Reliability and Validity of the ActivForce Digital Dynamometer in Assessing Shoulder Muscle Force across Different User Experience Levels.
Christos Karagiannopoulos, Sean Griech, Brian Leggin
PMID 35693865WHAT IT FOUND
The ActivForce dynamometer is a reliable, affordable alternative to the standard microFET2 for measuring shoulder strength.
It performed consistently across experienced and novice testers, and patients found it more comfortable.
Key findings
01The ActivForce showed high intra- and inter-tester reliability for shoulder strength, comparable to the established microFET2, regardless of whether the tester was an expert or a novice.
02ActivForce readings correlated strongly with the microFET2 across external rotation, internal rotation, and forward elevation.
03Participants preferred the ActivForce over the microFET2 due to comfort during testing.
STILL TO COME
How it was doneWhat they foundWhat it means for PTsWhat it means for OTs
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
The study included only healthy adults, so results may not generalize to patients with shoulder pain or pathology. The sample size was small (29 participants) and recruited from a single university community. The ActivForce showed slightly higher measurement error (SEM) and minimal detectable change (MDC) compared to the microFET2, though this difference was not statistically tested. Testing was performed in a single session, which may not reflect real-world variability in patient effort or fatigue over multiple visits.
Declared interests
The authors declare no conflicts of interest. The study was approved by the DeSales University Institutional Review Board. No funding source is explicitly mentioned in the provided text.
The easy way to misread this
Do not assume the ActivForce is identical to the microFET2 in clinical precision. While reliable, it has a wider minimal detectable change (up to 8 lbs vs 6 lbs for the microFET2), meaning small fluctuations in strength scores may be measurement error rather than true clinical change.