Minimal Detectable Change
Compare observed change with z×√2×SEM minimal detectable change.
Description
Minimal detectable change compares observed magnitude with a measurement-error threshold.
Minimal detectable change compares observed magnitude with a measurement-error threshold. The square-root-two term represents the two-measurement convention used here.1
Compare observed change with z×√2×SEM minimal detectable change.
When to use Minimal Detectable Change
Use this tool to compare observed change with z×√2×SEM minimal detectable change.
Prepare the measured movement, timing, load or preassigned score requested. Keep protocols, units, paired measurements and caller-selected thresholds consistent.
How to use Minimal Detectable Change and understand its results
- Prepare the measured movement, timing, load or preassigned score requested. Keep protocols, units, paired measurements and caller-selected thresholds consistent.
- Enter standardErrorMeasurement, confidenceZ, observedChange using the field table and calculation rules, then run the tool.
- Read mdc, exceedsMdc. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| standardErrorMeasurement | Standard error measurement | number | Required |
| confidenceZ | Confidence z | number | Required |
| observedChange | Observed change | number | Required |
Enter nonnegative SEM/change and positive critical z value. Return MDC and strict observed>MDC flag; equality is false.
MDC=z sqrt(2) SEM Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| mdc | Mdc | number |
| exceedsMdc | Exceeds mdc | boolean |
{
"input": {
"standardErrorMeasurement": 5,
"confidenceZ": 1.96,
"observedChange": 14
},
"output": {
"mdc": 13.85929291125633,
"exceedsMdc": true
}
}Limitations and assumptions
Confidence level, SEM estimate, independence and clinical importance are not established.
Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors. A successfully returned false flag is an evaluated outcome; its meaning is explained above.
Alternative or Complementary methods
Use Limb Symmetry Index: Calculate limb symmetry index from the supplied measurements. For a complementary task, use Cross Education Gain: Measure observed change in the untrained limb; does not establish a causal mechanism.
References
-
Minimal Detectable Change — tool.io
Similar or alternative tools
- Limb Symmetry Index
Calculate limb symmetry index from the supplied measurements.
- Cross Education Gain
Measure observed change in the untrained limb; does not establish a causal mechanism.