Table 1 Antibiotic prescription rate of trials with baseline data and post-intervention measurements

Bjerrum et al. 2006

Spain

T0:

IG: n.s. (36%/29–44%/n.s.)

CG: not performed

T1:

IG: n.s. (24%/20–29%/n.s.)

CG: n.s. (32%/27–38%/n.s.)

T0:

n.s.

T1:

Δ (IG − CG) = − 12%

Difference in differences:

n.s.

T0:

n.s.

T1:

IG and CG: 0.67

IG:

Δ (T1 − T0) = − 12%

CG:

n.s.

Altiner et al. 2007

Germany

T0:

IG: n.s. (36.4%/n.s./n.s.)

CG: n.s. (54.7%/n.s./n.s.)

T1:

IG: n.s. (29.4%/n.s./n.s.)

Adjusted OR for IG: 0.58 (95% CI 0.43–0.78, p < 0.001)

CG: n.s. (59.4%/n.s./n.s.)

Adjusted OR for CG: 1.52 (95% CI 1.19–1.95, p = 0.001)

T2:

IG: n.s. (36.7%/n.s./n.s.)

Adjusted OR for IG: 0.72 (95% CI 0.54–0.97, p = 0.028)

CG: n.s. (64.8%/n.s./n.s.)

Adjusted OR for CG: 1.31 (95% CI 1.01–1.71, p = 0.044)

T0:

Δ (IG − CG) = − 18.3%

T1:

Δ (IG − CG) = − 30%

T2:

Δ (IG − CG) = − 28.1%

Difference in differences:

IG for T2: − 9.8%

T0:

IG and CG: 0.47

T1:

IG and CG: 0.28

T2:

IG and CG: 0.31

IG:

Δ (T1 − T0) = − 7%

Δ (T2 − T1) = − 7.3%

Δ (T2 − T0) = + 0.3%

CG:

Δ (T1 − T0) = + 4.7%

Δ (T2 − T1) = + 5.4%

Δ (T2 − T0) = + 10.1%

Gonzales et al. 2013

USA

T0:

IG 1: n.s. (80%/n.s./n.s.)

IG 2: n.s. (74%/n.s./n.s.)

CG: n.s. (72.5%/n.s./n.s.)

T1:

IG 1: n.s. (68.3%/n.s./n.s.)

IG 2: n.s. (60.7%/n.s./n.s.)

CG: n.s. (74.3%/n.s./n.s.)

T0: Δ (IG 2 − IG 1) = − 6%

Δ (IG 1 − CG) = + 7.5%

Δ (IG 2 − CG) = + 1.5%

T1:

Δ (IG 2 − IG 1) = − 7.6% (p = 0.67)

Δ (IG 1 − CG) = − 6% (p = 0.003)

Δ (IG 2 − CG) = − 13.6% (p = 0.01)

Difference in differences:

For IG 1: − 13.5%

For IG 2: − 15.1%

T0:

IG 1 and IG 2: 1.4

IG 1 and CG: 1.52

IG 2 and CG: 1.08

T1:

IG 1 and IG 2: 1.39

IG 1 and CG: 0.75

IG 2 and CG: 0.53

I 1:

Δ (T1 − T0) = − 11.7%

I 2:

Δ (T1 − T0) = − 13.3%

C:

Δ (T1 − T0) = + 1.8%

Gjelstad et al. 2013*

Norway

T0:

IG: n.s. (34.3%/31.8–36.9/n.s.)

CG: n.s. (35.2%/CI 32.8–37.7/n.s.)

T1:

IG: n.s. (32.8%/30.3–35.3/n.s.)

CG: n.s. (36.9%/34.2–39.7/n.s.)

T0:

Δ (IG − CG) = − 0.9%

T1:

Δ (IG − CG) = − 4.1%

Difference in differences:

IG: + 0.2%

T0:

IG and CG: 0.96

T1:

IG and CG: 0.83

IG:

Δ (T1 − T0) = − 1.52%

(95% CI − 2.85 to − 0.18, p = 0.027)

CG:

Δ (T1 − T0) = + 1.70

(95% CI 0.69–2.72, p = 0.002)

Andreeva et al. 2014

Russia

Subgroup of 13 physicians:

T0:

IG: 28/47 (59%/n.s./n.s.)

