Article Figures & Data
Figures
- Figure 1.
Monthly number of visits and visits with antibiotic prescriptions, and monthly proportions of visits with antibiotic prescriptions, from 2005 to 2011 in British Columbia: The spike in RTI visits at the end of 2009, and related decrease in proportion of visits associated with a prescription, is likely attributable to the H1N1 influenza pandemic.
RTI—respiratory tract infection.
- Figure 2.
Histogram of proportion of pediatric RTI visits associated with an antibiotic prescription, per physician, between 2005 and 2011: Frequencies are weighted by the total number of RTI visits.
RTI—respiratory tract infection.
Tables
VARIABLE FULL DATA SET* SAMPLE OF 1 VISIT PER CHILD* ALL VISITS (N = 2 996 186)† ASSOCIATED WITH AN ANTIBIOTIC PRESCRIPTION (N = 834 673)‡ NOT ASSOCIATED WITH AN ANTIBIOTIC PRESCRIPTION (N = 2 161 513)‡ ALL VISITS (N = 671 342)† ASSOCIATED WITH AN ANTIBIOTIC PRESCRIPTION (N = 183 118)‡ NOT ASSOCIATED WITH AN ANTIBIOTIC PRESCRIPTION (N = 488 224)‡ Overall population, % 100.0 27.9 72.1 100.0 27.3 72.7 Year, % • 2005 11.3 30.3 69.7 13.2 31.6 68.4 • 2006 15.4 29.4 70.6 16.2 30.6 69.4 • 2007 14.7 28.5 71.6 13.7 28.9 71.1 • 2008 14.1 28.8 71.2 12.6 28.4 71.6 • 2009 16.9 22.9 77.2 16.1 21.2 78.9 • 2010 13.1 28.0 72.0 12.2 25.8 74.3 • 2011 14.6 28.6 71.5 16.1 25.4 74.6 Patient-level factors Patient sex • Female, % 47.5 27.9 72.1 48.9 27.3 72.7 • Male, % 52.5 27.8 72.2 51.2 27.3 72.7 • Missing, n 2 NA NA 1 NA NA Median (IQR) patient age, y 4 (2–9) 6 (3–10) 4 (1–8) 6 (2–11) 8 (4–12) 5 (1–10) • Missing, n 2 NA NA 2 NA NA Follow-up RTI visit,§ % 14.0 24.6 75.5 7.9 24.3 75.8 QAIPPE • 1 (lowest), % 22.2 28.6 71.4 20.4 27.6 72.4 • 2, % 22.7 28.7 71.3 20.9 27.8 72.2 • 3, % 20.0 27.6 72.4 20.5 27.3 72.7 • 4, % 18.2 26.9 73.1 20 26.9 73.1 • 5 (highest), % 15.7 27.1 72.9 18.2 26.7 73.3 • Missing, n 38 224 NA NA 9157 NA NA Diabetes, % 0.2 33.1 66.9 0.2 33.3 66.7 Asthma, % 12.4 31.5 68.5 8.1 31.1 68.9 Cystic fibrosis, % 0.2 18.6 81.4 0.1 17.7 82.3 Immune deficiency, % 0.2 30.2 69.8 0.2 28.7 71.3 Chronic liver disease, % < 0.1 27.8 72.2 0.0 26.4 73.6 Congestive heart failure, % < 0.1 27.2 72.8 0.0 22.9 77.1 COPD, % 0.5 31.5 68.5 0.3 31.4 68.7 Chronic kidney disease, % 0.1 28.7 71.4 0.1 28.5 71.6 Recent antibiotic use,‖ % 9.1 24.5 75.5 9.4 24.1 75.9 Median (IQR) ADG sum 4 (2–5) 4 (2–5) 4 (2–5) 3 (2–5) 3 (2–4) 3 (2–5) • Missing, n 9 NA NA 2 NA NA Visits in past 3 y with this physician, % • 0 36.6 28.6 71.4 46.8 28.7 71.3 • ≤ 30 (but > 0) 30.2 28.6 71.4 25.5 27.9 72.1 • > 30 33.2 26.3 73.7 27.8 24.4 75.6 Median (IQR) no. of different GPs seen in past 3 y 5 (3–7) 5 (3–8) 5 (3–7) 4 (2–6) 4 (2–6) 4 (2–6) Season, % • Mar–May 24.2 29.1 70.9 24.5 29.0 71.0 • Jun–Aug 15.0 29.5 70.5 14.5 29.7 70.3 • Sep–Nov 29.3 25.4 74.6 28.8 24.0 76.0 • Dec–Feb 31.5 28.4 71.6 32.3 27.8 72.3 Physician-level factors Physicians, n 6404 NA NA 6148 