This is the Continuous Integration Build of FHIR (will be incorrect/inconsistent at times).
See the Directory of published versions 
| Task |
Request, Event |
| identifier |
Request.identifier, Event.identifier |
| basedOn |
Request.basedOn, Event.basedOn |
| groupIdentifier |
Request.groupIdentifier |
| partOf |
Event.partOf |
| status |
Request.status, Event.status |
| statusReason |
Request.statusReason, Event.statusReason |
| intent |
Request.intent |
| priority |
Request.priority |
| doNotPerform |
Request.doNotPerform, Event.doNotPerform |
| code |
Request.code, Event.code |
| focus |
Request.product, Event.product |
| for |
Request.subject, Event.subject |
| encounter |
Request.encounter, Event.encounter |
| requestedPeriod |
Request.occurrence[x] |
| executionPeriod |
Event.occurrence[x] |
| authoredOn |
Request.authoredOn, Event.recorded |
| requester |
Request.requester |
| requestedPerformer |
Event.performer.function, Request.performerType |
| owner |
Event.performer.actor, Request.performer |
| location |
Event.location |
| reason |
Event.reason, Request.reason |
| insurance |
Request.insurance |
| note |
Request.note, Event.note |
| relevantHistory |
Request.relevantHistory |
| value[x] |
Request.supportingInfo |
| Task |
ControlAct[moodCode=INT] |
| identifier |
.id |
| basedOn |
.outboundRelationship[typeCode=FLFS].target[moodCode=INT] |
| groupIdentifier |
.inboundRelationship[typeCode=COMP].source[moodCode=INT].id |
| partOf |
.inboundRelationship[typeCode=COMP].source[moodCode=INT] |
| status |
.statusCode |
| statusReason |
.inboundRelationship[typeCode=SUBJ].source[classCode=CACT, moodCode=EVN, code="status change"].reasonCode |
| businessStatus |
.inboundRelationship[typeCode=SUBJ].source[classCode=OBS, moodCode=EVN, code="business status"] |
| intent |
.moodCode |
| priority |
.priorityCode |
| doNotPerform |
.code |
| code |
.code |
| description |
.text |
| focus |
.outboundRelationship[typeCode=SUBJ].target |
| for |
.participation[typeCode=RCT].role |
| encounter |
.inboundRelationship[typeCode=COMP].source[classCode=PCPR, moodCode=EVN] |
| requestedPeriod |
.effectiveTime |
| executionPeriod |
.effectiveTime |
| authoredOn |
.participation[typeCode=AUT].time |
| lastModified |
.inboundRelationship[typeCode=SUBJ, ].source[classCode=CACT, moodCode=EVN].effectiveTime |
| requester |
.participation[typeCode=AUT].role |
| requestedPerformer |
.participation[typeCode=PRF].role.code |
| owner |
.participation[typeCode=PRF].role |
| location |
.participation[typeCode=LOC].role |
| reason |
.reasonCode |
| insurance |
.outboundRelationship[typeCode=COVBY].target |
| note |
.inboundRelationship[typeCode=SUBJ, ].source[classCode=OBS, moodCode=EVN, code="annotation"].value(string) |
| relevantHistory |
.inboundRelationship(typeCode=SUBJ].source[classCode=CACT, moodCode=EVN] |
| restriction |
Instead of pointing to request, would point to component of request, having these characteristics |
| repetitions |
.repeatNumber |
| period |
.effectiveTime(IVL<TS>) |
| recipient |
.participation[typeCode=SBJ].role |
| input |
??? |
| type |
??? |
| value[x] |
??? |
| output |
??? |
| type |
??? |
| value[x] |
??? |