Skip to main content

Table 3 The results of survival analysis, negative binomial regression, and regression for dental care visits and expenditures including both patient and regional characteristics

From: The differences in healthcare utilization for dental caries based on the implementation of water fluoridation in South Korea

Variables Dental care visitsa Only patient with dental care visit
Number of dental care visitsb Dental care costs (KRW)c
HR 95 % CI P-value β SE P-value β SE P-value
Regional variables
Water fluoridation
 Yes 0.949 0.928 0.971 <.0001 −0.029 0.014 0.0431 0.008 0.021 0.7097
 No 1.000 – – – Ref – – Ref – –
Period from implementation of water fluoridation 0.998 0.995 1.001 0.2302 −0.003 0.001 0.0177 −0.006 0.002 0.0024
Number of dentists per 1,000 residents 1.007 0.975 1.041 0.6700 −0.045 0.016 0.0068 −0.026 0.024 0.2812
Financial independence rate of local government 0.999 0.999 0.999 <.0001 −0.003 0.000 <.0001 −0.003 0.000 <.0001
Individual variables
Sex
 Male 0.795 0.788 0.801 <.0001 −0.051 0.004 <.0001 −0.071 0.005 <.0001
 Female 1.000 – – – Ref – – Ref – –
Age (Years)
 -19 4.835 4.695 4.979 <.0001 0.408 0.010 <.0001 0.662 0.013 <.0001
 20–29 3.069 2.977 3.163 <.0001 0.064 0.011 <.0001 0.020 0.014 0.1451
 30–39 2.466 2.392 2.542 <.0001 −0.073 0.011 <.0001 −0.134 0.014 <.0001
 40–49 2.502 2.427 2.579 <.0001 −0.069 0.011 <.0001 −0.101 0.013 <.0001
 50–59 2.531 2.452 2.613 <.0001 −0.022 0.011 0.0487 −0.030 0.014 0.0316
 60–69 2.044 1.978 2.112 <.0001 0.033 0.012 0.0045 0.055 0.016 0.0004
  < 70 1.000 – – – Ref – – Ref – –
Income (percentile)
 -10 % (low) 0.751 0.736 0.767 <.0001 0.003 0.009 0.7721 −0.085 0.013 <.0001
 11–20 % 0.751 0.736 0.767 <.0001 −0.004 0.009 0.6797 −0.094 0.013 <.0001
 21–30 % 0.762 0.747 0.777 <.0001 −0.004 0.009 0.6740 −0.099 0.013 <.0001
 31–40 % 0.770 0.756 0.784 <.0001 −0.026 0.008 0.0018 −0.121 0.012 <.0001
 41–50 % 0.805 0.790 0.819 <.0001 0.006 0.008 0.4173 −0.069 0.012 <.0001
 51–60 % 0.835 0.821 0.850 <.0001 0.011 0.008 0.1536 −0.045 0.012 0.0001
 61–70 % 0.880 0.866 0.895 <.0001 0.028 0.007 0.0002 −0.007 0.011 0.5510
 71–80 % 0.916 0.901 0.931 <.0001 0.030 0.007 <.0001 0.025 0.011 0.0267
 81–90 % 0.943 0.928 0.959 <.0001 0.023 0.007 0.0007 0.025 0.011 0.0190
  + 91 % (high) 1.000 – – – Ref – – Ref – –
Types of insurance coverage
 Medical Aid 0.410 0.396 0.425 <.0001 −0.573 0.018 <.0001 −0.956 0.017 <.0001
 NHI, self-employed insured 0.872 0.865 0.879 <.0001 −0.033 0.004 <.0001 −0.097 0.006 <.0001
 NHI, employee insured 1.000 – – – Ref – – Ref – –
Year of baseline/Index year
 2003 1.000 – – – Ref – – Ref – –
 2004 1.052 1.026 1.079 <.0001 −0.015 0.003 <.0001 −0.126 0.013 <.0001
 2005 1.126 1.092 1.162 <.0001 −0.018 0.003 <.0001 −0.102 0.013 <.0001
 2006 1.124 1.089 1.160 <.0001 −0.017 0.003 <.0001 −0.108 0.013 <.0001
 2007 1.143 1.104 1.183 <.0001 0.128 0.004 <.0001 −0.037 0.013 0.0037
 2008 1.104 1.065 1.144 <.0001 0.209 0.004 <.0001 0.016 0.013 0.2238
 2009 1.038 0.997 1.080 0.0710 0.192 0.004 <.0001 0.000 0.013 0.9752
 2010 0.974 0.931 1.018 0.2418 0.176 0.004 <.0001 −0.073 0.013 <.0001
 2011 0.736 0.695 0.779 <.0001 0.163 0.004 <.0001 0.079 0.013 <.0001
 2012 0.483 0.445 0.523 <.0001 0.157 0.004 <.0001 0.045 0.013 0.0007
 2013 0.304 0.265 0.350 <.0001 0.149 0.004 <.0001 0.091 0.014 <.0001
Pre-dental care costs (per 1,000 KRW)      0.001 0.000 <.0001 0.004 0.000 <.0001
Number of pre-dental care      0.183 0.004 <.0001 0.309 0.009 <.0001
Dentofacial anomalies
 Yes 21.614 17.417 26.821 <.0001 1.925 0.022 <.0001 8.832 0.037 <.0001
 No 1.000 – – – Ref – – Ref – –
Disorders of toothe development and eruption
 Yes 16.465 15.392 17.614 <.0001 1.563 0.008 <.0001 8.348 0.012 <.0001
 No 1.000 – – – Ref – – Ref – –
  1. aThe survival analysis using cox proportional hazard models was applied to investigate the association with risk of dental care visits during study period
  2. bThe negative binomial regression using GEE models was performed for patients who had experienced a dental care visit at least once per year to investigate the associations with dental care visits
  3. cThe regression using GEE models was performed for patients who had experienced a dental care visit at least once per year to investigate the associations with dental care cost
Back to article page