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Table 2 Results of controlled interrupted segmented regression of time series

From: Impact of removal and restriction of me-too medicines in a hospital drug formulary on in- and outpatient drug prescriptions: interrupted time series design with comparison group

 Pre-intervention trendPost-intervention
Immediate impact of the formulary changeChange in trend after the formulary change
Coefficient95% confidence intervalCoefficient95% confidence intervalCoefficient95% confidence interval
DDD/TID
 Total low molecular weight heparins− 0.00368− 0.01652 to 0.00916− 0.22475− 0.84762 to 0.398120.03792− 0.00526 to 0.08110
 Enoxaparina− 0.02868*− 0.03783 to − 0.019530.83432*0.40110 to 1.267540.06759*0.03701 to 0.09817
 Bemiparinb0.00739*0.00165 to 0.01313− 0.44664*− 0.70761 to − 0.18567− 0.02817*− 0.04681 to − 0.00953
 Tinzaparinc0.013880*0.00651 to 0.02125− 0.26654*− 0.45942 to − 0.07366− 0.00187− 0.01381 to 0.01007
 Dalteparinb− 0.00071*− 0.00136 to − 0.00006− 0.02773*− 0.05092 to − 0.004540.00141− 0.00012 to 0.00294
 Nadroparind0.00062*0.00005 to 0.001190.00459− 0.01871 to 0.02789− 0.00043− 0.00200 to 0.00114
DDD/100 stays and day
 Total low molecular weight heparins− 0.27284− 0.91964 to 0.3739614.51816− 13.64694 to 42.68326− 1.80935− 3.80400 to 0.18530
 Enoxaparina− 0.40854− 1.01540 to 0.1983241.83919*15.89330 to 67.78508− 0.20613− 2.10147 to 1.68921
 Bemiparinb− 0.24035*− 0.42506 to − 0.05564− 8.06595*− 15.39245 to − 0.73945− 0.88081*− 1.42010 to − 0.34152
 Tinzaparinc0.51274*0.33291 to 0.69257− 12.50797*− 16.85966 to − 8.15628− 0.51714*− 0.82116 to − 0.21312
 Dalteparinb−0.06482*− 0.09016 to − 0.03948− 1.25262*− 2.15101 to − 0.354230.04139− 0.01988 to 0.10266
 Nadroparind− 0.00018− 0.00098 to 0.000620.01117− 0.02974 to 0.052080.00016− 0.00268 to 0.00300
Outpatient expenditure per DDD
 Total low molecular weight heparins0.00517*0.00395 to 0.00639− 0.11977*− 0.17028 to − 0.06926− 0.00786*− 0.01139 to − 0.00433
  1. aThis was the only one that remained as a non-restricted prescription low molecular weight heparin in the formulary after the intervention
  2. bAfter the intervention, this low molecular weight heparin was removed from the formulary
  3. cAfter the intervention, this low molecular weight heparin was restricted to situations where enoxaparin could not be used
  4. dThis low molecular weight heparin had already been removed from the formulary before the intervention
  5. *p < 0.05