Governance of Preventive Health Intervention and on Time Verification of its Efficiency in a Region of Southern Italy : The Giove Study

Background: Human Papillomavirus (HPV) vaccination programmes should substantially reduce costs generated by HPV-related diseases. More valuable economic results were showed with predictive models based on a multi-cohort vaccination strategy. In a region of southern Italy, a quadrivalent-based anti-HPV vaccination programme involving 4 cohorts of girls was recently started. The aim of the GIOVE study was to evaluate the allocative efficiency of resources used in a vaccination programme implemented for the prevention of HPV-induced diseases in the Basilicata Region. Methods: An observational and retrospective study was designed. All girls living in Basilicata, aged 12, 15, 18, and 25, with a recorded vaccination were considered eligible for enrolment. The study period started in July 2007 and continued for 18 months to ensure a full compliance with the recommended vaccination schedule (0, 2, 6 months) in a 12-month time horizon. A bound optimization model was developed and adapted to measure the allocative efficiency of resources used by the Region for a vaccination programme which was based on a predetermined level of budget. The vaccination coverage rate was considered as an efficiency indicator of the best benefit achievable with a given budget constraint. A sensitivity analysis was performed to asses the uncertainty associated with the allocative efficiency estimates (vaccine costs and budgets allocated). Results: With a cost of vaccine equal to € 100 per dose, a vaccination coverage rate of 59.6% should be achieved to accomplish an effective resource allocation. Overall, a vaccination coverage rate corresponding to 72.8 ± 2.0% was observed in the Basilicata Region. The allocative efficiency indicator was 21.3% higher compared with the Regional public health objective (predetermined at 60.0%), and the resulting difference was statistically significant (p<0.001). The highest coverage vaccination rate was reported in the cohort of girls aged 12 (84.7% ± 2.0%). On the contrary, a statistically significant lower coverage rate (52.1% ± 3.1%) was recorded in the cohort of women 25 years old. When the price of the vaccine declined to € 85 per dose, the optimal vaccination coverage rate raised to 69.5%. Conclusions: The Basilicata Region attained in 12 months an outstanding result as documented by the achievement of an allocative efficiency indicator significantly high. The bound optimization model was found a very useful and rational approach for a short-term assessment of the efficient use of resources allocated for the implementation of a multi-cohort quadrivalent-based HPV vaccination programme. Further probabilistic models or observational studies designed to minimize the uncertainty associated with the excess of variables that must be considered in HPV vaccination programmes and based on real outcome measurements are strongly suggested