Reconciling the MPI After a Health System Merger
Two hospitals complete a merger. Hospital A uses a legacy MPI with 214,000 records keyed on a 10-digit medical record number; Hospital B has 168,000 records keyed on a 7-digit number that overlaps numerically with A's sequence. During the first 90 days, the integration team loads both MPIs into a single enterprise index without crosswalk logic. Registration staff begin searching by name and date of birth only. Within six weeks, the data quality analyst reports 1,340 potential duplicate pairs, 210 of which have overlapping inpatient encounters on the same dates. The compliance officer notes that 38 of these overlapping pairs involve patients with different insurance carriers billed for the same service dates. The CIO wants a remediation plan before the next board meeting in 30 days.
1. Identify the governance failure that allowed this situation and describe the minimum data governance controls that should have been in place before the MPI load.
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The failure is a governance failure, not a technical one. Loading two source systems into a single index without a defined survivorship and crosswalk standard meant no authoritative source was designated for identity attributes.
Controls that should have preceded the load:
- Data ownership assignment - a named steward accountable for enterprise patient identity, with authority to approve matching rules.
- Defined match and merge criteria - deterministic rules (exact MRN crosswalk, SSN where available, full name plus DOB plus address) and probabilistic thresholds with documented review requirements before any merge.
- Crosswalk or enterprise identifier - each legacy MRN mapped to a new enterprise ID, preserving source-system traceability rather than overwriting.
- Change control and testing - a pre-load validation sample with a measured false-match rate and sign-off.
- Data quality monitoring - duplicate-rate thresholds with escalation.
Without these, staff defaulted to name/DOB search, which is the weakest possible matching method and the direct cause of the 1,340 candidate pairs.
2. The 38 overlapping pairs with different carriers billed for the same dates represent potential fraud, waste, or abuse exposure. Outline the sequence of actions the HIM leader should take in the next 30 days, distinguishing what must happen immediately from what can follow.
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Immediate (days 1–7):
- Freeze further merges and suspend automated overlays until each of the 38 pairs is manually adjudicated.
- Pull the full encounter, claim, and remittance history for all 38 pairs; determine for each whether it is a true duplicate identity (one patient, two records) or two distinct patients wrongly linked.
- If any pair shows two claims paid for one patient's single service, notify compliance and legal immediately and preserve records under a litigation hold. Do not adjust or rebill before the review concludes.
Short term (days 8–21):
- Adjudicate and correct the 38 pairs; document each decision with reviewer, date, and rationale.
- Run the remaining 1,130 pairs through a stratified sample to estimate the true duplicate rate and size the full cleanup.
- Implement a hard stop requiring a second identifier before any new record creation, and reinstate crosswalk-based search.
Before the board (days 22–30):
- Present findings: root cause, count of confirmed errors, financial exposure, corrective actions, and a monitored remediation timeline.
- Report to the compliance committee; assess whether a self-disclosure obligation is triggered based on confirmed overpayments.
The distinction matters: identity corrections are an operational fix, but confirmed duplicate payment is a compliance event with its own reporting obligations.
3. Recommend how the organization should measure whether the remediation is working over the following two quarters.
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Measurement should track both the residual error and the process that produces it.
Outcome measures:
- Duplicate rate per 1,000 records, measured monthly against a target (commonly below 1–2%), trending down from the current baseline.
- Overlay/merge reversal rate - the proportion of merges later undone. A high rate signals the matching rules are too aggressive.
- Count of open unresolved candidate pairs and average days to resolution.
Process measures:
- Percentage of registrations passing a second-identifier check.
- Percentage of new records created after a documented search rather than a bypass.
- Staff accuracy audits on a random weekly sample of new registrations.
Financial and compliance measures:
- Number of claims corrected or voided due to identity errors.
- Denial rate attributable to eligibility or identity mismatch.
Report these to the data governance committee quarterly with a named owner for each metric. A metric without an owner and a threshold does not drive action.