种群身体状态的主流方法。 研究结论 勒克伦对动物健康研究的重要贡献毋庸置疑，我们进一步强调，在引用“勒克伦，1951年”且涉及身体状态估算的文献所采用的各类方法中，勒克伦1951年提出的相对条件系数仍是使用最为广泛的方法。