Abstract
In 2006, the reimbursement system for the Civil Servant Medical Benefit Scheme(CSMBS) in Thailand
was changed to a direct billing system. It was unknown how this new system affected drug expenditures
and the number of drugs given to beneficiaries. The aim of this study was to assess the effects of the
direct billing system on prescribing patterns in terms of the number of months of coverage per prescription
and over possession. The study was undertaken using a retrospective cohort approach on the data
recorded in the database of a university hospital in the northern part of Thailand. We gathered data on all
patients with CSMBS coverage who came to the out-patients department between Oct 1, 2005 and Mar 31,
2007. Mean cost of medication, the number of months of coverage per prescription and the medication
possession ratio (MPR) of the five highest prices of oral medication were calculated for the one-year period
before and after the system was changed.
Results: Out of 43,897 patients seeking out-patient care at the hospital, 15,632 (36%) were covered
under CSMBS. Eighty-eight percent (13,785/15,632) received medications as a result of their visit. The
total cost of medication increased from 2 million baht to 4 million baht in one year. Glucosamine,
atorvastatin, rosiglitazone, clopidogrel and diacerein were the most frequently used in terms of cost. The
average number of months of coverage based on these medications increased from 1.29 to 1.48 months per
prescription. The percentage who were prescribed medication for more than 3 months, was slightly increased
from 1.82 to 2.43. Three out of five MPRs were higher after the system was changed (relative risk
ranged from 1.19 to 2.32).
Conclusion: The direct billing system may affect prescribing patterns, as indicated by the trend of
the increased number of months of coverage per prescription and the higher medication possession ratio
found in our study. Further evidence is still needed. Policymakers need to consider all relevant and
important consequences associated with the new system prior to decision-making for policy purposes.
