The clinical investigation report (CIR) is the final scientific and regulatory document that closes a clinical investigation of a medical device under MDR. It is required by MDR Article 77 of Regulation (EU) 2017/745, its content is specified by Annex XV Chapter III, and it is written and signed under the Good Clinical Practice standard EN ISO 14155:2020+A11:2024. Article 77 sets the sponsor's obligation to submit the report to the member states in which the investigation was conducted within defined timeframes after the end, temporary halt, or early termination of the investigation, together with a summary presented in terms easily understandable to the intended user. The report must cover the full investigation — the design as run, the subjects as enrolled, the results as measured, the adverse events as recorded, and the conclusions the data actually support — whether those conclusions are favourable, unfavourable, or inconclusive.

By Tibor Zechmeister and Felix Lenhard. Last updated 10 April 2026.

TL;DR

  • MDR Article 77 requires the sponsor to submit a clinical investigation report to the member states in which the investigation was conducted, within defined timeframes after the end, temporary halt, or early termination of the study.
  • The content of the clinical investigation report is specified by Annex XV Chapter III of Regulation (EU) 2017/745 and is enforced section by section by competent authorities and the Notified Body at conformity assessment.
  • The report must be accompanied by a summary presented in terms that are easily understandable to the intended user.
  • The report is written under EN ISO 14155:2020+A11:2024, which provides the Good Clinical Practice operational framework for authorship, signing, and archival.
  • The report must be honest about unfavourable and inconclusive results. Selective reporting is a compliance failure and a credibility failure at Notified Body review.
  • The report feeds directly into the clinical evaluation report (CER) under MDR Article 61 and Annex XIV and is read against the clinical investigation plan the study was authorised against.

Why the clinical investigation report is the document the regulator reads last and the Notified Body reads first

The clinical investigation report is the closing document of a clinical investigation, but in the life of the technical file it is the opening document of the clinical argument for conformity. The competent authority that authorised the study reads it to confirm that the study was run as planned and that subjects were protected. The ethics committee reads it to close their oversight. And the Notified Body, sometimes years later, reads it as the primary source for every clinical claim in the clinical evaluation report that depends on the investigation.

That dual audience is why the clinical investigation report cannot be written as a marketing summary of favourable findings. It has to be a faithful account of what happened — the design as run, the protocol deviations, the recruitment difficulties, the adverse events, the missing data, the primary endpoint result whether it landed on the predicted side or not, the secondary endpoints, and the limitations the data actually carry. The Notified Body will compare the report back to the clinical investigation plan the study was authorised against. Any silent divergence between the two is a finding. Honest divergence, explained, is not.

This post walks through the legal basis for the clinical investigation report under MDR Article 77, the content specified by Annex XV Chapter III, the publication and submission obligations, the ethics committee side, how the report lands in the clinical evaluation report, and the mistakes that come back most often at review.

The legal anchor — MDR Article 77

MDR Article 77 of Regulation (EU) 2017/745 governs reporting by the sponsor in relation to the end, temporary halt, or early termination of a clinical investigation. The sponsor must notify the member states in which the investigation was conducted that the investigation has ended, and must submit the clinical investigation report together with a summary.

Three elements of Article 77 do the heavy lifting and deserve to be understood precisely.

First, the obligation is on the sponsor. Under MDR Article 72 the sponsor holds the accountability, and Article 77 makes that accountability concrete at the reporting stage. Small sponsors carry the same obligation as large ones. A startup cannot outsource Article 77 invisibly to a contract research organisation — the CRO can draft, the sponsor signs and submits.

Second, the trigger is the end of the investigation, or a temporary halt, or an early termination. All three are reportable. An investigation that is stopped for safety reasons, for futility, or for sponsor logistics still produces a report under Article 77. There is no exemption for studies that did not reach the planned enrolment or that did not produce favourable results. The obligation attaches to the investigation as it actually happened.

Third, the report must be accompanied by a summary that is easily understandable to the intended user. This is not a scientific abstract written for statisticians. It is a lay-accessible summary that a clinician, a patient, or an interested member of the public can read and understand. The intended user language comes from the Regulation itself and the summary is judged against it.

The reporting timeframes in Article 77 are defined and absolute. A sponsor that misses them creates a regulatory finding that follows the investigation into the technical file and into the Notified Body audit. The responsible person on the sponsor side must know the timeframes that apply to their study and have them on a calendar before the study closes.

