“…Similarly, too much reliance cannot be placed on infrequent post-operative inquiries about a child's health (Hadfield, 1950;Johnston and Watkins, 1954). It has been shown by Dingle, Badger, Feller, Hodges, Jordan, and Rammelkamp (1953) and Brimblecombe, Cruickshank, Masters, Reid, Stewart, and Sanderson (1958) that, with a system of frequent home visiting, reasonably accurate records can be obtained. A study of the effects of tonsillectomy employing this method of collecting data eliminates a serious source of error.…”