
heterogeneity of the 'cleft palate population' and research designs
the primary point made in this paper is that we must reject the notion
that there is some inherent, universal commonality among individuals
who are born with a cleft lip and/or cleft palate.  we must recognize the
various pertinent subgroups within this population.  this does not mean,
however, that one must always recognize the smallest subgroup in doing a
given study.  on the contrary, we would defend the use of fewest possible
subgroups consistent with the specific research purpose.  nevertheless, we
feel that time spent considering the purposes of a study and the subgroups
which need to be identified will tend to minimize the number of
contradictory results, and will assist us in the interpretation of the
observations that our insight and technology make possible.