Required content — walking Annex XV Chapter III

MDR Annex XV Chapter III specifies the content of the clinical investigation report. Every section listed in Chapter III must be present. Missing a section is not a formatting issue — it is a compliance issue, and reviewers will ask for the missing section before they close out their review.

EN ISO 14155:2020+A11:2024 is the harmonised Good Clinical Practice standard, and its own clinical investigation report template maps closely onto Annex XV Chapter III. Use the standard as the operational template. Use Annex XV Chapter III as the legal checklist. Where the two diverge, Annex XV wins.

Identification of the investigation, the sponsor, and the investigators. The same identification carried in the clinical investigation plan, updated to reflect the investigation as actually run. Every investigator at every site. The monitor. The sponsor's authorised representative. The signatures that close the document.

Identification and description of the device. The device under investigation as it was used in the study. Version, configuration, software build where applicable, materials, and any changes across the investigation period. Any discrepancy between the device as described in the clinical investigation plan and the device as used must be explicit and justified.

Design of the investigation as it was actually conducted. The design in the plan, restated. Any deviations from the plan during conduct, described honestly and categorised. The number of subjects enrolled, screened, included in the full analysis set, and included in the per-protocol set. The number of sites that contributed data. The duration of subject follow-up actually achieved.

Results. The primary endpoint analysis. Secondary endpoint analyses. Subgroup analyses if pre-specified. The results presented in the form the statistical analysis plan called for — not in a reinterpreted form that paints a better picture. Missing data handled as the plan said it would be handled. The result as measured, regardless of what the result is.

Safety results. Adverse events recorded during the investigation. Serious adverse events. Device deficiencies. The causality assessments. The reporting to the competent authority and the ethics committee that was done during the study under MDR Article 80. A safety narrative for each serious event where appropriate.

Discussion and overall conclusions. The scientific conclusions the data actually support. The limitations of the study. The generalisability of the findings. The relationship between the results and the clinical claims in the intended purpose. Where the results support the claims, that is stated. Where they do not, that is stated. Where the data are inconclusive, that is stated too.

Summary understandable to the intended user. The lay-accessible summary required by MDR Article 77. Written in language a clinician or patient can read without translation. Not a marketing document. Not a scientific abstract. A plain, honest summary of what the study set out to do, what it found, and what the findings mean.

Signatures and date. The clinical investigation report is signed by the sponsor and, under EN ISO 14155:2020+A11:2024, by the coordinating investigator or the investigator at each site, per the sponsor's signing procedure. Unsigned clinical investigation reports are not final.

Every Annex XV Chapter III section has to earn its place in the report. A report that skips sections or collapses them into a single narrative is a report that will come back from review.

The publication timeline

MDR Article 77 sets defined timeframes for submission of the clinical investigation report to the member states in which the investigation was conducted. The sponsor must know these timeframes before the study closes and must build the internal report-writing timeline so that the submission lands inside them.

There are three triggers for the reporting clock.

End of the investigation as planned. The investigation reaches its last subject, last visit, the data are locked, and the report-writing phase begins. The clock under Article 77 runs from the end of the investigation as defined in the clinical investigation plan.

Temporary halt. The investigation is paused — for safety, for a problem with the device, for a site issue. Article 77 requires notification and, where applicable, reporting within the defined timeframe tied to the halt.

Early termination. The investigation is stopped before completion. The shortest reporting window typically attaches to early termination for safety reasons, because the member states need the information fast to protect any subjects in other ongoing investigations.

The competent authorities of the member states where the investigation ran are the recipients. For multi-state investigations, the submission goes to each state under its national procedure, and the coordinating member state procedures of MDR Chapter VI apply where relevant. National procedures differ in the submission channel; the legal obligation under Article 77 does not.

A sponsor that starts drafting the clinical investigation report only after the database is locked is already behind. The discipline we teach startups is to have the report outline drafted before enrolment closes, the sections that do not depend on final data populated during the study, and the analytical sections ready to drop in the moment the statistical analysis plan executes against the locked database. The Article 77 clock does not wait for a report-writing ramp-up.

Ethics committee submission

Parallel to the Article 77 submission to competent authorities, the sponsor closes out the ethics committee oversight. The ethics committee that approved the investigation in each member state receives notification of the end, temporary halt, or early termination of the investigation and, per national procedure, the clinical investigation report or the summary.

