How to avoid coding pitfalls for ambulatory services billing

Ambulatory services documentation offers compliance challenges as complex as inpatient services documentation that providers need to be aware of to avoid potential compliance risks while documenting for billing. Ellis Knight, M.D., Senior Vice President/Chief Medical Officer, of the Coker Group, focused on ambulatory coding in an HCCA webinar titled “Clinical Documentation for Compliant Coding—It’s No Longer Just an Inpatient Issue.”

Clinical documentation improvement

Knight noted that coders “speak” a different language than clinicians and therefore clinical documentation improvement (CDI) has been mainly a translational process. Specifically in relation to medical diagnoses, translating what a clinician may write down in the clinical note versus how the coder interprets the clinical note for billing purposes. Historically the focus has been on inpatient documentation, especially documentation to justify diagnostic related group (DRG) assignment and capture of major complications and co-morbidities (MCCs) and complications and co-morbidities (CCs). As a result, the “problem” is that reimbursement occurs with parties arriving at the same diagnosis with different billing codes.

Ambulatory documentation

As such, ambulatory documentation is equally as complex as the inpatient documentation arena, involving thousands of codes. A major complicating factor is that time-frame and volume of patient encounters makes ambulatory CDI a much different work process than inpatient CDI. Knight noted that among the many compliance risks associated with ambulatory CDI, documentation must support: (1) medical necessity of services rendered (CPT codes); (2) specific services and level of care provided to the patient (CPT and HCPCS codes); (3) diagnoses (ICD-10); (4) severity of illness and clinical complexity (HCCs); and (5) quality of care rendered (HEDIS).

For medical necessity, the clinical documentation must justify the ordering of tests, performance of procedures, referrals to specialists or consultants, prescribing of medications and other activities which payers must cover. It must document services and level of services performed, as errors leave practitioners at risk for overbilling the carrier which could result in treble damages under the False Claims Act. Moreover, Knight stressed that it is not enough to just document. HCCs must be documented on an annual basis and addressed, i.e., monitored, evaluated, assessed or treated, in order to be captured. In regards to quality of care, the clinical documentation must include provision of certain quality of care measures, e.g., immunizations, tobacco use, smoking cessation counseling, BMI measurement, obesity counseling, preventive care (colonoscopy, mammography).

Fighting home health and ambulance fraud by putting providers on a map

CMS released public data sets and a mapping tool regarding the availability and use of Medicare services provided by ground ambulance suppliers and home health agencies. The data release is intended to improve care delivery through transparency and information sharing. CMS is using the data to identify areas where services are saturated and where there are high risks of fraud and abuse.


On February 2, 2016, CMS announced a six-month extension of the temporary enrollment moratoria on new ground ambulance suppliers and home health agencies sub-units and branch locations in Medicare, Medicaid, and the Children’s Health Insurance Programs (CHIP) in seven geographic areas (see Some new providers still unable to enroll in high-risk fraud areas, Health Law Daily, February 1, 2016). Together with the data and mapping tool, CMS believes it can use the moratoria to fight fraud and safeguard the federal healthcare programs.


Home health providers see the data release as a signal from CMS that it plans to step up its home health fraud fighting efforts. Along with the data release, CMS announced plans to use the data to pinpoint high-risk providers for increased site visits. CMS also plans to engage in monthly monitoring of home health enrollment data in order to identify and deactivate providers that do not meet Medicare requirements.

Data tools

The Moratoria Provider Services and Utilization Data Tool includes interactive maps and a dataset to identify geographic areas that might undergo consideration for a new moratorium on provider and supplier enrollments. The data includes the number of providers in a given geographic area and identifies the number of beneficiaries that use a specific health service in a particular region. The interactive maps allow for comparisons between these regions. The tool was developed from ground ambulance and home health agency paid claims data covering October 1, 2014 through September 30, 2015. The data will be updated quarterly.