The Most Costly and Common Errors in Scoring the OASIS Assessment

 The Outcome and Assessment Information Set (OASIS) is the backbone of home health care, determining everything from patient care planning to reimbursement and quality ratings. However, because the manual is hundreds of pages long and frequently updated, scoring errors are incredibly common. 

Accuracy isn't just about compliance; it's about ensuring the patient's clinical picture matches the data sent to CMS. Here are the most frequent scoring errors found in OASIS assessments, along with how to avoid them. 

1. M1800-M1860: The "M-Items" (ADLs and IADLs) 

Functional items are arguably the most miscoded section of the OASIS. The most frequent mistake is coding based on what the patient "can" do rather than their actual performance and safety during the assessment. 

• The Error: Coding a patient as "Independent" because they can walk across the room, even though they are at a high risk of falling or require verbal cueing. 

• The Correct Approach: Assessment should be based on the patient’s ability to perform the task safely more than 50% of the time during the look-back period. If a patient needs a "stand-by" person for safety, they are not independent. 

2. M1610: Urinary Incontinence 

This item is frequently underscored because clinicians often focus only on "accidents" rather than assessing preventative measures such as depends. 

• The Error: Marking a patient as "continent" because they wear pull-ups and stay dry. 

• The Correct Approach: If a patient requires a device (pad, diaper, catheter) to manage incontinence or prevent leakage, they are not considered "continent" in the strictest sense of the OASIS definition. 

3. M1311: Pressure Ulcer Staging 

Wound care documentation is a high-scrutiny area for auditors. The primary error involves the "reverse staging" of healing ulcers. 

• The Error: Changing a Stage 4 pressure ulcer to a Stage 3 because it is getting smaller and shallower. 

• The Correct Approach: According to clinical standards, pressure ulcers never reverse stage. A healing Stage 4 ulcer is documented as a "healing Stage 4," not a Stage 3. Additionally, clinicians often fail to identify "Unstageable" wounds correctly, particularly when eschar or slough obscures the wound bed. 

4. M2001: Drug Regimen Review 

This item identifies whether the agency conducted a drug regimen review and contacted a physician regarding "clinically significant issues." 

• The Error: Marking "No issues found" when there is a clear medication discrepancy (e.g., the patient is taking two different brands of the same generic medication). 

• The Correct Approach: Any potential adverse effect, drug interaction, or duplicate therapy must be flagged. If an issue is found, the clinician must document that the physician was contacted and a response was received by midnight of the next calendar day to score this correctly. 

5. M1033: Risk for Hospitalization 

This section is often completed hastily, leading to missed points that reflect the patient’s true acuity. 

• The Error: Overlooking "soft" risk factors like polypharmacy (taking 5 or more medications) or prior emergency room visits in the last six months. 

• The Correct Approach: A thorough review of the patient’s recent medical history and a "brown bag" medication review are essential. Failing to check all applicable boxes can result in an inaccurate risk profile, which has an impact on the agency’s value-based purchasing scores.

Key Tips for Accuracy 

Assess, Don’t Assume: Never take a patient’s word at face value. If they say they can shower alone, ask them to demonstrate the movements required to get into the tub. 

Consistency is King: Ensure that the OASIS scores match the clinical narrative notes. If the OASIS scores the patient as independent in transfers, but the physical therapy note says they need "minimal assistance," it creates a red flag for auditors. The

By focusing on these high-error areas, home health agencies can improve their data integrity, secure appropriate reimbursement, and, most importantly, provide a more accurate plan of care for their patients 

If you are not sure of the accuracy of the OASIS assessment scoring and are concerned that it may lead to penalties down the road, contact Kenyon HomeCare Consulting at 206-721-5091 or email gkenyon@kenyonhcc.com. We will provide 5 free reviews of OASIS assessment scores and provide a report of the findings. We have expert trainers in OASIS assessment.