Physical activity has significant positive effects on health, and accelerometers such as the Fitbit Inspire 3 can be used to track daily physical activity, A team of researchers conducted a study to evaluate the validity of the Fitbit Inspire 3 for assessing free-living daily steps in adults with transtibial amputations.
The study included 79 participants who completed a general health survey and were provided with a Fitbit Inspire 3 and an activPAL 3 accelerometer to wear concurrently for seven days in their home environment. Relationships between the activPAL and Fitbit Inspire 3 were examined using Pearson’s Correlation. Paired samples t tests, mean difference, mean absolute difference, and equivalence testing were used to compare daily step counts between the devices.
Average step counts were 5,768 ± 3,750 for the Fitbit Inspire 3 and 4,674 ± 3,081 for the activPAL. A high correlation but significant mean difference was found between the activPAL 3 and Fitbit Inspire 3. The mean absolute difference between the devices was 1,347 ± 1,184 steps.
On average, the Fitbit Inspire 3 counted 1,094 ± 1,423 more daily steps than the activPAL 3.
Because the Fitbit Inspire 3 counted more steps than the activPAL, and due to the significant mean differences and the large mean absolute difference between the devices, the activPAL 3 and Fitbit Inspire 3 are not interchangeable for estimating physical activity in individuals with transtibial amputations, the study concluded. However, due to the high correlation, the devices will produce similar classification rankings based on step counts.
The open-access study, “Comparison of daily step count between the Fitbit Inspire 3 and the activPAL 3 in adults with transtibial amputation,” was published in Frontiers in Rehabilitation Sciences.
