Someone's wrong. And if it's your MDS, you're leaving money on the table every single quarter.
Under the Patient-Driven Payment Model, Section GG — Functional Abilities and Goals — directly drives the PT and OT payment components of your per diem rate. That means a single undercoded transfer item, a rushed mobility assessment, or a bath observation that never actually happened can reduce your Medicare reimbursement by $30 to $80 per day. For a 30-day stay, that's $900 to $2,400. For a facility with 20 active Medicare patients, that error multiplies fast.
CMS data from MAC post-payment reviews consistently shows Section GG as one of the most common sources of reimbursement error in skilled nursing. Most of the mistakes aren't deliberate — they're process failures. Coordinators coding from memory instead of observation notes. Therapy documenting GG separately from nursing. Admission assessments completed after the correct window. Each mistake is fixable. But first you have to know which ones you're making.
Why Section GG Is PDPM's Most Financially Critical Section
Before diving into the mistakes, it's worth understanding exactly what's at stake. Under PDPM, Section GG scores feed directly into two of the five payment components:
- Physical Therapy (PT) component — driven by the GG Self-Care and Mobility scores at admission
- Occupational Therapy (OT) component — also driven by GG Self-Care and Mobility at admission
The GG score determines which "clinical category" a patient falls into for PT and OT, and each clinical category carries a different base per diem rate. A patient coded as needing more assistance (lower GG score) typically falls into a higher PT/OT clinical category, reflecting greater therapy need. A patient coded as needing minimal assistance (higher GG score) falls into a lower category.
That sounds straightforward — but the error pattern goes in both directions. Undercoding GG (making the patient appear more independent than they are) reduces your reimbursement rate. Overcoding GG (making the patient appear more dependent than they are) creates audit exposure. Neither is where you want to be.
- PT per diem rate — GG mobility score at admission determines PT clinical category
- OT per diem rate — GG self-care score at admission determines OT clinical category
- Discharge goal requirement — each GG item requires a discharge goal to be set
- Quality measures — GG-based functional improvement quality measures affect star ratings
- MAC audit targeting — facilities with GG patterns inconsistent with nursing documentation are high-priority audit targets
The bottom line: getting Section GG right isn't a compliance checkbox. It's a revenue accuracy issue. Facilities that code it correctly capture the reimbursement their patient population deserves. Facilities that code it sloppily lose money quietly — and occasionally get audited loudly.
The 5 Section GG Coding Mistakes That Cost SNFs the Most Money
These aren't edge cases. They're the patterns that appear repeatedly in internal quality reviews, MAC audit findings, and MDS coordinator training sessions across the country.
Coding from Assumption Instead of Direct Observation
This is the most common Section GG error, and the most expensive. An MDS coordinator asks nursing staff what assistance a resident needed during the look-back period. Staff give their best recollection. The coordinator codes based on that — not based on what was documented in real time during actual care delivery.
The problem: human memory underestimates the amount of assistance provided. Staff who work with a resident every day naturally adapt to their needs. They stop noticing how much help they're giving. When asked to recall, they think "she's pretty independent" — but their documentation, if you look carefully, shows two-person assists for transfers three times a week.
Section GG requires coding based on actual observed performance during the 3-day admission assessment window (or 7-day look-back for ongoing assessments). If that observation wasn't documented in the medical record, you don't have it — you have a guess.
Require that Section GG items be coded from concurrent documentation created during the assessment window — not retrospective recall. Build a GG observation form that nursing completes at the time of assistance. Coordinate with therapy to ensure PT/OT observations are documented in a format accessible to the MDS coordinator.
Missing the 3-Day Admission Assessment Window
For PPS assessments, CMS requires that Section GG at admission reflect the patient's functional status during the first three days of the Medicare stay. The window is narrow — Days 1, 2, and 3. If the GG assessment is completed on Day 4 or 5 using retrospective information from Days 1–3, that's a documentation problem. If it's completed using Day 4 or 5 observations (because "they're more representative"), that's a coding error.
Many facilities have a workflow where the MDS coordinator completes Section GG after receiving therapy evaluations — which often aren't done until Day 3 or 4. By the time the GG coding happens, the look-back window has technically closed. Coordinators fill it in as best they can, but the contemporaneous documentation to support it often doesn't exist.
Establish a workflow where GG observation documentation begins on Day 1 of admission. Therapy and nursing should know that GG coding begins immediately. Create a standing protocol that PT/OT evaluations include GG-specific language from Day 1, even if the full evaluation isn't complete until Day 3.
Nursing and Therapy Coding GG Independently — With Different Numbers
Section GG is designed to be an interdisciplinary assessment. Nursing observes self-care and mobility during ADL routines. Therapy observes functional performance during treatment sessions. Ideally, both sets of observations inform a single, consistent GG score.
