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HANCOCK Discussion
ET AL These results ma> be used to determine occupancy factors for
bed-planning methods. In comparison, other current planning methods,
such as that of Shonick [4], the Hill.-Burton formula, and the
Poisson sizing assumption, overestimate the number of beds needed in
most cases and are thus inappropriate. Shonick's methodology is the
same as the one in this study, but his model is different, and his results
cannot be put in the format used here. The lack of a call-in algorithm
as a census restorer will cause Shonick's method to have substantially
lower maximum average occupancies under identical cancellation and
turnaway constraints.
In Fig. 5c the results of the present study are compared with the
Hill-Burton formula, the Poisson assumptions, and the results obtained
by Hancock, Martin, and Storer [12], who used a similar but
less extensive approach. It is apparent that facilities can operate at
occupancies much higher than those predicted by Shonick, the Poisson
asssumptions, and the Hill-Burton formula. The exceptions occur
in cases where percent scheduled is high and the number of beds is
less than 75. In these cases the Hill-Burton formula predicts a somewhat
higher occupancy than is possible. Both the Hill-Burton and
Poisson modeis ignore important facility parameters that determine
maximum average occupancy.
Figure 5c shows that the occupancy curve derived by Hancock
falls in the same range as the results of this study, but its different
shape is attributable to the fact that Hancock used different turnaway
and cancellation constraints. His constraints were set at two cancellations
and two turnaways per month. Thus, in small facilities, two
per month represents a large percentage of arrivals, whereas in larger
faciliiies the percentage becomes smaller. This explains the "flatness"
of the curve derived by Hancock and also serves to point up the
sensitivity of the turnaway and cancellation constraints mentioned
earlier.
When sizing hospital facilities, all important parameters and characteristics
of these facilities must be evaluated. All parameters must
be consiaered collectively since their effects on occupancy are not independent.
The results of this study may be applied to the sizing of
individual facilities although it is important that factors not dealt
with in this paper also be taken into account. Specifically, if the turnaway
and cancellation constraints differ from those used here, one
must expect the occupancy to differ as well. Other factors such as
scheduling pattern, seasonal variations that cannot be smoothed by
admission scheduling, and (to a lesser extent) mean lengths of stay
should also be considered.
REFERENCES
1. Magerlein. D.B., W.M. Hancock, F.W. Butier, G.M. Mallett. and D.R. Young.
HEALTH New systems an mean real savings. Hosp Financ Manage 32:10 Apr 1978 and
SERVICES 32:18 May 1978.
RESER.CH 2. Magerlein. D.B.., R.J. Davis, and W.M. Hancock. The Prediction of Departmental
Activity and Itr Use in the Budgeting Proceus. Report No. 76-1. Bureau of
Hospital Administration. University of Michigan, Dec. 1976.