Full, abbreviated or synoptic CSR: choosing the report type

Three formats, one source guideline

ICH E3 (Step 4, 30 November 1995) sets out the structure of a full integrated clinical study report in 16 sections.¹ The same guideline anticipates that not every study in a development programme needs that level of reporting. Its introduction says that, depending on the regulatory authority's review policy, abbreviated reports using summarised data or with some sections deleted may be acceptable for certain studies, and that if an abbreviated report is submitted it should carry enough detail of design and results for the authority to decide whether a full report is needed.¹

ICH E3 does not define a "synoptic" report. That term comes from regional practice. In the United States, the Food and Drug Administration guidance for industry, Submission of Abbreviated Reports and Synopses in Support of Marketing Applications (1999), states that study information should be submitted as full study reports, abbreviated reports or synopses, and explains which studies fall under each.³ The guidance applies to new drug applications, biologics licence applications and supplements. Other authorities have their own expectations, so the decision table below is a starting position to confirm with the authority that will receive the report.

What each format contains

The sections listed for the abbreviated report are those named in the FDA guidance: 1, 2, 3, 4, 9.1, 9.8, 10.1, 12, 13, 14, 16.1.1, 16.1.2, 16.3.1 and 16.4, using ICH E3 numbering.³ Everything else is omitted or condensed. The pattern is consistent: efficacy is summarised, safety is not.

Decision table by study purpose

The assignments below follow the examples in the FDA guidance and the wording of the ICH E3 introduction.¹³ Read the first column as "the role this study plays in the application".

What an abbreviated report omits, and what it cannot omit

Relative to the full ICH E3 structure, an abbreviated report built to the FDA section list leaves out the following.¹³

• Sections 5 to 8: ethics, investigators and administrative structure, introduction and objectives as separate sections. The essentials are covered in the synopsis and in section 9.1.
• Sections 9.2 to 9.7: discussion of design, selection of population, treatments, efficacy and safety variables, data quality assurance and planned statistical methods. The appended protocol carries this detail.
• Section 10.2: the narrative account of protocol deviations.
• Most of section 11: data sets analysed, baseline characteristics, compliance and the statistical and analytical issues. A concise efficacy summary replaces them, with summary statistics such as means, confidence intervals and p-values.
• Most of section 16: investigator lists, randomisation codes, audit certificates, statistical documentation and the efficacy listings.

What stays is the whole of section 12: extent of exposure, adverse events, deaths, other serious adverse events and other significant adverse events with their narratives, laboratory evaluation, vital signs and safety conclusions. The FDA guidance states that abbreviated reports should contain all the safety information included in a full report.³ In practice the safety tables, listings and narratives take the same effort in either format, so the saving from abbreviation is on the efficacy and methods side only.

What a synopsis is, and is not

A synoptic report under the FDA guidance is a summary of the study with enough data to illustrate the results, accompanied by the protocol and amendments. The guidance points to ICH E3 section 2 as one example of the structure and content.³ Safety information from a study reported this way is not dropped: it is carried into the integrated summary of safety, or appended to the synopsis where an application has no integrated summary.

This is a different document from the synopsis that opens every full report. ICH E3 section 2 asks for a brief synopsis, usually limited to 3 pages, with numerical data.¹ The ICH E3 Questions and Answers (R1) of 2012 add that it should be understandable on its own because it is used as a stand-alone document in a Common Technical Document, and that it should cover the study population, disposition, important protocol deviations and treatment compliance as well as efficacy and safety results.² A synoptic report follows the same logic at slightly greater length and adds the safety package.

Worked example: assigning report types across a small programme

The programme below is illustrative. The product, studies and numbers are invented to show how the table is applied.

The programme has eight studies, so the "fewer than six" rule does not force full reports for all. Had study EV-204-303 been stopped on the recommendation of a data monitoring committee for a safety signal, the same enrolment figure would have led to an abbreviated report with full safety reporting.

Other triggers that fix the format

Two situations outside a marketing application also bear on the choice.

• EU database submission. Under Article 37(4) of Regulation (EU) No 536/2014, where a trial was intended to support a marketing authorisation, the applicant submits the clinical study report to the EU database within 30 days after the authorisation is granted, the procedure is completed or the application is withdrawn. A summary of results and a summary for laypersons are due within one year of the end of the trial whatever the outcome.⁴ The Regulation defines the clinical study report as the report that accompanies the marketing authorisation application, so the format chosen for the application is the format that is submitted.
• Public disclosure. CORE Reference advises authors to write the report once for two uses, regulatory review and later disclosure, so that redaction is limited.⁵ That advice applies equally to abbreviated reports and synopses, where patient-level safety detail makes up a larger share of the document.

For investigator-initiated trials with no marketing application, the choice is usually set by the funder, the ethics committee or the sponsor institution's procedures. ICH E3 itself notes that a less detailed report may be appropriate for some kinds of study, depending on their nature and importance.¹ A proportionate approach is consistent with ICH E6(R3), which asks for records that are fit for purpose.⁶

Inputs to agree before writing

Decision record

One line per study: report type, the basis in ICH E3 or regional guidance, and who approved it. Attach any correspondence with the authority.

Output plan

A table, figure and listing shell matched to the report type, so that efficacy outputs are not programmed in full for an abbreviated report and safety outputs are not cut.

Narrative scope

The list of cases that need a narrative under ICH E3 section 12.3.2. This does not shrink with the report type.

Appendix list

The appendix items the chosen format requires, with an owner for each.

Editverse Medical writes full, abbreviated and synoptic reports from the client's protocol, statistical analysis plan and final outputs; scope and entry tier are on the clinical study report (ICH E3) page, and related documents are listed under clinical study reports.

Frequently asked questions

References

1. International Council for Harmonisation. ICH Harmonised Tripartite Guideline E3: Structure and Content of Clinical Study Reports. Step 4 version, 30 November 1995. ICH guideline (PDF)
2. International Council for Harmonisation. ICH E3 Guideline: Structure and Content of Clinical Study Reports. Questions and Answers (R1). 6 July 2012. ICH Q&A (PDF)
3. US Food and Drug Administration. Guidance for Industry: Submission of Abbreviated Reports and Synopses in Support of Marketing Applications. 1999. FDA guidance page
4. Regulation (EU) No 536/2014 of the European Parliament and of the Council of 16 April 2014 on clinical trials on medicinal products for human use. OJ L 158, 27.5.2014, p. 1. Article 37. EUR-Lex
5. Hamilton S, Bernstein AB, Blakey G, Fagan V, Farrow T, Jordan D, et al. Developing the Clarity and Openness in Reporting: E3-based (CORE) Reference user manual for creation of clinical study reports in the era of clinical trial transparency. Res Integr Peer Rev. 2016;1:4. PMID 29451540 · DOI
6. European Medicines Agency. ICH E6 Good clinical practice: scientific guideline. ICH E6(R3) Principles and Annex 1, Step 4, 6 January 2025. EMA page