NA NA Physician sex • Female, % 27.7 23.5 76.6 28.3 23.0 77.0 • Male, % 72.3 29.5 70.5 71.7 28.9 71.1 • Missing, n 10 398 NA NA 1910 NA NA Specialty, % • Emergency medicine physician 0.6 25.1 74.9 0.7 25.2 74.8 • Pediatrician 2.9 11.2 88.8 2.4 12.8 87.2 • Other 0.8 41.8 58.2 0.7 40.7 59.3 • GP 95.7 28.3 71.7 96.2 27.6 72.5 Visits for RTIs in the past 30 d, % • None 0.6 20.4 79.6 0.7 21.0 79.0 • ≤ 2.5 5.7 21.7 78.3 6.9 22.1 77.9 • > 2.5–5 14.7 24.4 75.6 16.8 24.7 75.3 • > 5–7.5 16.5 26.0 74.0 17.8 26.2 73.8 • > 7.5–10 14.8 27.9 72.2 14.8 27.4 72.6 • > 10–15 22.1 29.9 70.1 20.6 29.3 70.7 • > 15–20 14.0 31.9 68.1 12.2 30.9 69.1 • > 20 11.7 29.4 70.6 10.2 28.7 71.3 Medical school graduation location • Canada, % 62.1 24.3 75.8 64.1 23.8 76.2 • International, % 37.9 33.8 66.2 36.0 33.4 66.6 • Missing, n 70 648 NA NA 15 683 NA NA Daily patient volume,¶ % • 1st quartile (< 28 visits) 22.8 23.2 76.9 25.3 23.3 76.7 • 2nd quartile (28–37 visits) 24.9 26.4 73.6 26.6 26.2 73.8 • 3rd quartile (38–48 visits) 26.0 28.9 71.1 25.7 28.7 71.3 • 4th quartile (> 48 visits) 26.3 32.3 67.7 22.4 31.4 68.6 Years since medical school graduation • 0–5, % 4.6 21.8 78.2 5.2 20.8 79.3 • 6–10, % 9.3 22.1 77.9 9.8 22.4 77.6 • 11–15, % 13.0 24.0 76.0 13.4 24.3 75.7 • 16–20, % 18.5 26.9 73.1 18.2 27.0 73.1 • 21–25, % 16.8 28.7 71.3 16.5 27.7 72.3 • 26–30, % 13.9 30.0 70.0 13.7 29.3 70.7 • 31–35, % 11.9 30.7 69.3 11.6 29.7 70.3 • 36–40, % 7.4 30.7 69.3 7.2 29.7 70.3 • > 40, % 4.7 39.1 60.9 4.5 37.9 62.1 • Missing, n 4032 NA NA 1050 NA NA No. of RTIs seen in the past y, % • 1st quartile (≤ 248) 20.4 20.8 79.2 24.8 21.5 78.5 • 2nd quartile (249–490) 22.2 25.6 74.5 25.1 25.9 74.1 • 3rd quartile (491–972) 25.2 28.2 71.8 25.0 28.5 71.5 • 4th quartile (≥ 973) 32.2 33.7 66.4 25.0 33.2 66.8 Regional-level factors Median (IQR) proportion of LHA population aged > 65 y 0.13 (0.10–10.15) 0.13 (0.10–0.15) 0.13 (0.11–0.15) 0.13 (0.11–0.16) 0.13 (0.10–0.16) 0.13 (0.11–0.16) Median (IQR) proportion of LHA population aged < 15 y 0.18 (0.16–0.21) 0.19 (0.17–0.22) 0.18 (0.16–0.21) 0.18 (0.16–0.21) 0.19 (0.16–0.21) 0.18 (0.16–0.21) Median (IQR) age of LHA population, y 39 (36–41) 38 (35–41) 39 (37–41) 39 (37–42) 39 (37–41) 39 (37–42) Health authority • Interior, % 11.8 27.8 72.2 14.5 28.0 72.1 • Fraser, % 46.3 29.6 70.4 41.3 28.5 71.5 • Vancouver Coastal, % 23.2 22.4 77.6 22.3 21.9 78.1 • Vancouver Island, % 12.2 26.4 73.6 14.3 26.5 73.5 • Northern, % 6.5 37.5 62.5 7.5 36.6 63.4 • Missing, n 4689 NA NA 1251 NA NA Median (IQR) 28-d moving average apparent temperature, °C 4.73 (0.57–11.76) 4.62 (0.33–12.14) 4.77 (0.66–11.57) 4.49 (0.36–11.50) 4.42 (0.17–12.14) 4.52 (0.43–11.24) ADG—aggregated diagnosis group, COPD—chronic obstructive pulmonary disease, IQR—interquartile range, LHA—local health area, NA—not applicable, QAIPPE—Quintile of Annual Income Per Person Equivalent, RTI—respiratory tract infection.
