Background: Cervical cancer has been a leading female cancer in Thailand for decades, and has been second
to breast cancer after 2007. The Ministry of Public Health (MoPH) has provided opportunistic screening with
Pap smears for more than 30 years. In 2002, the MoPH and the National Health Security Office provided
countrywide systematic screening of cervical cancer to all Thai women aged 35-60 years under universal health
care coverage insurance scheme at 5-year intervals. Objectives: This study characterized the cervical cancer
incidence trends in Songkhla in southern Thailand using joinpoint and age period cohort (APC) analysis to
observe the effect of cervical cancer screening activities in the past decades, and to project cervical cancer rates
in the province, to 2030. Materials and Methods: Invasive and in situ cervical cancer cases were extracted from
the Songkhla Cancer Registry from 1990 through 2010. Age standardized incidence rates were estimated. Trends
in incidences were evaluated by joinpoint and APC regression models. The Norpred package was modified for R
and was used to project the future trends to 2030 using the power of 5 function and cut trend method. Results:
Cervical cancer incidence in Songkhla peaked around 1998-2000 and then dropped by -4.7% per year. APC
analysis demonstrated that in situ tumors caused an increase in incidence in early ages, younger cohorts, and in
later years of diagnosis. Conclusions: Both joinpoint and APC analysis give the same conclusion in continuation
of a declining trend of cervical cancer to 2030 but with different rates and the predicted goal of ASR below 10
or even 5 per 100,000 women by 2030 would be achieved. Thus, maintenance and improvement of the screening
program should be continued. Other population based cancer registries in Thailand should analyze their data
to confirm the success of cervical cancer screening policy of Thailand.