Editing Spirometer (section)

====Motivations====
The use of reference values and discrete categorizations of sources of variability has been motivated by ideas of anthropometry and vital capacity. Studies have looked specifically at the relationship between anthropometric variables and lung function parameters.<ref name=":1">{{Cite journal|last1=Mohammed|first1=Jibril|last2=Maiwada|first2=Sa’adatu Abubakar|last3=Sumaila|first3=Farida Garba|year=2015|title=Relationship between anthropometric variables and lung function parameters among primary school children|journal=Annals of Nigerian Medicine|volume=9|issue=1|pages=20–25|doi=10.4103/0331-3131.163331|s2cid=75957978 |doi-access=free }}</ref>