Table 3.

Multilevel logistic regression: complete case analysis and analysis with multiple imputation showing all the variables entered into the model and association with antibiotic prescription

VariableComplete caseMultiple imputation
Odds ratio95% CIP-valueOdds ratio95% CIP-value
Signs, symptoms, and past history
  Runny or blocked nose1.70.8 to 3.40.1601.50.9 to 2.80.140
  Sore throat1.10.6 to 1.90.8501.10.7 to 1.90.610
  Earache or holding ear0.50.3 to 1.00.0400.70.4 to 1.10.140
  Cough0.70.3 to 1.40.2800.80.5 to 1.50.540
  Difficulty breathing0.40.2 to 0.80.0200.50.3 to 0.80.009
  Hot/feverish1.50.8 to 2.90.1901.71.0 to 2.80.060
  Rash0.80.3 to 2.10.7100.80.4 to 1.80.640
  Irritable/grouchy1.10.6 to 2.30.7101.10.6 to 2.00.680
  Clinginess/needing extra care0.80.4 to 1.80.5700.80.4 to 1.50.490
  Low energy/tired or lost interest in playing0.50.3 to 1.10.0800.60.3 to 1.00.050
  Poorer sleep2.71.5 to 5.00.0012.11.3 to 3.50.004
  Poorer feeding/poorer appetite1.91.0 to 3.60.0601.20.7 to 2.00.570
  Diarrhoea0.70.4 to 1.40.3300.70.4 to 1.20.220
  Abdominal pain0.80.4 to 1.50.4400.80.5 to 1.50.560
  Smelly urine1.00.5 to 2.00.9900.80.5 to 1.60.600
  Dark or cloudy urine1.90.8 to 4.20.1301.60.8 to 3.30.170
  Past history of eczema1.40.7 to 2.60.3501.50.9 to 2.50.170
Examination findings
  Abnormal ear examination6.52.5 to 17.2<0.0015.92.7 to 12.8<0.001
  Abnormal throat examination2.21.1 to 4.50.0302.31.2 to 4.20.009
  Abnormal chest examination13.65.8 to 32.2<0.00113.46.5 to 27.7<0.001
  Rash (on examination)1.60.6 to 4.40.3902.21.0 to 5.00.060
GP working diagnosis (URTI reference)
  LRTI9.53.7 to 24.5<0.0016.73.0 to 14.8<0.001
  Tonsillitis/sore throat119.328.2 to 504.6<0.001109.530.5 to 392.8<0.001
  Ear infection26.57.4 to 95.7<0.00121.67.3 to 63.7<0.001
  UTI12.74.4 to 36.5<0.00113.15.5 to 31.0<0.001
  Viral illness0.50.2 to 1.50.2100.40.2 to 1.00.060
  Other2.10.8 to 5.40.1201.90.9 to 4.10.110
  No GP diagnosis1.50.2 to 11.40.6901.20.4 to 3.90.810
Parent/carer impression scale (normal/not unwell reference)
  Slightly unwell0.90.3 to 3.10.8700.60.2 to 1.60.320
  Moderately, very, or severely unwell1.20.3 to 4.60.7601.00.3 to 2.70.960
Clinician impression scale (normal/not unwell reference)
  Slightly unwell2.00.9 to 4.70.1102.11.0 to 4.30.050
  Moderately, very, or severely unwell4.01.4 to 11.40.0094.61.9 to 11.00.001
Temperature on examination0.80.6 to 1.20.3000.80.6 to 1.20.260
Non-clinical factors
  Age, years1.31.1 to 1.70.0101.31.0 to 1.50.010
  Sex (boy) (girl reference)1.00.6 to 1.70.9000.90.6 to 1.40.590
  • P-values < 0.05 in bold. LRTI = lower respiratory tract infection. URTI = upper respiratory tract infection. UTI = urinary tract infection.