The existence of significant disparities between the prescribing costs
of dispensing and non-dispensing general practices has long been susp
ected, and received confirmation in a study of Lincolnshire, based on
data for 1990-91. This study subsequently attracted much criticism. In
this paper, we extend the analysis by considering annual cost and oth
er prescribing data for Lincolnshire for the years between and includi
ng 1990-91 and 1993-94, in the light of the prescribing criteria devel
oped by the Audit Commission. Our results show that dispensing practic
es had higher prescribing costs per patient for all the years analysed
. In 1993-94, dispensing practices prescribed more items per patient (
fewer of them generically) and were less capable of remaining within t
heir prescribing budgets. The essential difference in prescribing cost
s lies in the area defined by the Audit Commission as 'core prescribin
g'. Using the Audit Commission's criteria for 'rational' prescribing,
dispensing practices could make a significantly higher level of saving
s than non-dispensing practices. The findings lend support to the hypo
thesis advanced in the earlier analysis, namely, that the higher costs
of prescribing in dispensing practices are accounted for primarily by
management practice and the structure of incentives.