RTI constructed 15 PAC episode definitions in the analytic file and constructed episodes for both acute hospital-initiated and community entrant episodes using the following definitions:
- 30-day fixed-length episode, and
- 30-day variable-length episode.
The endpoint of a fixed-length episode was defined using two different methods. The first method allowed any claim initiating within a fixed period to be part of the episode definition. For example, using this method, the entirety of a 60-day home health claim initiating 25 days after acute hospital discharge was included in the 30-day fixed-length episode definition. In the second method, we prorated claims so that only PAC days within the fixed period (and the associated dollars) were included in the episode. Using the example of the 60-day home health claim initiating 25 days after acute hospital discharge, under the prorated methodology, only visits occurring during the first 5 days of the home health claim (up to day 30 after acute hospital discharge) were included in the 30-day fixed episode definition. As in earlier work, prorated payments were estimated by dividing the total claim Medicare payment amount by the total number of visits on the claim (or the number of days on institutional claims).
Figure 2 provides a schematic of the fixed- and variable-length episodes examined in this work. Additionally, Figure 3 depicts the difference between allowing a claim initiating in a fixed window to finish an episode versus prorating the episode endpoint. Note that an alternative end point to each of the episode definitions is acute hospitalization (a readmission for acute hospital-initiated episodes or the first acute hospitalization for community entrant episodes). Note also that all episode definitions include the initiating event and that episode end points for each of the definitions are calculated based on the discharge date on the claim for the initiating event. For example, in the case of home health community entrants, where a home health claim is the initiating event and may be followed by a series of home health claims for beneficiaries receiving ongoing care, the episode endpoint is calculated using the discharge date from the first home health claim that initiated the episode.
Figure 2. Fixed-Length versus Variable-Length Episodes
Figure 2 is a schematic of the difference between fixed-length and variable-length episodes. Fixed-length episodes include claims within 30 days of discharge from an initiating event. Variable-length length episodes include claims following discharge from an initiating event prior to a 30 day gap in acute or PAC service use.
Figure 3 is a schematic of the difference between fixed-length episodes including any claim initiating within a fixed period versus fix-length episodes that are prorated. Under a prorated approach, only claim dollars and days associated with service use in the fixed-length period are included in the episode. Under the any claim initiating approach, the entirety of a claim initiating prior to the fixed-length end point is included in the episode.
Physician claims were also examined as part of this analysis though only acute and PAC claims were used to define initiating events and episode endpoints. Physician claims with dates of service falling between the admission date on an initiating event and the last date of episode were identified from the Medicare Carrier claims using physician specialty codes and the dollars associated with these services were included in episode payment analyses.
In summary, episodes were constructed on the following dimensions:
- Episode definition
- 30-day fixed length
- 30-day variable length
- Initiating event
- Acute hospital
- Alternative methods of handling the end of fixed episodes
- Any claim initiating
- Alternative episode end point of an acute hospitalization.
Based on these dimensions, the total number of episodes examined in this work includes the 15 episode definitions shown in Table 2. Using these definitions, RTI examined episode patterns, use of PAC services, and payments for both the acute hospital-initiated and the community entrant episodes.
|Fixed or Variable
|Episode End Point|
|Acute hospitalization||Fixed||Any Claim Starting Within 30 Days After Hospital Discharge|
|Acute hospitalization||Fixed||Any Claim Starting Within 30 Days After Hospital Discharge, Excluding Acute Hospital Readmissions|
|Acute hospitalization||Fixed||30-Day Fixed Period Following Hospital Discharge (prorated)|
|Acute hospitalization||Fixed||30-Day Fixed Period Following Hospital Discharge (prorated), Excluding Acute Hospital Readmissions|
|Acute hospitalization||Variable||30-Day Variable-Length Episode|
|Acute hospitalization||Variable||30-Day Variable-Length Episode Excluding Acute Hospital Readmissions|
|HHA||Fixed||Any Claim Starting Within 30 days After Discharge from Initiating Event|
|HHA||Variable||30-Day Variable-Length Episode|
|HHA||Variable||30-Day Variable-Length Episode Excluding Acute Hospitalizations|
|IRF||Fixed||Any Claim Starting Within 30 days After Discharge from Initiating Event|
|IRF||Variable||30-Day Variable-Length Episode|
|IRF||Variable||30-Day Variable-Length Episode Excluding Acute Hospitalizations|
|LTCH||Fixed||Any Claim Starting Within 30 days After Discharge from Initiating Event|
|LTCH||Variable||30-Day Variable-Length Episode|
|LTCH||Variable||30-Day Variable-Length Episode Excluding Acute Hospitalizations|