“…Galant et al, 1977;Goldsworthy et al, 1981;Jonkman et al, 1981; Koysooko et al, 1974) have indicated a favourable correlation between the two, whilst others suggest that saliva is of little value (e.g. Boobis etal., 1979;Munch etal., 1981;Sharma et al, 1981). Some of the controversy might be explained by individual variability and our study was designed to investigate this in more detail.…”