(Medicare Claims Processing Manual)

3. If adding all of the cases listed on the IRF Arthritis Verification Report for that IRF would be enough to increase the IRFs compliance percentage to equal or exceed 60 percent, then the A/B MAC (A) must use generally accepted statistical sampling  techniques  to obtain a statistically  valid  random  sample  of those  patients listed for the IRF on the IRF Arthritis Verification Report. If the total number of patients listed for the IRF on the IRF Arthritis Verification Report is less than 10, then the A/B MAC ( A) will review all patients listed for the IRF on the IRF Arthritis Verification Report. (Note that if adding all the cases listed in the IRF Arthritis Verification Report for that IRF would not be enough to increase the IRFs compliance percentage to equa l or exceed 60 percent, then the A/B  MAC  (A) will not proceed further with the IRF arthritis verification process and will use the presumptive compliance percentage generated from section C  above.)   4. The A/B MAC (A) will obtain and examine the medical record sections and any other pertinent information submitted by the IRF to determine if the patients  from the random sample obtained in step 2 meet all of the severity and prior treatment requirements specified in  140.1.1B -D.  5. The percentage of patients from the list that the A/B MAC (A) determines to have met the severity and prior treatment requirements specified in 140.1.1B -D will be extrapolated to the complete list of patients for the IRF on the IRF Arthritis Verification  Report.  6. The A/B MAC  (A) shall then add the appropriate  number  of cases  (based  on the percentage in step 4) from the IRF Arthritis Verification Report to the  cases that meet the presumptive compliance criteria, and re -calculate the IRFs presumptive compliance percentage.  For example:   IRF A submitted 545 IRF -PAIs in the compliance review  period.    IRF As presumptive compliance percentage (determined by the A/B  MAC  (A) using the steps outlined in subsection C above) was less than 60 percent.    In this case, the A/B MAC (A) must access the IRF Arthritis Verification Report.   The IRF Arthritis Verification Report shows 100 patients listed for IRF  A.   The A/B MAC (A) determines that inclusion of all 100 patients listed for IRF A would increase IRF As presumptive compliance percentage  enough to meet or exceed the 60 percent  threshold.   The A/B MAC (A) uses generally accepted statistical sampling  techniques to randomly select 10 patients from that list for medical review, and based on the medical review determines that 7 of the 10 patients meet all of the requirements specified in  140.1.1B -D.   The A/B MAC  (A) will then extrapolate this percentage (7/10 = 70 percent) to the full list of patients  shown on the IRF Eligibility  Arthritis  Verification Report for IRF A. Thus, the A/B MAC (A) will add 70 patients (70 percent of 100) listed  for IRF A on the IRF Arthritis  Verification  Report  to the total number  of IRF As patients  that meet  the presumptive  compliance criteria.    The A/B MAC (A) will then recalculate IRF As presumptive compliance percentage with the addition of the 70 cases.    The A/B MAC (A) will base the determination of the IRFs presumptive compliance with the requirements  specified  in 140.1.1B -D on the updated calculation of the IRFs presumptive compliance percentage.    The A/B/ MAC (A) will report this updated presumptive compliance percentage, instead of the presumptive compliance percentage from subsection C above, on the quarterly  report that the A/B  MAC  (A) sends to the appropriate CMS RO (with a copy to the CMS Central Office).   NOTE:  Even when an IRF is presumed to have met the requirements specified above in140.1.1B-D using the updated presumptive methodology calculation, the RO and A/BMAC (A) still have the discretion to use the medical review methodology described in subsection E below to verify the IRFs compliance with the requirements in 140.1.1B- D.  E. - Verification of the Medical Condition Criteria Using the Inpatient  Rehabilitation Facilitys Total Inpatient Population (Medical Review  Methodology)   1. The A/B MAC (A) must use the IRFs total inpatient population to verify that the IRF has met the requirements specified above in 140.1.1B-D if:  (i) the IRFs Medicare population (including Medicare Part A fee -for-service and Medicare Part C (Medicare Advantage) patients, effective October 1, 2009) is not at least 50 percent of its total inpatient population; or  (ii) the A/B MAC (A) is unable to generate a valid IRF compliance review report using the IRF-PAI database methodology specified previously; or (iii) the A/B MAC (A) generates an IRF compliance review report, based on the use of the presumptive methodology, which demonstrates that the IRF has not met the requirements specified above in 140.1.1B- D.  If the IRFs Medicare Part A fee -for-service and Medicare Part C (Medicare Advantage) populations (combined, effective October 1, 2009) comprise less than 50 percent of the IRFs total inpatient population, or the A/B MAC (A) otherwise determines that the Medicare Part A fee- for-service and Medicare Part C (Medicare Advantage) populations (combined, effective October 1, 2009) are not representative of the overall IRF inpatient population, or the A/B MAC (A) is unable to generate a valid report using the pre sumptive methodology, the presumptive determination is that the IRF did not meet the requirements specified above in 140.1.1B -D.  2. As previously stated above, the A/B MAC (A) will instruct the IRF to send the A/B MAC (A) a list showing the hospital patient number of each inpatient that the IRF admitted during the most recent, consecutive, and appropriate 12- month period, as defined by CMS.  The list of hospital patient numbers must include the payer(s) and admission and discharge dates that correspond with the inpatients whose hospital patient numbers are shown on the list. The A/B MAC (A) will then use generally accepted statistical s ampling techniques to obtain a random sample of inpatients  from the list. The random sample of inpatients drawn from the list must be sufficiently large to ensure that the A/B MAC (A) can determine, with at least 95 percent confidence, whether the IRFs compliance percentage is below the required compliance threshold (i.e., not in compliance) or at or above the required compliance threshold (i.e., in compliance).   