Introduction
Methods
Data and study population
Measures
Dependent variables – health-related outcomes
Variables name | Variable description / operationalisation | Data source and timeframe |
---|---|---|
Dependent variables – Health related outcomes | ||
Preventive dental care among adult population aged 18 years and over | The selected indicator is the proportion of the adult population aged 18 years and over who had at least one contact with a dentist in the reference period, i.e. in 2018, for preventive care such as an oral examination, a prophylactic cleaning, scaling, etc. The specific NIHDI nomenclature codes for the preventive dental care can be found in [32]. | BCHI, 2018 |
Purchase of antibiotic among population aged 18 years and over | This indicator is defined as the proportion of the population aged 18 years and over with at least one purchase of antibiotics between 01/07/2018 and 30/06/2019. Pharmanet data were used to identify cases of purchase of antibiotics. Purchase of a prescribed antibiotic was defined as having obtained at least one reimbursement of prescribed medicine belonging to ATC-code group J01 (antibacterials for systemic use) purchased from a public pharmacy (see Table A1 in the supplementary file). As antibiotic purchase has probably a seasonal pattern, there may be more than one peak in antibiotics use in a calendar year. Therefore in order to include only one winter peak per 12-month period, instead of the months January to December, we used the period from July 01, 2018 to June 30, 2019 to express the annual antibiotic purchase [33]. | BCHI, 2018–2019 |
Vaccination against flu among community dwelling older people aged 65 years and older | The indicator expresses the proportion of the population aged 65 years and over that is vaccinated against flu in the reference period, i.e., calendar year 2018. Older people aged 65 years and over residing in an institution (rest homes and the rest and care homes) were excluded because in the BCHI data only vaccines which have been reimbursed are taken into account and since 2010 vaccines are free of charge for older people residing in an institution in Flanders [34]. Hence the calculations for this indicator may result in an underestimation of the true coverage rate. All vaccines belonging to the ATC 4 class J07BB (anti-influenza vaccines) were considered. | BCHI, 2018 |
Mental health | The purchase of antidepressants is used as a proxy of mental health. The indicator expresses the percentage of adults aged 18 years and over with at least one purchase of an antidepressant [34] (ATC code = N06A) in 2018. | BCHI, 2018 |
Breast cancer screening among women aged 50–69 year in 2018 | Proportion of women aged 50–69 having received at least one mammogram within the last two years, i.e., within the reference year or the reference year-1. In the BCHI data source, the mammographies realized within the screening programme follow a specific procedure, and have their own billing codes. However, these codes do not allow to sufficiently discriminate screening within the program from the other mammographies (opportunistic screening, diagnostic evaluation). Therefore, in this study, all mammograms are considered, within or outside the context of the organised screening programme and we assumed that the largest part of the mammographies undergone between 50 and 69 is made for screening purposes, and therefore we used this information as a proxy of the breast cancer screening. The NIHDI nomenclature codes used can be found in Table A1 in the supplementary file. | BCHI, 2017–2018 |
Perceived health status among population aged 18 years and over | Perceived health status is based on the single question: “How is your health in general?”. This question is part of the Minimum European Health Module (MEHM), which is internationally used. Five response categories are possible: Very good / Good / Fair / Poor / Very poor. The response categories Very good / Good are recorded as “Good” and those Fair / Poor / Very poor as “Poor”. | BHIS, 2018 |
