Introduction

This concept describes a method used to validate shadow billing claims contained in the Medical Services data and presents the results of this validation. Information for this concept is taken directly from the deliverable, A Comparison of Models of Primary Care Delivery in Winnipeg by Katz et al. (2016).

Shadow billing refers to claims submitted by physicians and nurse practitioners who are paid a salary or who work under contract, as opposed to working on a fee-for-service (FFS) basis where claims must be submitted in order to receive payment. These alternative-funded primary care providers typically work at Community Health clinics, WRHA Primary Care clinics and Teaching clinics located within Winnipeg. See the Models of Primary Care Delivery concept for more information about these types of clinics.

Unlike the payment structure in the FFS model, payment to alternative-funded providers is not dependent on the submission of a claim for a particular visit. As a result, there is some uncertainty as to whether the Medical Services data in the MCHP Data Repository captures the same proportion of patient visits to alternative-funded providers as it does to FFS providers.

Shadow Billing Validation Method

Ensuring that the MCHP Data Repository captures shadow billings at a similar rate to FFS billing claims was important in the research by Katz et al. (2016), because many of the comparisons made are between shadow billing and FFS billing claims data.

In Katz et al. (2016), they attempted to validate shadow billing claims made by alternate-funded primary care providers using prescription drug dispensation data from the Drug Program Information Network (DPIN) data and the physician claims data for ambulatory visits from the Medical Services data. The reasoning behind this is that new medication prescriptions are usually preceded by a primary care provider visit.

To determine whether alternative-funded primary care providers shadow bill for their office visits, they identified new incident prescriptions for specific drugs in the fiscal year 2011/2012 in the DPIN database. They then searched for a corresponding ambulatory visit to the prescribing primary care provider in the Medical Services data in the 30 days prior to the prescription drug dispensation date. They compared the proportion of visits to primary care providers working in alternative-funded clinic models who shadow bill to those working in FFS models who submit medical claims for services provided. Only primary care providers with 100 or more allocated patients were included in this analysis because they are more likely to be full-time providers. Validation occurred if the DPIN data contained a prescription dispensation date within 30 days of the Medical Services claim for an ambulatory visit.

Shadow Billing Validation Results

In Katz et al. (2016), they found corresponding physician claims for ambulatory visits for 92.3% of the prescriptions from alternative-funded primary care providers compared to the 91.7% of the prescriptions from FFS primary care providers. With this result, Katz et al. felt confident that there is no meaningful difference in the submission rate of ambulatory visit billing claims between the alternative-funded and FFS primary care providers included in the study. This finding validated the patient allocation algorithm used in the study and justified the use of the National Algorithm to calculate full-time equivalent (FTE) values for all primary care providers, which was integral to the panel size analysis in the research. See the Primary Care Provider Panel Size concept for information on how the FTE calculations were used to determine primary care panel size.

These validation results were expected for two reasons. First, all of the alternative-funded clinics in Winnipeg included in the study have dedicated staff whose responsibility includes ensuring that shadow billings are submitted. This was not the case for many of the primary care providers included in previous research (see the Cautions section below for a more detailed explanation). Second, the introduction of electronic medical record (EMR) has resulted in automated processes that assist and remind staff at alternative-funded clinics to submit shadow billing claims for patient visits.

Cautions

This validation process was completed using only data for clinics within Winnipeg. Previous research (see Katz et al. (2010) and Katz et al. (2014)) from MCHP suggested that up to one third of all visits for alternative-funded primary care providers may not have medical claims (shadow billings) in the Medical Services data in the MCHP Data Repository. This was based on an analysis of the presence of billing in the Repository associated with a new drug dispensation from a pharmacy where the generation of a new prescription for that drug was thought to be very unlikely without a face-to-face visit with the prescriber. Those analyses included rural alternative-funded primary care providers working as single providers with little administrative support. The 2016 study found that there was no difference in the rate of billing submission between alternative-funded and FFS primary care providers at clinics within Winnipeg.