In practice, many facilities have therapy complete their own GG documentation in the therapy record and nursing complete separate ADL documentation — and the MDS coordinator codes GG from one source without reconciling it with the other. The result is a GG score that may not reflect the full clinical picture, and nursing notes that sometimes directly contradict the MDS coding.
That contradiction — nursing documenting two-person assist for transfers while the MDS shows supervision only — is exactly what MAC auditors flag. It doesn't look like a process failure. It looks like miscoding.
Build an interdisciplinary GG reconciliation step into every admission assessment. The MDS coordinator should compare nursing ADL documentation with therapy evaluation notes before finalizing GG coding. Discrepancies should be resolved with both disciplines before the assessment is locked.
Coding "Best Ability" Instead of "Actual Performance"
This one is subtle and frequently misunderstood. CMS guidance for Section GG specifies that items should reflect the patient's usual performance — meaning what actually happened during the assessment period, not what the patient is theoretically capable of on their best day.
Therapy staff, trained to maximize patient potential, sometimes document what a patient can do with cuing and encouragement. That's appropriate for treatment notes. For Section GG, it produces an inflated independence score — because the patient "can do it" under optimal conditions, but their usual performance with nursing during morning care routinely requires more assistance.
The PDPM rate is based on actual assistance need. Coding best ability instead of usual performance systematically undercodes GG — and systematically undercharges for the care you're actually providing.
Clarify coding expectations across disciplines: GG reflects usual performance, not best effort. Provide a brief training session specifically on this distinction — it's counterintuitive for therapy staff and requires explicit instruction. Document what actually happened during each interaction, not the patient's theoretical ceiling.
Not Setting Discharge Goals for Every Applicable GG Item
Section GG includes a discharge goal column that many facilities treat as an afterthought. CMS requires that a discharge goal be set for every GG item that is coded at admission — meaning for every functional activity the patient engaged in during the assessment window. Leaving discharge goals blank or marking them "not applicable" when the admission item was coded is a coding error.
Beyond the compliance issue, missing discharge goals affect GG-based quality measures. The "Percent of Residents Who Made Improvements in Function" quality measure compares admission GG scores to discharge GG scores. If discharge goals aren't set, the data chain breaks — and your quality measure performance may not accurately reflect the functional gains your therapy team is actually achieving.
Build a discharge goal completion check into the MDS review process. Every GG item coded at admission should have a corresponding discharge goal. Make this a hard rule in your pre-submission checklist — an admission GG item with no discharge goal is an incomplete assessment.
Ready-Made GG Coding Tools — Not Templates to Build From Scratch
The FacilityKit MDS Bundle includes Section GG observation guides, interdisciplinary documentation forms, admission assessment checklists, and PDPM coding references. Built for busy coordinators who don't have time to create these themselves.
Reimbursement Impact: What These Mistakes Actually Cost
Abstract errors become concrete when you attach numbers. The following estimates are based on PDPM rate differentials across clinical categories and typical SNF case mix — not exact figures, since PDPM rates vary by facility, year, and patient condition. But the order of magnitude is consistent with what internal QA reviews and MAC audit findings have documented.
| GG Coding Error | Likely Impact Per Resident Per Stay | Annualized Risk (20 Medicare Pts) |
|---|---|---|
| Undercoded GG mobility by 1 assistance level | $15–$40/day × 30 days = $450–$1,200 | $9,000–$24,000 |
| Undercoded GG self-care by 1 assistance level | $10–$30/day × 30 days = $300–$900 | $6,000–$18,000 |
| Nursing & therapy GG scores inconsistent (audit risk) | Extrapolation repayment + legal review costs | $50,000–$200,000+ if audited |
| Missing discharge goals affecting QM scores | Star rating impact → reduced referrals | Varies significantly by market |
| Best-ability vs. usual-performance overcoding | Audit repayment demand | Depends on scope of error pattern |
The range between facilities is wide. A single-facility internal audit conducted by a large regional SNF operator found that correcting systematic Section GG undercoding (primarily Mistake #1 and #4 above) recovered an average of $23,000 per quarter in additional Medicare reimbursement — money that was being left on the table because the clinical care being provided wasn't being accurately reflected in the MDS.
- GG scores at admission inconsistent with ADL documentation in nursing notes
- Therapy documentation showing "supervision only" while nursing notes show physical assist
- Discharge goals left blank or marked N/A when admission items were coded
- GG scores completed after the 3-day assessment window without supporting documentation
- Consistently high PT/OT PDPM rates compared to peer facilities with similar diagnoses
The 4-Step System for GG Accuracy
Fixing Section GG errors isn't a one-time audit — it's a process redesign. These four steps, implemented together, address the root causes of all five mistakes above.