National procedures differ on what the ethics committee receives and when. Some member states require the full report. Others require the summary and make the full report available on request. The sponsor's regulatory plan for the study, built when the clinical investigation plan was written, should include the ethics committee closure procedure for every state in which the investigation runs.

The ethics committee closure is not optional. Every investigation that was opened under ethics committee approval must be closed under ethics committee notification. An investigation left in an "open" state at the ethics committee because the sponsor forgot to close it is a finding waiting to surface — at the next Notified Body audit, at the next inspection, at the point where the sponsor tries to open the next investigation with the same committee.

Integration with the clinical evaluation report

The clinical investigation report does not live in a folder on its own. It feeds directly into the clinical evaluation report (CER) required by MDR Article 61 and Annex XIV. The CER cites the clinical investigation report as the primary source for the clinical data the investigation produced. The data analysis in the CER draws from the report's results section. The conclusions of the CER about safety, performance, and clinical benefit use the report as their evidence base for the claims the investigation was designed to support.

For that integration to work, the clinical investigation report must produce results that are usable in the CER. Results that are vague, selectively reported, or disconnected from the intended purpose cannot be dropped into the CER without re-analysis. Results that answer the pre-specified primary endpoint cleanly, with the pre-specified analysis, can. The discipline of writing the CIP tightly (see Writing a Clinical Investigation Plan (CIP) Under MDR Article 62) pays out at exactly this moment — when the clinical investigation report flows into the CER without rework.

The Notified Body reviewing the CER will read the clinical investigation report against the clinical investigation plan and against the CER's claims. Three-way consistency is what they are looking for. When the three documents agree, the review moves quickly. When they disagree, the review does not move at all until the disagreement is resolved.

Common mistakes in clinical investigation reports

A short list of the failures that come back most often at review.

Selective reporting of favourable endpoints. The primary endpoint landed on the wrong side of the predicted effect, so the report foregrounds a secondary endpoint that did land well. This is a credibility failure and a compliance failure, and Notified Bodies are trained to catch it.

Silent protocol deviations. Deviations from the clinical investigation plan that are not disclosed in the report. Reviewers will find these by comparing the report to the plan and to the monitoring records. Honest disclosure of deviations, with the reasoned assessment of their impact, is always the better path.

Missing or hand-waved summary for the intended user. Sponsors draft the scientific sections carefully and then append a summary that is really just a shortened abstract. The Article 77 summary obligation asks for a lay-accessible document, not a condensed scientific one.

Disconnection between the report and the risk management file. New risks or new severity estimates surfaced during the investigation but not fed back into the risk management file under EN ISO 14971:2019+A11:2021. Reviewers check for the feedback loop.

Missing signatures. A clinical investigation report that is not signed by the sponsor and the relevant investigators per the signing procedure is not final. Submitting an unsigned report is a procedural failure that delays the reporting clock.

Copy-paste of clinical investigation plan language without updating for actual conduct. The report describes the investigation as it was planned, not as it was run. Reviewers see this immediately because the numbers in the results section do not match the design in the narrative.

Inconclusive result reframed as a positive result. The data do not support the claim but the discussion section writes around it. An inconclusive result is a legitimate outcome that the Regulation and the Notified Body can work with. A misrepresented result is not.

The Subtract to Ship angle on the clinical investigation report

The Subtract to Ship framework applies to the clinical investigation report as it applies to every other regulatory document. The test is not length. The test is whether every section of the report earns its place against Annex XV Chapter III and EN ISO 14155:2020+A11:2024, and whether every claim in the report is backed by a line in the data.

A subtracted clinical investigation report is a faithful report. No padding. No speculative discussion. No hedged conclusions that try to mean different things to different readers. The primary endpoint is reported the way the statistical analysis plan said it would be reported. Adverse events are reported completely. Limitations are stated. The summary for the intended user is written in language the intended user can read.

The sponsors we see struggle with clinical investigation reports are the ones who start writing them after the database locks, treat them as marketing artifacts, and try to dress up results that did not land where the sponsor hoped. The sponsors who produce clean reports start the outline during the study, write the methods sections against the clinical investigation plan as the study runs, populate the results sections the day the statistical analysis plan executes, and write the discussion section honestly. The clean report is always the faster one to get past review.

