HL7 CM1 Clinical Study Phase Master

Clinical study and trial fields from experience.
HL7 field reference CM1 fields from HL7 v2.5.1 Show fields

These are the generated fields for the version selected at the top of the page. The document stays the same, but the reference panel follows that version.

Fields

FieldNameRequiredRepeatableTypeTable
CM1.1 Set ID - CM1 Yes No SI
CM1.2 Study Phase Identifier Yes No CE
CM1.3 Description of Study Phase Yes No ST

CM1 defines a phase within a clinical study, so messages can refer to trial stages consistently.

The standard describes CM1 this way: Each Clinical Study Phase Master (CM1) segment contains the information about one phase of a study identified in the preceding CM0. This is an optional structure to be used if the study has more than one treatment or evaluation phase within it. The identification of study phases that the patient enters are sent in the CSP segment: sequence 2. The CM1 segment describes the phase in general for the receiving system.

Clinical-study segments tie a message back to a trial, phase, schedule, subject registration, and protocol-specific events. They are not general observation notes; they support trial governance and reporting.

The useful data is usually the combination of study identifiers, phase identifiers, schedule timing, and subject status. Keep protocol codes and local study IDs aligned with the system that is managing the trial.

The v2.5.1 structures show CM1 in MFN_M06 - Clinical study with phases and schedules master file and MFR_M06 - Clinical study with phases and schedules master file. That tells you where it can appear, but the implementation guide still decides which optional fields are meaningful.

For practical interface work, read the generated field panel for datatype, required, repeatable, and table details, then use the notes below to decide what the field should mean in the receiving workflow.

CM1-1 Set ID - CM1 RequiredR SingleS TypeSI

CM1-1 is the sequence number for this CM1 segment within its repeating group. It keeps multiple CM1 lines in order; it is not the business identifier for the study workflow.

CM1-2 Study Phase Identifier RequiredR SingleS TypeCE

CM1-2 identifies the Study Phase Identifier for this study workflow. Send the identifier that the receiving system actually keys on, and keep the assigning authority or coding system visible when the datatype supports it.

CM1-3 Description of Study Phase RequiredR SingleS TypeST

CM1-3 is human-readable context. Keep it useful for display and troubleshooting, but do not hide required workflow logic here unless the implementation guide explicitly says the receiver parses it.

Related links