Reported problems with accelerometer hardware and software in health research
| Hardware problems | Software problems | ||
| Derived categories | Findings | Derived categories | Findings |
| Battery problems | Battery problems were quite frequently reported. Battery life shortens over time and during cold weather periods, resulting in problems of data collection and data loss. | Lack of user-friendliness | Some users felt that often too many steps were necessary to process the data. Packages running in the R software environment (GGIR, accelerometry) were repeatedly reported as being too complicated to use. |
| Compliance issues | Another frequent problem. Compliance is reported to differ by placement, and consequently by device with best compliance in wrist-worn devices. Also, skin irritation has been reported. Children are especially prone to non-wearing uncomfortable devices, and to loss of devices. Moreover, children in a classroom setting will swap devices if not labelled. | Limited possibilities of software | Only a limited number of settings is available with shelf software. |
| Data loss | Data loss due to technical failure was reported frequently, without giving specific causes. In some cases, the manufacturer was able to rescue the data. | Software bugs | Software bugs were reported in varying detail. No general finding. |
| Mechanical problems | The accelerometer casings, the wrist straps, and other mechanical components were frequently reported to break. | High computational burden | High time complexity was repeatedly reported to be a problem with the Actilife software. |
| Electronic problems | There were some reports on faulty internal clocks, memory and Bluetooth issues. | Black box character of software | Data processing of software is not well documented, as a result the software appears non reliable to the user. This also poses a problem for scientific reporting as exact procedures are not known. |
| Sensor problems | Faulty signals, filtering or calibration issues were reported infrequently. | ||
| Lacking waterproofness | Lack of waterproofness is a problem, especially when active swimmers are in the sample. Some reported that they would manually add the activities to the derived parameters, which is cumbersome. | ||
| Other | Lack of comparability between devices, bankruptcy of one device manufacturer. General doubts on validity of the devices. | ||