Decision guide
A quick reference for the five decision types aha assigns — and how the human-intervention threshold decides what you review.
The five decision types
Every variable in the plan is assigned one of five decision types, describing how the source variable relates to the standard:
| Decision | Definition |
|---|---|
| Matched | Identical to the standard variable. No transformation needed; used as-is. |
| Mapped | Directly corresponds to a standard variable. Full consistency after transformations. |
| Partially Mapped | Same underlying concept but different operationalization. Full alignment not achievable. |
| Calculated | Not present in the source, but derivable from one or more source variables. |
| Not Mapped | Cannot be aligned with any standard variable. Excluded from the harmonized output. |
Human intervention & the threshold
Each plan carries a confidence score. The threshold you set in Strategy & Planning (recommended 60%) decides which variables must be reviewed before the pipeline proceeds:
≥ threshold
Human intervention not needed — accepted as proposed.
< threshold
Human intervention needed — review before proceeding.
Rule of thumb
Raise the threshold when accuracy is critical and you want more eyes on the data; lower it to move faster on clean, well-understood sources.
Choosing a transformation
For Mapped, Partially Mapped, and Calculated decisions, aha proposes a transformation sequence. Let its pick stand when source and target differ only in name or coding; step in when units are ambiguous or a value must be derived. See Transformation types for what each option does.