In　this　paper,　we　consider　the　between　estimator　under　the　intraclass　correlation　model　with　missing　data.　We　give　a　necessary　and　sufficient　condition　for　existing　exact　simultaneous　confidence　intervals　for　all　contrasts　in　the　means　under　the　between　transformed　model,　which　indicates　the　F-test　statistic　and　simultaneous　confidence　intervals,　constructed　by　Seo　et　al.　[T.　Seo,　J.　Kikuchi,　K.　Koizumi,　On　simultaneous　confidence　intervals　for　all　contracts　in　the　means　of　the　intraclass　correlation　model　with　missing　data,　J.　Multivariate　Anal.　97　(2006)　1976-1983]　based　on　the　between　estimator,　is　invalid.　Furthermore,　using　the　distribution　of　the　between　estimator,　we　present　the　exact　test　statistics　and　confidence　intervals　for　partial　contrasts.　Published　by　Elsevier　Inc.