↵* Not all percentages add to 100 owing to rounding.
↵† Overall values.
↵‡ Within-category values.
↵§ A follow-up visit is any visit within 14 d of another RTI visit.
↵‖ Recent antibiotic use is any antibiotic prescription within the past 6 mo.
↵¶ Daily patient volume is the total number of claims billed on the RTI visit day.
- Table 2.
Generalized linear mixed model of antibiotic prescription for pediatric RTIs: A) Effect estimates and B) measures of model fit and variance.
A) EFFECT EMPTY MODEL BASIC MODEL WITH YEAR ONLY WITH PATIENT COVARIATES WITH PATIENT AND PHYSICIAN COVARIATES WITH PATIENT, PHYSICIAN, AND REGIONAL COVARIATES Random effect, variance (SE) Physician 0.96 (0.023) 0.95 (0.022) 0.91 (0.011) 0.78 (0.019) 0.76 (0.019) Fixed effects, OR (95% CI) Constant term 0.27 (0.26–0.27) 0.35 (0.34–0.36) 0.18 (0.17–0.18) 0.10 (0.09–0.11) 0.10 (0.08–0.12) Year (reference: 2005) • 2006 0.93 (0.91–0.95) 0.94 (0.92–0.96) 0.91 (0.88–0.93) 0.90 (0.88–0.92) • 2007 0.89 (0.87–0.91) 0.93 (0.91–0.95) 0.88 (0.86–0.90) 0.87 (0.85–0.89) • 2008 0.85 (0.83–0.87) 0.92 (0.90–0.94) 0.87 (0.85–0.89) 0.86 (0.84–0.88) • 2009 0.58 (0.57–0.60) 0.61 (0.60–0.63) 0.58 (0.56–0.59) 0.57 (0.56–0.59) • 2010 0.76 (0.74–0.78) 0.92 (0.90–0.94) 0.83 (0.81–0.86) 0.83 (0.81–0.85) • 2011 0.75 (0.73–0.77) 0.94 (0.92–0.96) 0.86 (0.83–0.88) 0.85 (0.82–0.87) Season (reference: Jun–Aug) • Mar–May 0.98 (0.97–1.00) 0.99 (0.97–1.00) 1.05 (1.03–1.07) 0.99 (0.97–1.02) • Sep–Nov 0.80 (0.79–0.82) 0.80 (0.79–0.82) 0.86 (0.85–0.88) 0.80 (0.77–0.82) • Dec–Feb 0.99 (0.97–1.00) 0.96 (0.94–0.98) 1.06 (1.04–1.09) 0.95 (0.92–0.98) Patient sex (reference: male) • Female 0.97 (0.96–0.98) 0.97 (0.96–0.98) 0.97 (0.96–0.98) Patient age (per y increase) 1.08 (1.08–1.08) 1.08 (1.08–1.08) 1.08 (1.08–1.08) Follow-up RTI visit 0.98 (0.96–1.01) 0.97 (0.95–1.00) 0.97 (0.95–1.00) QAIPPE (reference: 1) • 2 1.00 (0.98–1.02) 1.00 (0.98–1.02) 1.00 (0.98–1.02) • 3 1.01 (0.99–1.03) 1.01 (0.99–1.03) 1.01 (0.99–1.03) • 4 1.02 (1.00–1.04) 1.02 (1.00–1.05) 1.02 (1.00–1.04) • 5 1.03 (1.01–1.05) 1.04 (1.02–1.06) 1.04 (1.02–1.06) Diabetes 1.08 (0.95–1.22) 1.05 (0.93–1.19) 1.05 (0.93–1.19) Asthma 1.06 (1.04–1.08) 1.06 (1.04–1.08) 1.06 (1.04–1.08) Cystic fibrosis 0.96 (0.80–1.16) 0.97 (0.80–1.18) 0.97 (0.80–1.18) Immune deficiency 0.92 (0.80–1.07) 0.92 (0.79–1.06) 0.92 (0.79–1.06) Chronic liver disease 1.07 (0.74–1.56) 1.03 (0.70–1.52) 1.00 (0.68–1.48) Congestive heart failure 1.30 (0.88–1.92) 1.12 (0.75–1.69) 1.12 (0.74–1.68) COPD 0.87 (0.78–0.98) 1.14 (1.02–1.29) 1.15 (1.02–1.29) Chronic kidney disease 0.90 (0.72–1.13) 1.12 (0.89–1.40) 1.12 (0.90–1.40) Recent antibiotic use 0.85 (0.83–0.87) 0.86 (0.84–0.88) 0.86 (0.84–0.88) ADG sum 0.97 (0.97–0.97) 0.97 (0.97–0.97) 0.97 (0.97–0.97) Visits in past 3 y with this physician, % (reference: > 30) • 0 1.20 (1.18–1.22) 1.21 (1.19–1.24) 1.21 (1.19–1.24) • ≤ 30 (but > 0) 1.07 (1.05–1.09) 1.07 (1.05–1.09) 1.07 (1.05–1.09) No. of different GPs seen in past 3 y 1.02 (1.02–1.02) 