✳ PRACTICAL GUIDE

How to investigate a recurring denial

Compare affected and successful cases, verify the requirement and test the proposed correction before concluding what caused the problem.

By DueMD3 min read

A reason code is a starting point for investigation. Define the pattern, compare affected cases with similar successful cases, verify the requirement and test the proposed correction. Keep what you observed separate from the cause you are trying to confirm.

Start with a precise observation

Record the period, unit, denominator, service scope and payer product. Describe what changed without deciding the cause. “More initial denials in this defined group” is an observation; “the payer configured the contract incorrectly” is a hypothesis until supported.

Read group, reason and remark information together. CMS’s remittance explanation separates those roles. Avoid assuming that one code always maps to one fix.

Compare like with like

Within your approved environment, compare affected cases with otherwise similar successful cases. Check the timing of interface changes, contract releases, reference data, authorization processes and administrative data. Do not infer a cause from one shared feature that is present in nearly every case.

A useful internal evidence table has a hypothesis, supporting observation, contradictory observation, missing evidence and the next test. That makes uncertainty operational rather than decorative.

Verify the requirement before changing the process

Find the applicable term or official rule and its effective period. Distinguish a rejected or unprocessable submission from an adjudicated denial before choosing the next route. The Medicare contractor guidance is one example of that distinction, not a universal commercial rule.

Never alter clinical coding or medical documentation solely to produce a favorable payment response. Use qualified reviewers and authorized processes for any coding or clinical question.

Check the correction on a new cohort

Document exactly what changed, then watch a comparable group with sufficient follow-up. Keep repeated failures and unexpected new issues visible. A subsequent improvement is evidence to examine, not automatically a causal proof.

Share only a generalized description in Ask DueMD. Removing a patient name is not a complete de-identification method; HHS guidance explains why multiple identifiers and context can matter.

An investigation after an interface change

Illustrative example.

Example investigation itemObservation or next test
Observed pattern40 of 100 cases affected after an interface update
HypothesisA required administrative field was omitted
Counter-checkCompare equivalent cases through the old interface
Evidence neededOriginal outgoing data and the applicable requirement
Correction testAuthorized test submission with independently verified expected behavior
OutcomeMonitor the next comparable cohort; no automatic causal claim

The 40-case count belongs to the illustrative investigation above.

When an explanation is premature

  • Treating correlation as a proven cause.
  • Ignoring contradictory successful cases.
  • Using a payer name instead of exact product scope.
  • Publishing screenshots or supposedly anonymous claim records.

Turn the finding into a test

  1. Define the observation and cohort.
  2. List competing hypotheses and missing evidence.
  3. Verify the requirement and test a specific correction.
  4. Monitor comparable future cases and retain the evidence.
NEXT STEP

Check the proposed correction

Plan a narrow change and compare the next group using the same measurement definitions.

Plan the follow-up →

Keep reading

The denial review guide

The Denial Cost Calculator can estimate the workload associated with the issue. It does not determine the cause.

Sources

Apply the agreement and records relevant to your review. Examples explain the method; they do not determine a payment obligation.

ASK DUEMD

Need a term or calculation explained?

Read an answer or send a general question about the step you are working on.

Calculator values are not attached. Leave out patient and confidential information.