Revision of primary THR illustrated in section 1; 5 and 10 year values in table 2 (main text)  Probability of two stage Exp/(1+exp) where = -0.938 + 0.538*Male +0.0052*Age – revision 0.0017*Time-2 – 0.0298*Time2 – 0.786*Cemless – 0.296*Hybrid  Failure in year of revision 1-exp(-exp)) where = -2.932 + 0.139*Male – 0.0281*Age  Revision of revised THR after 1-exp(-exp)) where = -4.520 + 0.139*Male – 0.0580*Age – first year 0.0017*Age2  30d mortality after primary THR 1/(1+exp) where = –7.523 + 0.727*Male + 0.1007*Age + 0.0012*Age2  Death in year of revision 1/(1+exp) where = -2.932 + 0.258*Male + 0.1140*Age + surgery 0.0011*Age2 Death in other years ONS value multiplied by (0.803 + 0.004*Male + 0.0259*Age – 0.0159*Age2 + 0.702*Time – 0.0711*Time*Age Cost of Primary THR Values tabulated in Table 2 (main text) *Age is patient age, Male is 1 for male, 0 for female, Time is time in years after surgery, LoS is length of stay in days, Cemless indicates a cementless prosthesis, Hybrid indicates a hybrid prosthesis. Table 1A Markov model parameters
Revision of primary THR illustrated in section 1; 5 and 10 year values in table 2 (main text) Probability of two stage revision Exp/(1+exp) where  = -0.938 + 0.538*Male +0.0052*Age – 0.0017*Time-2 – 0.0298*Time2 – 0.786*Cemless – 0.296*Hybrid Failure in year of revision 1-exp(-exp)) where  = -2.932 + 0.139*Male – 0.0281*Age Revision of revised THR after first year 1-exp(-exp)) where  = -4.520 + 0.139*Male – 0.0580*Age – 0.0017*Age2 30d mortality after primary THR 1/(1+exp) where  = –7.523 + 0.727*Male + 0.1007*Age + 0.0012*Age2 Death in year of revision surgery 1/(1+exp) where  = -2.932 + 0.258*Male + 0.1140*Age + 0.0011*Age2 Death in other years ONS value multiplied by (0.803 + 0.004*Male + 0.0259*Age – 0.0159*Age2 + 0.702*Time – 0.0711*Time*Age Cost of Primary THR Values tabulated in Table 2 (main text) *Age is patient age, Male is 1 for male, 0 for female, Time is time in years after surgery, LoS is length of stay in days, Cemless indicates a cementless prosthesis, Hybrid indicates a hybrid prosthesis. Table 1A Markov model parameters