Title: Factors influencing cervical cancer re-screening in sub-Saharan Africa: a cohort study
Version: 1 Date: 03 Aug 2023
Reviewer's report:
The question covered in your article is of great importance for public health in Cameroon.
It touches on issues of gender equity and economic status. It is also part of a global effort
to eliminate cervical cancer, in conjunction with the HPV vaccination strategy and early
management of pre-cancerous lesions.
The work should be published to inform strategic decision-making to eliminate cervical cancer
as a public health problem by 2030 in Cameroon.
However, I'm concerned about a few details that need to be reviewed to give a certain value
to the results.
(i) On the title, must be as precise as possible. When I read the title, I thought it was a systematic
review of several articles dealing with the same subject in sub-Saharan African countries. Your
study cannot claim to describe the situation in Cameroon, far less in sub-Saharan Africa. I
suggest that you limit yourself to characterizing your study environment, for example .... in a
semi-rural, rural or urban health district, depending on the case of the Dschang Health District.
(i) In the introduction, the strategy for eliminating cervical cancer should be clearly set out to
explain the critical role of regular screening. An appraisal of what is happening in Cameroon
would also be useful to show the gap and the extent of the effort required to achieve elimination.
As far as I know, screening is recommended every 2 to 3 years for all women over a certain
age. It is possible to have several sources of recommendations, but it would be appropriate to
include Cameroon's recommendations, if there are any, or to use the WHO's recommendations
on cervical cancer screening.
(iii) The type of study you refer to for the question seems inappropriate to me. In fact, you are
collecting data only once, by phone, from the people you have identified as being part of your
study population. It is more likely to be a cross-sectional study.  The sampling base used to
select the study population is unclear. Is it from the hospital's screening unit register, or is it a
sub-population from a previous study? If it is in the hospital registry, the ideal is to check in
the registry whether women screened in 2015 have come back as recommended, instead of just
collecting data over the phone. This is a huge source of bias.  Also, taking all screen-positive
women first and completing it with screen-negative women to form your study population is
a huge bias as you use this factor for comparison. The question is to know what proportion of
women undergo regular screening within the recommended time interval, and what the factors
of adherence are. We can also apply the reciprocal, i.e. look for the proportion of women who
do not comply with the screening interval and find out the factors involved. In both cases, the
selection of the study population has to be random for all the people in the sampling base if
the "screening results" factor is to be used to look for an association with adherence to regular
screening or not. It is also difficult to say that a case-control study is being carried out using
screening results to identify cases and controls.
Overall, English should be improved by having it reviewed by a language professional to
improve style, reduce text length and remove superfluous material.