Description
Return block and slot coordinates for an indexed subject.
Allocation bookkeeping distinguishes arm counts, indexing and vocabulary matches from generation of a concealed random sequence. Floored targets can leave unassigned remainders, and a local balance score does not establish that an allocation method protects a trial from selection bias.
Return block and slot coordinates for an indexed subject.
When to use this tool
Use Research Randomization Block Slot Index when checking the stated clinical-research record, allocation, timing, analysis or evidence-basis convention.
How to use the tool and how it works
- Enter subjectIndex, blockSize, origin. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read block, slot, firstSubject. Use the output convention below.
Return block and slot coordinates for an indexed subject. Require whole blockSize >= 1, origin zero/one and subjectIndex >= origin; use exact integer division of index-origin for zero-based block/slot and return the block's first subject index.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| subjectIndex | Subject Index | Required. Safe integer. |
| blockSize | Block Size | Required. Safe integer; minimum 1. |
| origin | Origin | Required. Safe integer; minimum 0; maximum 1. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| block | Block | Required. Safe integer. |
| slot | Slot | Required. Safe integer. |
| firstSubject | First Subject | Required. Safe integer. |
{
"input": {
"subjectIndex": 12,
"blockSize": 4,
"origin": 1
},
"output": {
"block": 2,
"slot": 3,
"firstSubject": 9
}
}Limitations and assumptions
- This is indexing only, without generating arm assignments, randomization, concealment or a suitable block size.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use the complete approved protocol, authenticated source records and qualified clinical/statistical oversight for actual trial design, conduct and interpretation.
References
Similar or alternative tools
- Randomization Stratum Index
Look up a serialized factor tuple in supplied strata.
- Allocation Stratum Unfilled Slot Count
Return unfilled slots and overfilled strata.