Table 2

Covariates included in the interrupted time-series analysis of the OPEN Stewardship Study

VariablePurposeFormDescription
Number of prescriptionsOutcomeIntegerNumber of antimicrobial prescriptions for given indication
Number of visits for indicationOffsetIntegerNumber of patient visits for given indication
Study siteCovariateBinarySouthern Israel versus Ontario, Canada (baseline)
Practice groupRandom interceptIDRandom intercept for practice group (nested within region)
ProviderRandom interceptIDRandom intercept for provider (nested within practice group)
MonthCovariateCategoricalCalendar month (baseline=January)
Month×study siteInteractionInteractionAllows different value for coefficients for Southern Israel
Physician ageCovariateIntegerPhysician age at t−12
Physician age×study siteInteractionInteractionAllows different value for coefficient for Southern Israel
Physician sexCovariateBinaryFemale versus male (baseline)
Physician sex×study siteInteractionInteractionAllows different value for coefficient for Southern Israel
Physician employment statusCovariateBinaryPart-time versus full-time (baseline)
Physician employment status×study siteInteractionInteractionAllows different value for coefficient for Southern Israel
Percent female patientsCovariateContinuousPercentage of visits by female patients
Percent female patients×study siteInteractionInteractionAllows different value for coefficient for Southern Israel
Percent patients 17 and underCovariateContinuousPercentage of visits by patients 17 and younger
Percent patients 17 and under×study siteInteractionInteractionAllows different value for coefficient for Southern Israel
Percent patients 65 and olderCovariateContinuousPercentage of visits by patients 65 and older
Percent patients 65 and older×study siteInteractionInteractionAllows different value for coefficient for Southern Israel
Post-interventionInterventionBinary1 if provider is in intervention group and intervention has occurred, 0 otherwise; level change of the outcome associated with intervention
Post-intervention×study siteInteractionInteractionAllows different value for level change of the outcome for Southern Israel
TimeTrendIntegerTime since the beginning of the study; slope of the time trend of the outcome
Time×study siteInteractionInteractionAllows different value for slope of the time trend of the outcome for Southern Israel
Time×post-interventionIntervention effectInteractionChange in slope of time trend in the intervention group after intervention is received
Time×post-intervention×study siteInteractionInteractionAllows different value for change in slope of time trend in the intervention group after intervention is received for Southern Israel
  • Excludes variables related to the effect of the COVID-19 pandemic.