For example, suppose that the required compliance threshold for an IRF to be in compliance with the requirements specified above in 140.1.1B -D is 60 percent. The A/B MAC (A) reviews a random sample of claims from IRF A and estimates that IRF As complianc e percentage is 58 percent.  Suppose that the standard deviation that the  A/B MAC (A) calculates for IRF As random sample of IRF claims is plus or minus 4 percentage points, so that the 95 percent confidence interval in this particular example is between 54 percent and 62 percent (with 58 percent as the midpoint). In this case, the IRF is considered to be in compliance with the 60 percent rule, since 60 percent is within the 95 percent confidence interval. To verify whether the IRF is in fact in compliance  with the requirements specified above in 140.1.1B -D, the A/B MAC (A) may need to draw a larger random sample of the IRFs inpatients. For example, a larger random sample of IRF As inpatients might have reduced the standard deviation to plus or minus 1 percentage point, which would have led the 95 percent confidence interval to be between 57 percent and 59 percent. This would have demonstrated with 95 percent confidence that the IRF was not in compliance with the requirements specified above in 140.1.1B -D (because the entire 95 percent confidence interval was below the required compliance threshold of 60 percent).   If the compliance percentage threshold differs within the compliance review period (i.e., is 50 percent for a portion of the compliance review period and 60 percent for the other portion of the period), then a random sample of inpatients will be drawn from  each of the two time periods separately.  The use of generally recognized statistical sampling principles may result in a determination that it would be inappropriate to use a sample to determine the facilitys compliance percentage. If a random sample is not appropriate in a particular case, then the A/B MAC (A) will use the IRFs entire inpatient population to determine the  IRFs compliance percentage. In addition, if the IRF had 100 or fewer inpatients during the compliance review period, then the A/B MAC (A) must use the IRFs total inpatient population (consisting of both Medicare and non - Medicare inpatients) to determin e the IRFs compliance percentage.  Prior to selecting the random sample of inpatients, the A/B MAC (A) must allow the IRF to decide if the IRF wants the sample to contain either the patients who were admitted during the IRFs compliance review period (even if some of those patients were dis charged outside of the compliance review period) or the patients discharged during the IRFs compliance review period (even if some of those patients were admitted outside of the compliance review period).  If the A/B MAC (A) uses a random sample of the IRFs inpatient population (rather than the IRFs total inpatient population) to determine the IRFs compliance percentage, then the A/B MAC (A) must ensure that an adequate sample size is used to determine (w ith at least a 95 percent statistical level of confidence) whether or not the IRF has met the requirements in 140.1.1B -D. In some cases, this will require the A/B MAC (A) to expand the size of the random sample of inpatients selected from a particular IRF . The A/B MAC (A) will instruct the IRF to send it copies of specific sections of the medical records for all of the inpatients to be used in the compliance review. The A/B MAC (A) has the discretion to decide which specific sections of the medical recordsto  obtain, provided that the requested medical record sections contain enough information to allow the A/B MAC (A)s reviewers to determine the medical condition(s) for which each inpatient received treatment in the IRF. In addition to submitting the request ed sections of the medical records, the IRF has the discretion to send the A/B MAC (A) other clinical information regarding these same inpatients.  3. The A/B MAC (A) will examine the medical record sections and any other information submitted by the IRF to determine if the IRF meets the requirements specified above in 140.1.1B -D.  To determine if a specific inpatient matches one of the medical conditions specified in 140.1.1C, the A/B MAC (A) may use the diagnosis and impairment group codes specified in the appropriate files listed in Presumptive Methodology Files  Implementation of Changes that is attached to the IRF Compliance Rule Specification Files, which can be downloaded from the IRF PPS website at http://www.cms.gov/Medicare/Medicare -Fee-for-Service - Payment/InpatientRehabFacPPS/Criteria.html , for general guidance.  The A/B MAC (A) is not permitted to use these codes to make a final determination as to whether or not the specific inpatient required intensive rehabilitation services for treatment of one or more of the medical conditions specified in 140.1.1C. The determination of whether a specific inpatient required intensive rehabilitation services for treatment of a condition can only be determined through careful review of that inpatients unique clinical characteristics and circumstances, as reflected in the inpatients medical record.   4. In general, when the A/B MAC (A) is using a sample of medical records to determine compliance with the requirements in 140.1.1B- D, the A/B MAC (A) always has the discretion to determine if a patient meets or does not meet any of the medical conditions listed  in 140.1.1C based upon a review of the clinical record, regardless of the results of the presumptive methodology described previously. In other words, the compliance percentage that is determined using the medical review methodology described in this section will supersede the compliance percentage that was determined for the same compliance review period using the presumptive methodology. To ensure that the compliance review process is similar for all IRFs, the A/B MAC (A) must have written policies that describe the reasons for using a random sample of medical records to determine an IRFs compliance percentage when the presumptive methodology has shown that the IRF met the compliance  threshold.