CG: 21/34 (62%/n.s./n.s.)

T1:

IG: 30/81 (37%/n.s./n.s.) CG: 44/62 (71%/n.s./n.s.)

T1 for all 18 GPs:

IG: n.s. (37.6%/n.s./n.s.)

CG: n.s. (58.9%/n.s./n.s.)

T2 for all 18 GPs:

IG: n.s. (40.6%/n.s./n.s.)

CG: n.s. (71.8%/n.s./n.s.)

T0:

Δ (IG − CG) = − 3%

T1 for subgroup of 13 GPs who also participated in baseline study:

Δ (IG − CG) = − 34%

T1 for all 18 GPs:

Δ (IG − CG) = − 21.3% (p = 0.006)

T2 for all 18 GPs:

Δ (IG − CG) = − 31.2% (p = 0.0001)

Difference in differences:

n.s.

T0 only for 13 GPs:

IG and CG: 0.91

T1 for subgroup of 13 GPs who also participated in baseline study:

IG and CG: 0.24

T1 for all 18 GPs:

IG and CG: 0.42

T2 for all 18 GPs:

IG and CG: 0.27

IG (subgroup of 13 GPs):

Δ (T1 − T0) = − 22%

CG (subgroup of 13 GPs):

Δ (T1 − T0) = + 9%

IG (all GPs):

Δ (T2 − T1) = + 4%

CG (all GPs):

Δ (T2 − T1) = + 12.9%

Gulliford et al. 2014

UK

T0:

IG: n.s. (53%/n.s./n.s.)

CG: n.s. (52%/n.s./n.s.)

T1:

IG: n.s. (52%/n.s./n.s.)

CG: n.s. (52%/n.s./n.s.)

T0:

Δ (IG − CG) = + 1%

T1:

Δ (IG − CG) = 0%

Adjusted mean difference (adjusted for pre-intervention value, as well as mean age and proportion of women at each practice): − 1.85% (95% CI 0.10–3.59%; p = 0.038)

Difference in differences:

IG: − 1%

T0:

IG and CG: 1.04

T1:

IG and CG: 1.00

IG:

Δ (T1 − T0) = − 1%

CG:

Δ (T1 − T0) = 0%

Little et al. 2013

Belgium, Spain, Wales, Great Britain, Poland, Netherlands

T0: 3742/6771 (55.3%/n.s./n.s.)

T1:

Abx prescription rates regarding study arms:

CG: 508/870 (58%/n.s./n.s.), OR = 1.00

Internet-based training for CRP-POCT: 368/1062 (35%/n.s./n.s.)

OR = 0.54 (95% CI 0.40–0.68; p < 0.001)

Internet-based CST: 476/1170 (41%/n.s./n.s.)

OR = 0.69 (95% CI 0.54–0.85; p < 0.001)

Internet-based CST + CRP-POCT: 366/1162 (32%/n.s./n.s.)

OR = 0.46 (95% CI 0.35–0.60; p < 0.001)

Abx prescription rates regarding factorial groups:

Cumulative non-CRP-training group: 984/2040 (48%/n.s./n.s.)

Cumulative CRP-training group: 734/2224 (33%/n.s./n.s.)

Cumulative non-CST group: 876/1932 (45%/n.s./n.s.)

Cumulative CST group: 842/2332 (36%/n.s./n.s.)

T1:

Δ (cumulative CRP group − cumulative non-CRP group): − 15%

Δ (cumulative CST group − cumulative non-CST group): − 9%

Difference in differences:

n.s.

T0: n.s.

