Thanks for the link to the Landy study, I was looking for it. Assuming all the methodology and conclusions are correct, let's look at what if finds.
"To conclude, we have shown that screening has an even larger impact on cervical cancer mortality than it has on incidence, and that if everyone attended screening regularly, 83% of cervical cancer deaths could be prevented, compared with 70% with current screening."
Ok, that sounds really good, let's look at what it means in numbers.
"The estimates of the number of deaths from cervical cancer that could be prevented by regular screening or that are prevented by current screening rely on the assumption that the RRs calculated based on 5-year excess mortality approximate the RRs for cause-specific mortality. In this study, we group deaths by the age of cancer diagnosis not the age at death. Hence, screening (starting at age 25) will (most likely) increase the number of fatal cancers diagnosed at 25 years, even if it reduces (cumulative) cervical cancer mortality. Under the current screening programme, as the population age a large number of deaths that are not preventable by screening will occur after age 84 years, decreasing the relative benefit of screening overall."
So what they're saying there is that if a woman is diagnosed aged 25 with a cancer that eventually kills her aged 84, they're treating that as a fatal cancer in the 25-29 group.
What about the numbers?
"In England, there are an average of 796 deaths a year (2011–2014 average) from cervical cancer in women of all ages (Office for National Statistics, 2015). It is estimated that screening currently prevents 69.7% (95% CI: 66–73%) of cervical cancer deaths. However, if everyone attended screening regularly 82.9% (95% CI: 82–84%) of deaths could be prevented (i.e., half of deaths currently occurring could be prevented). Applying the RRs in Table 4 to the observed number of deaths in each age group, we estimate that there would be an additional 1827 deaths per year from cervical cancer in the absence of screening, and a further 347 deaths per year could be prevented if everyone attended screening regularly between ages 25 and 64 years."
These are all estimates, they're statistically sound estimates, but they're estimates, they have to be to carry out this kind of study. So we're talking screening 'saving' 2,200 lives per year.
But lets go back to what Dr McCartney reminded us of. You don't 'save' someone's life, you prolong it, unless you make them immortal.
So we're reducing mortality from cervical cancer, but in reality, how long will we actually prolong life by? Let's look back at those cervical cancer death statistics by age. Deaths increase with age, most women who die of cervical cancer are 85-59.
www.cancerresearchuk.org/health-professional/cancer-statistics/statistics-by-cancer-type/cervical-cancer/mortality#heading-One
So there you are aged 85. You haven't died of cervical cancer, hurrah! What's your life expectancy?
Oh no, it's 82.9 years, you died already.
www.huffingtonpost.co.uk/entry/life-expectancy-uk_uk_59ca2b4ee4b01cc57ff533f2
Actually assuming you live this long, you'll probably die of dementia, personally I don't find that an attractive prospect.