Effectiveness of quadrivalent human papillomavirus vaccine for the prevention of cervical abnormalities: Case-control study nested within a population based screening programme in Australia

Crowe, Elizabeth, Pandeya, Nirmala, Brotherton, Julia M. L., Dobson, Annette J., Kisely, Stephen, Lambert, Stephen B. and Whiteman, David C. (2014) Effectiveness of quadrivalent human papillomavirus vaccine for the prevention of cervical abnormalities: Case-control study nested within a population based screening programme in Australia. BMJ, 348 . doi:10.1136/bmj.g1458


Author Crowe, Elizabeth
Pandeya, Nirmala
Brotherton, Julia M. L.
Dobson, Annette J.
Kisely, Stephen
Lambert, Stephen B.
Whiteman, David C.
Title Effectiveness of quadrivalent human papillomavirus vaccine for the prevention of cervical abnormalities: Case-control study nested within a population based screening programme in Australia
Journal name BMJ
ISSN 1756-1833
0959-535X
Publication date 2014-03-04
Year available 2014
Sub-type Article (original research)
DOI 10.1136/bmj.g1458
Open Access Status DOI
Volume 348
Total pages 10
Place of publication London, United Kingdom
Publisher BMJ Publishing Group
Language eng
Formatted abstract
 Objective To measure the effectiveness of the quadrivalent human papillomavirus (HPV) vaccine against cervical abnormalities four years after implementation of a nationally funded vaccination programme in Queensland, Australia.

Design Case-control analysis of linked administrative health datasets.

Setting Queensland, Australia.

Participants Women eligible for free vaccination (aged 12-26 years in 2007) and attending for their first cervical smear test between April 2007 and March 2011. High grade cases were women with histologically confirmed high grade cervical abnormalities (n=1062) and “other cases” were women with any other abnormality at cytology or histology (n=10 887). Controls were women with normal cytology (n=96 404).

Main outcome measures Exposure odds ratio (ratio of odds of antecedent vaccination (one, two, or three vaccine doses compared with no doses) among cases compared with controls), vaccine effectiveness ((1−adjusted odds ratio)×100), and number needed to vaccinate to prevent one cervical abnormality at first screening round. We stratified by four age groups adjusted for follow-up time, year of birth, and measures of socioeconomic status and remoteness. The primary analysis concerned women whose first ever smear test defined their status as a case or a control.

Results The adjusted odds ratio for exposure to three doses of HPV vaccine compared with no vaccine was 0.54 (95% confidence interval 0.43 to 0.67) for high grade cases and 0.66 (0.62 to 0.70) for other cases compared with controls with normal cytology, equating to vaccine effectiveness of 46% and 34%, respectively. The adjusted numbers needed to vaccinate were 125 (95% confidence interval 97 to 174) and 22 (19 to 25), respectively. The adjusted exposure odds ratios for two vaccine doses were 0.79 (95% confidence interval 0.64 to 0.98) for high grade cases and 0.79 (0.74 to 0.85) for other cases, equating to vaccine effectiveness of 21%.

Conclusion The quadrivalent HPV vaccine conferred statistically significant protection against cervical abnormalities in young women who had not started screening before the implementation of the vaccination programme in Queensland, Australia.
Keyword Medicine, General & Internal
General & Internal Medicine
MEDICINE, GENERAL & INTERNAL
Q-Index Code C1
Q-Index Status Confirmed Code
Grant ID FT0990987
631691
50025
Institutional Status UQ

 
Versions
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 70 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 83 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Sun, 06 Apr 2014, 10:07:13 EST by System User on behalf of School of Public Health