Physical activity among population aged 18 years and over | This refers to non-work-related physical activity (leisure-time physical activity and/or the use of a bicycle for commuting) meeting WHO recommendations: spend at least 150 min per week in physical activities of at least moderate intensity. The Physical Activity Questionnaire developed by European Health Interview Survey (EHIS-PAQ) was used to assess physical activity. This is a dichotomous variable (Practice of physical activity / No practice of physical activity). | BHIS, 2018 |
Type of diet among population aged 18 years and over | The type of diet was assessed using a short food frequency questionnaire. The indicator refers to the proportion of the population aged 18 years and over who eat the recommended daily amount of fruit and vegetables, i.e., at least 5 portions fruits and vegetables (Healthy diet) or not (Unhealthy diet). | BHIS, 2018 |
Consumption of alcohol among population aged 18 years and over | The EHIS wave 3 questions [35] are used to measure alcohol consumption in order to comply to the European Regulation which recommends the use of a harmonized approach in all EU Member States. The indicator expresses the drinking frequency in the past 12 months preceding the survey: Daily / Weekly / Monthly / Less than monthly / None. These categories are dichotomized as: at least once a week/less than once a week) among the population aged 18 years. | BHIS, 2018 |
Consumption of tobacco among population aged 18 years and over | Proportion of the population aged 18 and over who currently smoke (daily or occasionally). The tobacco consumption is a dichotomous variable (Yes / No). | BHIS, 2018 |
Independent variables | ||
Educational attainment | Educational attainment is based on the highest level of education achieved in the household. Possible values are “primary or no degree”, “secondary inferior”, “secondary superior”, and “superior education” following the ISCED-11 classification, whereby superior education includes all obtained degrees higher than secondary superior [36]. These values are recorded into two categories for the analyses: higher secondary education or lower (“primary or no degree”, “secondary inferior”, “secondary superior”) and higher education (“superior education”). | BHIS, 2018 |
Household income level | The quintiles of the equivalent household income (quintile 1: <750, quintile 2: 751–1000, quintile 3: 1001–1500, quintile 4: 1501–2500, quintile 5: >2500) were recoded in low (quintile 1–3) and high (quintile 4 and 5). | BHIS, 2018 |
Mediator variable | ||
Health literacy (HL) among population aged 18 years and over | The HL level was assessed in the BHIS 2018, using the 6-items European Health Literacy Survey Questionnaire (HLS-EU-Q6), which is a short- form of the original 47-items tool (HLS-EU-Q47) [31]. Like the original, the HLS-EU-Q6 is a self-reported tool whereby participants are asked how easy or difficult they find it to perform an information-related task, using Likert-type responses (“very easy” = 4; “fairly easy” = 3; “fairly difficult” = 2; “very difficult” = 1. “Don’t know” or refusal were recoded as missing. The six items covered are: • Judge when you may need to get a second opinion from another doctor • Use information the doctor gives you to make decisions about an illness • Find information on how to manage certain mental health problems like stress or depression • Judge if the information on health risks in the media is reliable? (Examples: TV, Internet or other media) • Find out about activities that are good for your mental well-being? (Examples: meditation, sport, walking,…) • Understand information in the media on how to get healthier? (Examples: Internet, newspapers, magazines). The scale final score measuring HL is the mean value on the six items, which varies between 1 and 4. Only respondents who answered at least 5 items were considered. Based on the final score, three possible levels of HL are defined: insufficient level of HL (1 ≤ x ≤ 2); limited level of HL (2 < x < 3); sufficient level of HL (3 ≤ x ≤ 4). In this study, HL was a dichotomous variable grouping together insufficient and limited levels of HL as “low HL” - vs. ”sufficient level of HL”. | BHIS, 2018 |
Confounding variables | ||
Age | Respondents age (in years) | BHIS, 2018 |
