Modifier Description   Effective
A1Dressing for one wound Jul 01, 2002
A2Dressing for two woundsJul 01, 2002
A3Dressing for three woundsJul 01, 2002
A4Dressing for four woundsJul 01, 2002
A5Dressing for five woundsJul 01, 2002
A6Dressing for six woundsJul 01, 2002
A7Dressing for seven woundsJul 01, 2002
A8Dressing for eight woundsJul 01, 2002
A9Dressing for nine or more woundsJul 01, 2002
AAAnesthesia services performed personally by anesthesiologistJan 01, 2001
ADMedical supervision by a physician: more than four concurrent anesthesia proceduresJan 01, 2001
AERegistered dieticianJan 01, 2005
AFSpecialty physicianJan 01, 2005
AGPrimary physicianJan 01, 2005
AHClinical psychologistJan 01, 1997
AIPrincipal physician of recordJan 01, 2010
AJClinical social workerJan 01, 1997
AKNon participating physicianJan 01, 2005
AMPhysician, team member serviceJan 01, 1997
AOAlternate payment method declined by provider of serviceOct 01, 2013
APDetermination of refractive state was not performed in the course of diagnostic ophthalmological examinationJan 01, 1997
AQPhysician providing a service in an unlisted health professional shortage area (hpsa)Jan 01, 2006
ARPhysician provider services in a physician scarcity areaJan 01, 2005
ASPhysician assistant, nurse practitioner, or clinical nurse specialist services for assistant at surgeryJan 01, 1999
ATAcute treatment (this modifier should be used when reporting service 98940, 98941, 98942)Jan 01, 1998