By happenstance, the week after the BMJ �Short cuts� (1) summarized the paper by Sankaranarayanan et al that HPV testing can reduce cervical- cancer mortality (RR 0.52) (2) the Lancet published its editorial on harms from screening (3). However none of the many reviews of the study on �HPV- testing� questioned the wisdom of author�s suggestion that screening for HPV would be an efficient way to reduce cervical cancer. We hope our letter will redress that situation.
The problem of quoting relative risk without giving the absolute risk has been highlighted repeatedly in the BMJ (4,5). The cervical-cancer death-rate in the control group of the study can be used to calculate the risk in the population without any screening program. There were 64 deaths in 8 years in the population of 31,488 making for an absolute risk of 2.5/10,000/year. The absolute risk reduction in this case works out to be 0. 00013.
The cost of the HPV testing strategy is much higher than �$20 for each woman over 30�, suggested by the authors. 10% women showed up positive on HPV testing and they needed further investigations including repeated PAP smear examinations and biopsies to effect this lowering of mortality. The costs for all these procedures needs to be added up and weighed against the ARR of 0.00013. The intangible costs of the anxiety to 10% of the population of women, who need these repeated examinations, also need consideration.
1. BMJ Short Cuts HPV test is best for a single round of cervical cancer screening in India. BMJ 2009;338:b1423
2. Sankaranarayanan R, Nene BM, Shastri SS, Jayant K, Muwonge R, Budukh AM, Hingmire S, Malvi SG, Thorat R, Kothari A, Chinoy R, Kelkar R, Kane S, Desai S, Keskar VR, Rajeshwarkar R, Panse N, Dinshaw KA. HPV screening for cervical cancer in rural India. N Engl J Med. 2009;360:1385- 94.
3. Editorial. The trouble with screening Lancet 2009;373:1223
4. Campbell MJ. Resting heart rate as predictor. What about absolute risks? BMJ. 2009;338:b1197
5. Alonso-Coello P, Garc�a-Franco AL, Guyatt G, Moynihan R. Drugs for pre-osteoporosis: prevention or disease mongering? BMJ. 2008;336:126-9.