BOOKS OF RtfiDIfGS - PAHO/WHO

.V'oL XVIII. No. 2. Stpphlidary diagnosis
(tLx), age, auid sex.
The number of groups formed by the
algorithm and the corresponding per cent
reduction i¡n unexplained variation tbr each
of the ,ai-'lttles are shown iii Tablle 3.
Sinc- the greatest reduction in unexplained
*ariation was achieved with operl,
and a linited mnhuher *of gr'oups (3) this
variaulle wvas considered thle prilne *- "ilidate
for initial subdivision of the caitegory.
The algorithli suggested 3 groups whose
vontetlns are described inl Tabl 'l e . This
table presetits the diillerent :;urgical procedures
contained in each groutp, the
corresponding number of observations
(SIZE), and the meait lengthi of stay
(MEAN). Note that Inorkt thal .98 per cent
of the obseraitions il tlihe tirst rtrollp have
no surgical procedure listed. The second
grotlp primarily contails ol>servationis with
relative!y mitior procedtres such as cystoscopy
a;i¡