T1:

Cumulative CRP-training group and cumulative non-CRP training group: 0.54 (95% CI 0.42–0.69, p < 0.0001)

Cumulative CRP-training group and cumulative communication training group: 0.88

Cumulative communication training group and cumulative non-communication training group: 0.69 (95% CI 0.54–0.87, p < 0.0001)

CG:

Δ (T1T0) = + 3%

Internet-based training for CRP-POCT:

Δ (T1 − T0) = − 20%

Internet-based communication training:

Δ (T1 − T0) = − 14%

Internet-based communication training + CRP-POCT:

Δ (T1 − T0) = − 23%

Cumulative non-CRP-training group:

Δ (T1 − T0) = − 7%

Cumulative CRP-training group:

Δ (T1 − T0) = − 22%

Cumulative no-CST group:

Δ (T1 − T0) = − 10%

Cumulative CST group:

Δ (T1 − T0) = − 19%

Meeker et al. 2016

USA

T0 for each study group:

IG 1: 1057/2132 (49.6%/47.5–51.7/n.s.)

IG 2: 497/1491 (33.3%/30.9–37.7/n.s.)

IG 3: 433/1236 (35.0%/32.4–37.7/n.s.)

IG 1 + 2: 702/1977 (35.5%/33.4–37.6/n.s.)

IG 1 + 3: 368/1511 (24.4%/22.2–26.5/n.s.)

IG 2 + 3: 782/2362 (33.1%/31.2–35.0/n.s.)

IG 1 + 2 + 3: 558/2178 (25.6%/23.8–37.5/n.s.)

CG: 692/1866 (37.1%/34.9–39.3/n.s.)

T1 for each study group:

IG 1: 722/2388 (30.2%/28.4–32.1/n.s.)

IG 2: 324/1979 (16.4%/14.7–18.0/n.s.)

IG 3: 311/1620 (19.2%/17.3–21.1/n.s.)

IG 1 + 2: 341/2131 (16.0%/14.5–17.6/n.s.)

IG 1 + 3: 139/2014 (6.9%/5.8–8.0/n.s.)

IG 2 + 3: 340/2240 (15.2%/13.7–16.7/n.s.)

IG 1 + 2 + 3: 249/2492 (10.0%/8.8–11.2/n.s.)

CG: 502/2095 (24.0%/22.1–25.8/n.s.)

T0:

Δ (IG 1 − CG): + 12.5%

Δ (IG 2 − CG): − 3.8%

Δ (IG 3 − CG): − 2.1%

Δ (IG 1 − IG 2): + 16.3%

Δ (IG 1 − IG 3): + 14.6%

Δ (IG 2 − IG 3): − 1.7%

T1:

Δ (IG 1 − CG): + 6.2%

Δ (IG 2 − CG): − 7.6%

Δ (IG 3 − CG): − 4.8%

Δ (IG 1 − IG 2): + 13.8%

Δ (IG 1 − IG 3): + 11%

Δ (IG 2 − IG 3): − 2.8%

Difference in differences:

IG 1: − 6.3%

IG 2: − 3.8%

IG 3: − 2.7%

IG 1 + 2: − 6.4%

IG 1 + 3: − 4.4%

IG 2 + 3: − 4.8%

IG 1 + 2 + 3: − 2.5%

T0:

IG 1 and CG: 1.67

IG 2 and CG: 0.85

IG 3 and CG: 0.91

IG 1 and IG2: 1.97

IG 1 and IG 3: 1.83

IG 2 and IG 3: 0.93

T1:

IG 1 and CG: 1.37

IG 2 and CG: 0.62

IG 3 and CG: 0.75

IG 1 and IG 2: 2.21

IG 1 and IG 3: 1.82

IG 2 and IG 3: 0.83

IG 1:

Δ (T1 − T0) = − 19.4%

IG 2:

Δ (T1 − T0) = − 16.9%

IG 3:

Δ (T1 − T0) = − 15.8%

IG 1 + 2:

Δ (T1 − T0) = − 19.5%

IG 1 + 3:

Δ (T1 − T0) = − 17.5%

IG 2 + 3:

Δ (T1 − T0) = − 17.9%

IG 1 + 2 + 3:

Δ (T1 − T0) = − 15.6%

CG:

Δ (T1 − T0) = − 13.1%

Adjusted analysis (hierarchical regression model) for factorial study groups:

CG:

Δ (T1 − T0) = − 11.0%

IG 1:

Δ (T1 − T0) = − 16%

IG 2:

Δ (T1 − T0) = − 18.1%

IG 3:

Δ (T1 − T0) = − 16.3%