An inpatient day is a unit of measure denoting the care received by one patient in one 24-hour period. In other words, the number of inpatient days on the HSA-202 form is the total number of inpatient days for all inpatient admissions receiving a particular service during that report month. See Monthly Inpatient Census.

The Indian Health Service (IHS) has certain conventions that are followed when measuring the inpatient day:

• The "24-hour period' is the period between the census taking on two successive days. When the census taking hour is midnight, this 24-hour period will be the same as the calendar day, that is, from 12:00 A.M. through 11:59 P.M.
• The day of admission is counted as an inpatient day, but the day of discharge is not counted.
• One inpatient day is counted for each inpatient admission involving an admission and discharge during the same day, that is, between two successive census-taking hours.
• The unit of one inpatient day is never divided or reported as a fraction of a day.

The Indian Health Service defines an Outpatient Ambulatory Care Visit (ACV) as follows:

* An encounter between a patient and a health care provider in an organized clinic, medical center or hospital within an IHS or tribal facility where service resulting from the encounter is not part of an inpatient stay. 

* The patient or his/her representative must be physically present at the time of service. 

*A patient's representative may only pick up prescriptions.

* A note must be written in the medical record by a licensed or credentialed provider found to be qualified and approved for privileges by the medical staff and facility administrator.

• A visit to two different clinics (such as ENT and Orthopedics) on the same day count as two ACV.  This applies mainly to facilities with specialists and specialty clinics.
• A visit to two providers within the same IHS clinic on the same day counts as one ACV. For example, if a pediatric patient sees a physician assistant in the pediatric clinic and returns later that day to see a pediatrician, only one of those visits will be counted as official IHS workload.
• Pharmacy, x-ray and laboratory that are secondary to another provider visit are not counted as a second visit, that is, a pediatric visit involving pharmacy, x-ray and laboratory would equal one visit.
• Specialty services provided by a contract provider in an IHS facility will be counted as a physician- provided ACV.
• A dental prescription filled in the pharmacy is a pharmacy visit.

The Indian Health Service defines an Outpatient Primary Care Provider Visit (PCPV) as follows:

* An ambulatory care visit in which the provider is a physician, nurse practitioner, physician assistant, nurse midwife or podiatrist.

Dental visits are reported through another system and are therefore excluded from primary care and outpatient visit totals.

PCPVs are a subset of APC (Ambulatory Patient Care) visit totals.

Workload data processed by NPIRS (National Patient Information Reporting System, the IHS national statistical database) documents outpatient visits by location of encounter or where the patient actually had the visit. This processing change has increased the total visit numbers at village clinics while decreasing the outpatient workload numbers at hospital facilities. Before fiscal year 1998 specialty visits at field clinics were coded to the specialist's hospital, thereby crediting the field visit workload to the hospital. The change in coding to where the visit actually occurred reflects a more accurate picture of the community's entire health care workload.

Outpatient (APV and PCPV) workload totals are documented on Report 1A, Ambulatory Care Visits to Service Location by Provider and Month of Service.  See Statistical Summary of Workload for outpatient totals by service unit.