1.02 (1.02–1.02) 1.02 (1.02–1.02) Physician sex (reference: male) • Female 0.89 (0.84–0.94) 0.91 (0.86–0.96) Specialty (reference: GP) • Emergency medicine physician 0.79 (0.61–1.02) 0.79 (0.62–1.02) • Pediatrician 0.47 (0.41–0.55) 0.48 (0.42–0.56) • Other 0.88 (0.72–1.06) 0.89 (0.73–1.07) Visits for RTIs in the past 30 d, % (reference: > 20) • None 1.34 (1.21–1.49) 1.36 (1.23–1.51) • ≤ 2.5 1.42 (1.35–1.49) 1.45 (1.38–1.52) • > 2.5–5 1.40 (1.34–1.45) 1.42 (1.36–1.48) • > 5–7.5 1.32 (1.27–1.37) 1.33 (1.29–1.38) • > 7.5–10 1.25 (1.21–1.30) 1.26 (1.22–1.31) • > 10–15 1.21 (1.17–1.25) 1.22 (1.18–1.25) • > 15–20 1.13 (1.10–1.16) 1.13 (1.10–1.16) Medical school graduation location (reference: Canada) • International 1.77 (1.68–1.88) 1.73 (1.63–1.83) Daily patient volume (reference: 1st quartile [< 28 visits]) • 2nd quartile (28–37 visits) 0.99 (0.97–1.01) 0.99 (0.98–1.01) • 3rd quartile (38–48 visits) 0.97 (0.95–0.99) 0.97 (0.95–0.99) • 4th quartile (> 48 visits) 0.94 (0.92–0.96) 0.94 (0.92–0.97) Years since medical school graduation (reference: 0–5) • 6–10 0.98 (0.93–1.03) 0.99 (0.94–1.04) • 11–15 1.07 (1.01–1.14) 1.08 (1.02–1.15) • 16–20 1.15 (1.08–1.22) 1.16 (1.09–1.24) • 21–25 1.21 (1.13–1.29) 1.23 (1.15–1.31) • 26–30 1.29 (1.21–1.39) 1.32 (1.23–1.41) • 31–35 1.32 (1.23–1.42) 1.35 (1.26–1.46) • 36–40 1.36 (1.25–1.47) 1.39 (1.29–1.51) • > 40 1.41 (1.28–1.56) 1.46 (1.33–1.61) No. of RTIs seen in the past y (reference: 1st quartile [≤ 248]) • 2nd quartile (249–490) 1.10 (1.07–1.13) 1.11 (1.08–1.14) • 3rd quartile (491–972) 1.17 (1.12–1.21) 1.19 (1.15–1.23) • 4th quartile (≥ 973) 1.27 (1.21–1.33) 1.31 (1.25–1.37) LHA population aged > 65 y (per 10%) 0.99 (0.98–1.00) LHA population aged < 15 y (per 10%) 1.12 (1.06–1.17) Median age of LHA population (centred on mean) 1.19 (1.11–1.27) Health authority (reference: Vancouver Coastal) • Interior 1.07 (1.02–1.13) • Fraser 1.00 (0.97–1.03) • Vancouver Island 1.03 (0.98–1.08) • Northern 1.20 (1.13–1.28) 28-d moving average apparent temperature 0.99 (0.99–0.99) B) MEASURE EMPTY MODEL BASIC MODEL WITH YEAR ONLY WITH PATIENT COVARIATES WITH PATIENT AND PHYSICIAN COVARIATES WITH PATIENT, PHYSICIAN, AND REGIONAL COVARIATES Observations used, n 671 342 671 342 662 202 645 815 645 094 AIC 616 216.2 692 274.7 666 759.5 648 692.3 647 788.8 ICC,* % 22.6 22.4 21.6 19.2 18.8 MOR 2.55 2.53 2.48 2.33 2.30 PCV (relative to intercept-only model) at level of physician, % NA 1.49 5.86 18.55 20.82 PCV (relative to previous model) at level of physician, % NA 1.49 4.44 13.48 2.78 ADG—aggregated diagnosis group, AIC—Akaike information criterion, COPD—chronic obstructive pulmonary disease, ICC—intraclass correlation, IQR—interquartile range, LHA—local health area, MOR—median odds ratio, NA—not applicable, OR—odds ratio, PCV—percent change in variance, QAIPPE—Quintile of Annual Income Per Person Equivalent, RTI—respiratory tract infection.
↵* ICC is the proportion of total variance attributable to between-physician differences.