Sex | Respondents gender (Male / Female) | BHIS, 2018 |
Independent variables – socioeconomic status
Mediator variable
Statistical analysis
Descriptive analysis
Mediation analysis
Results
Descriptive statistics
Participants characteristics
Total | Sufficient level of HL | Insufficient level of HL | P value | |||||||
---|---|---|---|---|---|---|---|---|---|---|
N | Unweighted % (sample) | Weighted % (population) | n | Unweighted % (sample) | Weighted % (population) | n | Unweighted % (sample) | Weighted % (population) | ||
All | 8080 | 100 | 100 | 5255 | 66.0 | 65.8 | 2825 | 35.0 | 34.2 | |
Sex | 0.0141 | |||||||||
Male | 3812 | 47.2 | 48.0 | 2517 | 66.0 | 67.2 | 1295 | 34.0 | 32.8 | |
Female | 4268 | 52.8 | 52.0 | 2738 | 64.1 | 64.5 | 1530 | 35.9 | 35.5 | |
Age, mean ± SE | 8080 | 51.8 ± 18.0 | 50.5 ± 0.3 | 5255 | 51.8 ± 17.5 | 50.5 ± 0.4 | 2825 | 52.0 ± 19.0 | 50.5 ± 0.6 | 0.9414 |
Educational attainment | ||||||||||
Higher secondary education or lower | 4243 | 52.5 | 53.2 | 2527 | 59.6 | 60.3 | 1716 | 40.0 | 39.7 | < 0.0001 |
Higher education | 3837 | 47.5 | 46.8 | 2728 | 71.1 | 72.1 | 1109 | 28.9 | 27.9 | |
Income | < 0.0001 | |||||||||
Lower income | 4149 | 51.3 | 47.8 | 2532 | 61.0 | 61.1 | 1617 | 39.0 | 38.9 | |
Higher income | 3931 | 48.7 | 52.2 | 2723 | 69.3 | 70.1 | 1208 | 30.7 | 29.9 |
Prevalence of health outcomes
Association between health literacy, educational attainment, household income and health related outcomes
Association between HL and SES
Odds Ratioa (95% CI) | |||
---|---|---|---|
Subgroup aged 18 years and overb | Women aged 50–69 yearsc | Subgroup aged 65 years and overd | |
Educational attainment | |||
Higher secondary education or lower | 1.69 (1.53–1.86)*** | 2.09 (1.63–2.67)*** | 1.98 (1.57–2.50)*** |
Higher education | 1 | 1 | 1 |
Income category | |||
Lower income | 1.45 (1.30–1.64)*** | 1.55 (1.17–2.04)** | 1.71 (1.33-2.00)*** |
Higher income | 1 | 1 | 1 |
Association between SES and health related outcomes
Association between SES and health behaviour
Odds Ratioa (95% CI) | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Health behaviour | Health status | Use of medicine | Preventive health care | |||||||
Physical activity | Healthy diet | Alcohol consumption (At least once a week) | Tobacco consumption (Current smokers) | Good perceived health | Poor mental health | Purchase of antibiotics | Preventive dental care | Vaccination against flu | Breast cancer screening | |
Health literacy | ||||||||||
Insufficient level of HL | 0.79 (0.68–0.93)** | 0.72 (0.58–0.89)** | 0.86 (0.74–0.99)** | 1.25 (1.03–1.53)** | 0.56 (0.46–0.68)*** | 1.51 (1.21–1.88)** | 1.03 (0.88–1.20) | 0.99 (0.85–1.15) | 1.25 (0.86–1.81) | 0.89 (0.60–1.33) |
Sufficient level of HL | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Educational attainment | ||||||||||
Higher secondary education or lower | 0.54 (0.48–0.62)*** | 0.49 (0.41–0.58)*** | 0.40 (0.36–0.45)*** | 1.85 (1.59–2.15)*** | 0.51 (0.44–0.59)*** | 1.37 (1.15–1.63)** | 1.20 (1.01–1.29)** | 0.48 (0.43–0.55)*** | 1.07 (0.84–1.35) | 0.64 (0.49–0.84)** |
Higher education | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Educational attainment and HL interaction term | 0.89 (0.70–1.13) | 0.93 (0.67–1.29) | 1.00 (0.82–1.23) | 0.96 (0.75–1.23) | 0.89 (0.70–1.13) | 0.98 (0.73–1.31) | 1.09 (0.87–1.36) | 0.70 (0.51–0.95)** | 0.89 (0.57–1.40) | 1.00 (0.60–1.66) |
Odds Ratioa (95% CI) | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Health behaviour | Health status | Use of medicine | Preventive health care | |||||||
Physical activity | Healthy diet | Alcohol consumption (At least once a week) | Tobacco consumption (Current smokers) | Good perceived health | Poor mental health | Purchase of antibiotics | Preventive dental care | Vaccination against flu | Breast cancer screening | |
Health literacy | ||||||||||
Insufficient level of HL | 0.76 (0.65–0.89)** | 0.68 (0.55–0.85)** | 0.80 (0.69–0.93)** | 1.22 (1.02–1.47)** | 0.53 (0.43–0.65)*** | 1.45 (1.14–1.85)** | 1.08 (0.91–1.28) | 0.96 (0.83–1.12) | 1.60 (1.04–2.45)** | 0.90 (0.60–1.35) |
Sufficient level of HL | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Income category | ||||||||||
