There was no relationship found between screening frequency and GPs interest in it (P = 1).
Next, we looked for associations between screening frequency and GPs' interest in PrG, between knowledge of PrG, respectively, knowledge of PrG network, and screening practice for PrG, and finally between the need for information/training on PrG and knowledge of the topic, using the Pearson chi-square tests.
Figure 4A provides a representation of the incremental cost-effectiveness of the strategies, showing the cost-effectiveness plane for costs versus life years and the relationship between screening technology, screening frequency and the relative increases in costs and effects.
We conducted subgroup analyses stratified by age, sex, socioeconomic status, screening method, screening frequency, and time interval since screening.
The main differences between these three countries and most other countries were the higher screening frequencies and broader age groups to whom screening was offered, by national programmes or by doctors.
Estimates of mortality reduction and overdiagnosis were highly dependent on screening frequency, age range, and uptake, which may explain differences between some previous estimates obtained from randomised trials and from service screening.
Gastric cancer patients were categorised by screening method (UGIS, endoscopy, and never screened), screening frequency (number of screenings received between 2002 and 2007: once, twice, three times or more, or never screened), and interval between date of gastric cancer diagnosis and the preceding screening date.
A logistic regression model was used to evaluate whether the year of first-ever screen, or grade at first-ever screen, affected the linear trend between screening year and frequency of STDR among participants attending for a second or subsequent screen (adjusting for age-group, sex, ethnicity, deprivation, and duration of diabetes and using one episode per participant per year).
Similarly, age at screening and screening frequency could not be included in regression models.
Two randomised trials compared a 1-year screening interval with a 3-year screening interval, one in women between age 40 and 49 years (Klemi et al, 1997) and one in women between age 50 and 62 years (Breast Screening Frequency Trial Group, 2002).
If the sensitivity of careHPV testing for detection of CIN2+ were reduced to 60%, the estimated reduction in cancer incidence and mortality would decrease to between 8-45% (depending on the screening frequency).