Create a GG Observation Form Used by Both Nursing and Therapy
Design a single observation documentation template — used by nursing during morning care and therapy during treatment sessions — that captures the assistance level provided for each GG item in real time. The MDS coordinator uses this form, not recall or separate documentation systems, to code Section GG. Discrepancies between nursing and therapy observations get flagged and resolved before coding is finalized.
Start GG Documentation on Admission Day 1 — Not Day 3 or 4
Brief nursing staff on every new Medicare admission: GG documentation begins today. Nursing records assistance levels for ADL tasks from the first shift. PT/OT initiate their GG observations from Day 1 of evaluation. By Day 3, you have three days of concurrent documentation to support the assessment — not a retrospective guess.
Build a GG Reconciliation Step Before Assessment Submission
Before any admission MDS is locked, the MDS coordinator reviews nursing ADL notes against therapy evaluation notes for GG-specific items. Any discrepancy (e.g., nursing documents max assist for ambulation; therapy documents supervised ambulation) is resolved in an IDT discussion — not unilaterally by the coordinator. The reconciliation is documented in the IDT meeting notes.
Run a Quarterly GG Accuracy Review Against Locked Assessments
Pull 5–10 locked assessments per quarter and compare GG coding to the underlying documentation. You're not correcting the locked assessments — you're identifying patterns. If you consistently see that nursing documentation supports higher assistance levels than what was coded, you have a systemic undercoding issue to address in training. If therapy documentation shows lower levels than coded, you have overcoding exposure to fix before an audit finds it first.
The Training Gap Most Facilities Miss
Most MDS training programs cover what Section GG items to complete and how to score them. They cover the look-back window, the admission assessment timing, the discharge goal requirement. What they almost never address: the coordination problem between nursing and therapy that causes the majority of GG errors.
Nursing staff think of GG as an MDS thing — the coordinator's job, not theirs. They document ADLs the way they've always documented ADLs, without thinking about whether that documentation is in a format the MDS coordinator can use for GG. Therapy staff think of GG as a therapy thing — their evaluation already includes functional status, so that covers it. Neither group is wrong, exactly. But neither group is building the documentation the MDS coordinator needs.
What Effective GG Training Covers
- For nursing staff: What GG items are, which ADL tasks they map to, and why how you document assistance levels matters for reimbursement. A 20-minute in-service with real examples of "what we need in your documentation" is more effective than any policy binder.
- For therapy staff: The difference between "best ability" coding (appropriate for treatment) and "usual performance" coding (required for GG). How to document GG observations in language that aligns with MDS coding requirements, not just therapy outcome frameworks.
- For the MDS coordinator: How to reconcile discrepancies between nursing and therapy GG documentation, how to document that reconciliation, and how to push back on departments when their documentation is insufficient to support assessment coding.
The single best investment most facilities can make in GG accuracy costs almost nothing: a 30-minute joint training session with nursing charge staff and therapy leads, focused specifically on Section GG documentation requirements. Do it at each new care team orientation and annually as a refresher. The process changes that follow will pay for themselves in the first billing cycle.
MDS Tools That Make Section GG Accuracy Easier
Knowing what to fix is the first step. Having the tools to fix it is what makes the fix sustainable. A few things make the biggest operational difference:
A Joint GG Observation Form
A single, shared form — not nursing's ADL flow sheet and therapy's evaluation format — designed specifically around the GG items the MDS coordinator needs to code. Both disciplines document on the same form during the assessment window. The MDS coordinator pulls one document instead of reconciling two different systems. This alone eliminates most of the inconsistency errors (Mistake #3 above).
A Section GG Coding Reference
A laminated or printed quick reference that maps each GG item to its coding options, the definition of each assistance level, and examples of what each level looks like in practice. Designed for nursing charge staff and therapy assistants who need to document in the moment, not for MDS coordinators who already know the codes. The goal is to get the right words in nursing and therapy documentation — not just in the MDS.
A Pre-Submission GG Checklist
A structured checklist the MDS coordinator runs through before locking any admission assessment. Verifies that each GG item has concurrent documentation to support the code, that discharge goals are set for all coded items, that nursing and therapy documentation is consistent, and that the timing of the observation falls within the assessment window. Three minutes of structured review before submission prevents weeks of documentation work if an audit arrives.
All Three Tools — Pre-Built and Ready to Use
The FacilityKit MDS Bundle includes a GG observation form, coding reference guide, pre-submission checklist, and 15 additional MDS documentation tools. Immediate download, no subscription required.