Home Health Coding — BCHHC Interview Q&A
OASIS and Episode Management
Q: What are the OASIS assessment types and when is each done?
SOC (Start of Care): within 5 days of first visit — opens the 60-day episode.
REC (Recertification of Care): when HH goals not met in 60 days — extends episode.
ROC (Resumption of Care): within 48 hours (2 calendar days) of patient returning from hospital within an episode.
SCIC (Significant Change in Condition): within 60 days of SOC, acute change, no hospitalisation.
Discharge OASIS: at end of each episode.
Q: Who can fill the OASIS assessment?
Skilled Nurse (SN — RN/LPN), Speech Therapist (ST/SLP), Physical Therapist (PT) — all can complete OASIS independently at any timepoint.
OT (Occupational Therapist) is conditional, not a flat no: OT cannot independently establish Medicare eligibility (can't be the sole qualifying service at SOC), but per a CMS rule change effective January 1, 2022, OT can complete the SOC OASIS once another discipline has already established eligibility, and can independently complete Discharge and Recertification OASIS.
OASIS must be completed at each required assessment point.
Q: What is the PDGM and how does primary diagnosis affect payment?
Patient-Driven Groupings Model — replaced PPS in January 2020. Payment per 30-day period (not 60-day). Five factors: timing (early/late), admission source (community/institutional), clinical grouping (12 groups from primary Dx), functional level (OASIS items), comorbidity adjustment (secondary diagnoses).
Primary diagnosis determines clinical group — wrong primary = wrong clinical group = wrong reimbursement.
ICD-10-CM Coding — Core Rules
Q: What is the difference between NEC and NOS?
NEC = Not Elsewhere Classified: more documentation is given BUT no specific code exists. The condition is more specific than the code. Example: DM due to hyperlipidemia → E11.69, E78.5.
NOS = Not Otherwise Specified: LESS information in documentation; vague or unspecified. Specific codes exist but documentation doesn't support using them. Example: Pneumonia NOS → J18.9.
Memory: NEC = more info, no specific code. NOS = not enough info in the documentation.
Q: Explain Excludes1 vs Excludes2 with examples.
Excludes1 = "NOT coded here" — two conditions CANNOT be coded together at the same encounter (mutually exclusive). Example: J44.9 COPD Excludes1 J42 chronic bronchitis — cannot code both.
Excludes2 = "Not included here" — conditions are separate but CAN coexist; code both when both are present. Example: F02 dementia Excludes2 F01 vascular dementia — code both if patient has both.
Q: How do you code HTN + CHF + CKD stage 3?
Use combination code I13.0 (HTN with CHF and CKD stages 1-4). Never code I10 separately when combination codes exist.
Full sequence: I13.0 + I50.22 (chronic systolic CHF) + N18.3 (CKD stage 3).
If also DM type 2 with CKD and anaemia: add E11.22 + D63.1 + Z79.4 (if on insulin).
Rule: HTN combination code changes based on CKD stage.
BCHHC Advanced Scenarios
Q: Patient had CVA 3 months ago with left hemiplegia and aphasia. How do you code for home health?
Three-month-old CVA = sequela phase. DO NOT code acute CVA (I60-I63).
Code residual deficits from I69.3- series (following cerebral infarction):
These are primary/additional diagnoses. Do NOT add original stroke code — sequela codes imply post-infarction.
If haemorrhagic stroke: use I69.1- or I69.2- series instead.
Q: Surgical wound dehiscence with wound VAC, no infection — codes and 7th character?
Code: T81.31XA (disruption of external operation wound).
7th character A: wound VAC present = active wound care/treatment (not just routine care).
If wound VAC absent: use D (subsequent encounter, routine healing).
Key rule: Active wound treatment (wound VAC, active antibiotics) = A. Routine care without active treatment = D.
Secondary: Z48.89 (aftercare following surgery) or Z47.89 (orthopaedic).
Q: Patient on HH for CHF monitoring, also has T2DM on insulin, CKD stage 3, anaemia of CKD. Full coding?
Primary: I13.0 (HTN + HF + CKD stages 1-4 combination)
Heart failure type: I50.22 (chronic systolic CHF)
DM with CKD: E11.22
CKD stage: N18.3
Anaemia of CKD: D63.1
Insulin use: Z79.4
Do NOT code I10 separately — I13.0 includes HTN.
Do NOT omit N18.3 — needed to specify CKD stage even with I13.0.
Q: What A and B codes are used in home health infection coding?
A codes = bacterial and parasitic infections (Chapter 1).
B codes = viral and other organism infections.
Common home health codes: cellulitis L03.-, UTI N39.0, wound infections T81.4-.
B codes used for organism identification: if localised infection + known causal organism, code 1° infection + 2° B code for organism. Example: B96.89 (other specified bacterial agents) with puerperal sepsis.
Common: B96.89 for organism specification in secondary position.
Wound and Skin Coding
Q: How do you code pressure ulcers vs non-pressure chronic ulcers?
Pressure ulcers (L89.-): caused by sustained pressure on bony prominences. Code by stage (1-4, unstageable) and body site.
Non-pressure chronic ulcers (L97.-): lower limbs — diabetic foot, venous stasis, arterial ulcers. Code by site and severity.
Key: L89 = pressure (positional). L97 = non-pressure (vascular/metabolic).
If DM with foot ulcer: E11.621 (DM + foot ulcer) + L97.- (specific ulcer).
Q: What is homebound status and how must it be documented?
Homebound = leaving home requires considerable effort due to illness/injury.
Documentation must show: specific limitation, distance/effort to leave, what assistance needed.
Brief absences allowed: medical appointments, religious services, adult day care.
Examples of valid homebound: severe COPD with SOB on exertion, severe weakness post-surgery, non-weight-bearing on lower extremity, cognitive impairment requiring supervision.
Q: What are the 12 PDGM clinical groups?
Musculoskeletal Rehab, Neuro/Stroke Rehab, Wound Care, Complex Medical/Surgical, Respiratory, Endocrine, Infectious Disease/Neoplasms/Blood, Cardiac/Circulatory, Medication Management/Teaching/Assessment (MMTA), Behavioural Health, Immobility, GI/GU.
Getting wrong primary Dx → wrong clinical group → wrong reimbursement.