Reality Check — Where do you stand?

  1. Do you know the Article 77 reporting timeframes that apply to your investigation, and are they on a shared calendar with named owners?
  2. Have you drafted the outline of your clinical investigation report before your last subject completes their last visit?
  3. Is your statistical analysis plan specific enough that the results section of the report can be populated the day the database locks?
  4. Have you committed in writing to reporting the primary endpoint as pre-specified, regardless of the direction of the result?
  5. Is there a procedure in place for disclosing protocol deviations honestly in the report, with reasoned assessment of their impact?
  6. Who signs the clinical investigation report on the sponsor side, and who at the investigator side, and is the signing procedure written down?
  7. Has the lay-accessible summary for the intended user been drafted and reviewed by someone outside the scientific team?
  8. Is there a defined handoff from the clinical investigation report into the clinical evaluation report, with named owners on both sides?
  9. Has the ethics committee closure procedure for each member state in which the investigation ran been mapped?
  10. If new risks surfaced during the investigation, is there a clear path for those findings into the risk management file under EN ISO 14971:2019+A11:2021?

Frequently Asked Questions

What is a clinical investigation report under MDR? A clinical investigation report is the final scientific and regulatory document that describes the conduct, results, and conclusions of a clinical investigation of a medical device. It is required by MDR Article 77 of Regulation (EU) 2017/745, its content is specified by Annex XV Chapter III, and it is written under the Good Clinical Practice standard EN ISO 14155:2020+A11:2024.

When must the clinical investigation report be submitted? MDR Article 77 sets defined timeframes after the end, temporary halt, or early termination of the investigation. Early termination for safety reasons typically triggers the shortest reporting window. The sponsor is responsible for knowing and meeting the timeframes that apply to the specific investigation and the specific member states where it was run.

Who must the clinical investigation report be sent to? Under MDR Article 77, the sponsor submits the report to the member states in which the investigation was conducted. Ethics committees receive closure notification and, per national procedure, the report or the summary. The report then feeds the clinical evaluation report that the Notified Body reviews during conformity assessment under MDR Article 61 and Annex XIV.

Does the clinical investigation report have to be published? MDR Article 77 requires submission to the member states together with a summary presented in terms easily understandable to the intended user. Transparency of clinical investigation results is part of the regulatory framework. The sponsor's publication policy, declared in the clinical investigation plan as required by Annex XV Chapter II, governs the sponsor's broader publication commitments.

What if the clinical investigation produced unfavourable or inconclusive results? The report is submitted regardless. Article 77 does not distinguish between favourable and unfavourable outcomes. The report must state the result as measured, with the pre-specified analysis, and discuss what the data actually support. Selective reporting is a compliance failure at competent authority submission and at Notified Body review.

What is the difference between the clinical investigation report and the clinical evaluation report? The clinical investigation report (CIR) closes one specific clinical investigation of a device and is required by MDR Article 77. The clinical evaluation report (CER) is the overall document that compiles all clinical evidence for the device — including data from the clinical investigation report, literature, equivalence, and post-market data — under MDR Article 61 and Annex XIV. The CIR feeds the CER.

Who signs the clinical investigation report? Under EN ISO 14155:2020+A11:2024 and the sponsor's signing procedure, the sponsor signs the report and the coordinating investigator or the investigators at the sites sign per the procedure the sponsor sets in the clinical investigation plan. An unsigned clinical investigation report is not a final report and cannot close the Article 77 obligation.

Sources

  1. Regulation (EU) 2017/745 of the European Parliament and of the Council of 5 April 2017 on medical devices, Article 77 (information from the sponsor in case of temporary halt or early termination of a clinical investigation and in case of the end of a clinical investigation), Annex XV Chapter III (clinical investigation report). Official Journal L 117, 5.5.2017.
  2. EN ISO 14155:2020+A11:2024 — Clinical investigation of medical devices for human subjects — Good clinical practice.

This post sits in the Clinical Evaluation & Clinical Investigations cluster of the Subtract to Ship: MDR blog. Authored by Felix Lenhard and Tibor Zechmeister. If you are closing out a clinical investigation under MDR Article 77 and want a second pair of expert eyes on the report before it goes to the competent authority, Zechmeister Strategic Solutions reviews clinical investigation reports at exactly that moment — after the data are locked and before the submission clock runs out.