Table 2.

Hazard ratios for re-infection comparing two-stage revision versus one-stage revision adjusted progressively for risk factors

Model	Hazard ratio (95% CI)	P value	Hazard ratio (95% CI)	P value
	1038 participants (113 re-infections) with available data		439 participants (41 re-infections) with available data
Model 1	1.69 (0.58–4.98)	0.338	1.65 (0.44–6·20)	0.460
Model 2	1.70 (0.58–5.00)	0.332	1.66 (0.44–6·24)	0.454
Model 3	1.33 (0.48–3.69)	0.583	1.57 (0.45–5·51)	0.484
Model 4	–	–	1.59 (0.39–6·55)	0.520
Model 5	–	–	1.71 (0.39–7·50)	0.479

Model 1: adjusted for age

Model 2: model 1 plus sex

Model 3: model 2 plus previous hip surgery other than index surgery (yes/no)

Model 4: model 3 plus Charlson comorbidity index (no previous disease/one or two disease categories/more than two disease categories)

Model 5: model 4 plus difficult to treat organism (yes/no)