Data and study population
This study used raw data from the 2017 Korea Community Health Survey (KCHS) conducted by the Korea Centers for Disease Control and Prevention (KCDC). The KCHS is a general statistic approved by Statistics Korea (Approval number 117075) conducted per Article 4 (Community health survey) of the Regional Public Health Act and Article 2 (Method and content of the community health survey) of the Enforcement Decree of the same Act . After selecting a sample plot through probability proportional to size sampling in tong, ban, and ri units, households for the survey were selected through systematic sampling. Trained examiners visited each of the selected households and conducted a face-to-face interview survey using computer-assisted personal interviewing (CAPI) . Data from the KCHS are open-data and can be used as primary data through The KCHS website after submitting a data usage plan. Of the total 228,381 respondents, 2,414 family caregivers of individuals with dementia who answered “yes” to the following question such as “Does your household currently include a patient diagnosed with dementia by a physician?” were selected as participants of this study.
The dependent variables of this study were health checkups and cancer screening participation. Health checkups participation was assessed using the question “Have you had health checkups (excluding cancer screening) in the past two years just to check your health status even though you don’t have any particular health problems?” The health checkups include the national general health checkups which are conducted every other year. Those who answered “no” to the question were classified as people who had not received health checkups, and those who answered “yes” were classified as people who had received health checkups.
Cancer screening participation was also assessed using the following question: “Have you had a cancer screening in the past two years just to check your health status even though you don’t have any particular health problems?” The cancer screenings include the national cancer screening for stomach cancer, liver cancer, colon cancer, breast cancer, cervical cancer, and lung cancer. Those who answered “no” to the question were classified as people who had not received cancer screening, and those who answered “yes” were classified as people who had received cancer screening.
The following demographic factors were assessed: gender, age, and marital status. Age was divided into 19-44 years, 45-64 years, and ≥ 65 years. Marital status was classified into single, married, and other (divorced, widowed, separated) using the marital status item. Area of residence was classified into capital (Seoul Special City, Incheon Metropolitan City, and Gyeonggi Province) and non-capital (all other cities and provinces).
As socioeconomic factors, education level, occupation category, and income level were assessed. Education level was classified into below elementary school graduates, middle school graduates, high school graduates, and college graduates or higher using the highest education and graduation items. Occupation category was classified into white collar (managers, professionals and relevant workers, office workers), sales and service (service workers, sales associates), blue collar (agricultural, forestry, and fishery workers, technicians and relevant technical workers, device, machine manipulation and assembly workers, and elementary workers), and others (students, housewives, unemployed). Income level was classified into < 2 million KRW, 2–4 million KRW, and > 4 million KRW.
As health status factors, subjective health status, stress levels, symptoms of depression, and chronic disease were assessed. Subjective health status and stress levels comprise a table which is self-reported by subjects. Subjective health status was classified into good (very good and good), moderate (moderate), and poor (poor and very poor). Subjective stress levels were assessed based on daily levels of stress and classified into very high, high, low, and very low. Depression was classified as “no” for mild depression below 9 points and “yes” for severe depression above 9 points using the PHQ-9. Chronic disease was classified into “yes” for those who had one or more of the chronic diseases investigated in the KCHS (hypertension, diabetes mellitus, dyslipidemia, stroke, myocardial infarction, arthritis, cataract).
The general characteristics and distributions for each factor were analyzed using frequency analysis, and the data were presented as frequencies and percentages. The associations of each factor with health checkups and cancer screening participation were analyzed with likelihood ratio tests. Factors associated with health checkups and cancer screening participation were identified using binomial logistic regression analysis. Data were statistically processed using the SPSS 22.0 software.