Sir.—This letter is an addendum to the Marginal Comment I prepared on food additives and hyperkinesis for the November issue of the Journal (131:1204-1206, 1977). Some new findings make it necessary to modify slightly statements made there.
The study done by Goyette et al,1 demonstrated no differences, using global behavioral measures, between children who received food colorings and those who did not under double-blind conditions. However, slight decreases in performance (not achieving statistical significance) were noted on a test of sustained attention only when the test was administered in the first two hours after ingestion of food colorings. I commented that this finding needed replication.
Connors has completed a study designed to test this finding using behavioral measures rather than the test of sustained attention.1 Parents of 13 preschool, hyperkinetic children were asked to rate behavior, confining their observations to a three-hour period immediately following the ingestion