Lower income | 0.69 (0.60–0.78)*** | 0.78 (0.67–0.92)** | 0.50 (0.44–0.57)*** | 1.64 (1.39–1.92)*** | 0.50 (0.42–0.58)*** | 1.45 (1.19–1.78)** | 1.06 (0.93–1.20) | 0.59 (0.52–0.68)*** | 1.02 (0.78–1.34) | 0.54 (0.41–0.71)*** |
Higher income | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Income and HL interaction term | 0.89 (0.71–1.13) | 0.90 (0.65–1.25) | 1.03 (0.84–1.27) | 1.05 (0.81–1.35) | 0.93 (0.72–1.20) | 1.06 (0.77–1.45) | 1.03 (0.83–1.28) | 0.85 (0.69–0.99)** | 0.66 (0.39–1.11) | 0.97 (0.58–1.59) |
Association between SES and health status
Association between SES and use of medicine
Association between SES and use of preventive care
Association between HL and health related outcomes
Mediation effect of health literacy
Mediation effect of HL on the relationship between educational attainment and health related outcomes
Odds Ratiob (95% CI) | |
---|---|
Health behaviour | |
Practice of physical activity vs. No practice of physical activity | |
Total Effect | 0.51 (0.45–0.56)*** |
Direct effect | 0.53 (0.47–0.59)*** |
Indirect effect | 0.96 (0.94–0.98)** |
Percentage mediated (%) | 4.1 (1.7 to 6.5)** |
Healthy diet vs. Unhealthy diet | |
Total Effect | 0.46 (0.40–0.52)*** |
Direct effect | 0.48 (0.41–0.56)*** |
Indirect effect | 0.96 (0.93–0.98)** |
Percentage mediated (%) | 3.8 (1.2 to 6.5)** |
Alcohol consumption (At least once a week vs. Less than once a week) | |
Total Effect | 0.39 (0.36–0.43)*** |
Direct effect | 0.40 (0.36–0.44)*** |
Indirect effect | 0.98 (0.96–0.99)** |
Percentage mediated (%) | 1.1 (0.1 to 2.2) |
Tobacco consumption (current smokers vs. No current smokers) | |
Total Effect | 1.87 (1.64–2.09)*** |
Direct effect | 1.83 (1.60–2.05)*** |
Indirect effect | 1.02 (1.01–1.04)** |
Percentage mediated (%) | 4.8 (0.4 to 9.3) |
Health status | |
Good perceived health vs. Poor perceived health | |
Total Effect | 0.46 (0.41–0.52)*** |
Direct effect | 0.50 (0.43–0.56)*** |
Indirect effect | 0.93 (0.91–0.95)*** |
Percentage mediated (%) | 6.4 (3.9 to 9.0)*** |
Poor mental health status | |
Total Effect | 1.43 (1.24–1.61)*** |
Direct effect | 1.36 (1.18–1.54)** |
Indirect effect | 1.05 (1.02–1.08)** |
Percentage mediated (%) | 16.0 (5.2 to 26.7)** |
Preventive health care | |
Preventive dental visit vs. No preventive dental visit | |
Total Effect | 0.46 (0.42–0.51)*** |
Direct effect | 0.47 (0.42–0.51)*** |
Indirect effect | 0.98 (0.97-1.00) |
Percentage mediated (%) | 1.3 (-0.3 to 2.9) |
Health behaviour
Health status
Preventive health care
Mediation effect of HL in the relationship between income and health related outcomes
Odds Ratiob (95% CI) | |
---|---|
Health behaviour | |
Practice of physical activity vs. No practice of physical activity | |
Total Effect | 0.65 (0.58–0.72)*** |
Direct effect | 0.67 (0.59–0.74)*** |
Indirect effect | 0.97 (0.95–0.98)** |
Percentage mediated (%) | 5.8 (2.0 to 9.6)** |
Healthy diet vs. Unhealthy diet | |
Total Effect | 0.74 (0.63–0.85)*** |
Direct effect | 0.77 (0.65–0.88)*** |
Indirect effect | 0.96 (0.94–0.98)** |
Percentage mediated (%) | 10.9 (4.0 to 25.8)** |
Alcohol consumption (At least once a week vs. Less than once a week) | |
Total Effect | 0.50 (0.45–0.55)*** |
Direct effect | 0.51 (0.45–0.56)*** |
Indirect effect | 0.98 (0.97–0.99)** |
Percentage mediated (%) | 1.5 (0.2 to 2.8) |
Tobacco consumption (current smokers vs. No current smokers) | |
Total Effect | 1.70 (1.48–1.92)*** |
Direct effect | 1.66 (1.44–1.88)*** |
Indirect effect | 1.02 (1.01–1.04)** |
Percentage mediated (%) | 5.2 (1.3 to 9.1)** |
Health status | |
Good perceived health vs. Poor perceived health | |
Total Effect | 0.46 (0.40–0.52)*** |
Direct effect | 0.49 (0.42–0.53)*** |
Indirect effect | 0.95 (0.93–0.97)*** |
Percentage mediated (%) | 4.7 (2.5 to 6.9)** |
Poor mental health status | |
Total Effect | 1.54 (1.30–1.78)*** |
Direct effect | 1.48 (1.25–1.71)*** |
Indirect effect | 1.04 (1.02–1.06)** |
Percentage mediated (%) | 10.8 (3.7 to 17.9)** |
Preventive health care | |
Preventive dental visit vs. No preventive dental visit | |
Total Effect | 0.56 (0.50–0.62)*** |
Direct effect | 0.57 (0.51–0.63)*** |
Indirect effect | 0.98 (0.97–0.99)** |
Percentage mediated (%) | 2.1 (0.7 to 4.0)** |