Basic statistical tools.
By van Reeuwijk, L. P.
van Reeuwijk, L. P. (1998). Basic statistical tools. In Guidelines for quality management in soil and plant laboratories (FAO Soils Bulletin 74). Food and Agriculture Organization of the United Nations. https://www.fao.org/4/w7295e/w7295e08.htm
Chapter 6, "Basic Statistical Tools," of the FAO's Guidelines for Quality Management in Soil and Plant Laboratories provides an essential overview of statistical methodologies necessary for ensuring data accuracy, precision, and reliability in analytical testing. The chapter introduces fundamental concepts such as mean, standard deviation, variance, and confidence intervals, which are critical for routine laboratory quality control. It explains how to apply these basic statistical tools to evaluate measurement uncertainty, track procedural bias, and detect potential errors in daily lab operations. Additionally, the text covers the use of control charts to effectively monitor consistent laboratory performance and validate new analytical procedures. By employing these standardized techniques, technicians and scientists can rigorously conduct meaningful internal quality assessments and confidently interpret complex datasets. Ultimately, this chapter serves as a highly practical and foundational guide for personnel aiming to meet stringent international protocols for agricultural, environmental, and biological analytical data reliability and accuracy.